Codeposition of Polydopamine and Zwitterionic Polymer on

Subscriber access provided by University of South Dakota

Interface Components: Nanoparticles, Colloids, Emulsions, Surfactants, Proteins, Polymers

Co-deposition of Polydopamine and Zwitterionic Polymer on Membrane Surface with Enhanced Stability and Anti-biofouling Property Liangsong Yao, Chao He, Shengqiu Chen, Weifeng Zhao, Yi Xie, Shudong Sun, Shengqiang Nie, and Changsheng Zhao Langmuir, Just Accepted Manuscript • DOI: 10.1021/acs.langmuir.8b01621 • Publication Date (Web): 30 Jul 2018 Downloaded from http://pubs.acs.org on August 6, 2018

Just Accepted “Just Accepted” manuscripts have been peer-reviewed and accepted for publication. They are posted online prior to technical editing, formatting for publication and author proofing. The American Chemical Society provides “Just Accepted” as a service to the research community to expedite the dissemination of scientific material as soon as possible after acceptance. “Just Accepted” manuscripts appear in full in PDF format accompanied by an HTML abstract. “Just Accepted” manuscripts have been fully peer reviewed, but should not be considered the official version of record. They are citable by the Digital Object Identifier (DOI®). “Just Accepted” is an optional service offered to authors. Therefore, the “Just Accepted” Web site may not include all articles that will be published in the journal. After a manuscript is technically edited and formatted, it will be removed from the “Just Accepted” Web site and published as an ASAP article. Note that technical editing may introduce minor changes to the manuscript text and/or graphics which could affect content, and all legal disclaimers and ethical guidelines that apply to the journal pertain. ACS cannot be held responsible for errors or consequences arising from the use of information contained in these “Just Accepted” manuscripts.

is published by the American Chemical Society. 1155 Sixteenth Street N.W., Washington, DC 20036 Published by American Chemical Society. Copyright © American Chemical Society. However, no copyright claim is made to original U.S. Government works, or works produced by employees of any Commonwealth realm Crown government in the course of their duties.

Page 1 of 41 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Langmuir

1

Co-deposition of Polydopamine and Zwitterionic Polymer on

2

Membrane Surface with Enhanced Stability and Anti-biofouling

3

Property

4

Liangsong Yaoa, Chao Hea, Shengqiu Chena, Weifeng Zhaoa, Yi Xiea*, Shudong Suna,

5

Shengqiang Nieb, and Changsheng Zhaoa**

6 7

a

8

Materials Engineering, Sichuan University, Chengdu 610065, China

9

b

College of Polymer Science and Engineering, State Key Laboratory of Polymer

College of Chemistry and Materials Engineering, Guiyang University, Guiyang

10

550000, China

11

*Corresponding author.

12

E-mail address: [email protected] (*) or [email protected] (**)

13

Tel.: +86-28-85400453; Fax: +86-28-85405402.

14

ACS Paragon Plus Environment

Langmuir 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

1

Page 2 of 41

Abstract

2

Although abundant works have been developed in mussel-inspired antifouling

3

coatings, most of them suffer from poor chemical stability especially in strongly

4

alkaline environment. Herein, we report a robust one-step mussel-inspired method to

5

construct a highly chemical stable and excellent anti-biofouling membrane surface

6

coating, whereby a high-efficient co-deposition of polydopamine (PDA) with

7

zwitterionic polymer. In the study, PDA and polyethyleneimine quaternized derivative

8

(PEI-S) are co-deposited on the surface of polyethersulfone (PES) ultrafiltration

9

membrane in water at room temperature. In contrast to individual PDA coating, the

10

obtained PDA/PEI-S coating exhibits excellent chemical stability even in a strongly

11

alkaline environment owing to the cross-linking and unexpected cation-π interaction

12

between the PEI-S and PDA. Thanks to the introduction of PEI-S, systematical

13

proteins adsorption tests and bacteria adhesion experiments demonstrated that the

14

surfaces could prevent bovine serum fibrinogen (BFG) and lysozyme (Lyz) adsorption,

15

and could reduce gram-positive bacteria S. aureus and gram-negative bacteria E. coli

16

adhesion. Benefiting from the versatile functionality of PDA, the proposed strategy is

17

not limited to PES membrane surface but also others such as poly (ethylene

18

terephthalate) sheets and commercial polypropylene microfiltration membranes.

19

Overall, this work enriches the exploration of remarkable coating with enhanced

20

stability

21

materials-independent approach to modify membrane surface.

and

excellent

antifouling

property

via


a

facile,

robust

and

Page 3 of 41 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Langmuir

1 2

Keywords: Polydopamine, Zwitterionic polymer, Co-deposition, Anti-biofouling,

3

Cation-π interaction; Stability

4


Langmuir 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

1

Page 4 of 41

1. Introduction

2

Bio-fouling is a pervasive theme for numerous applications ranging from

3

biosensors to biomedical implants and devices; and from sea water desalination to

4

purification system.1-3 Therefore, endowing materials surface with antifouling

5

efficacy is strongly demanded in practical applications.4, 5

6

A common strategy to modify materials surface with anti-biofouling is

7

introducing hydrophilic polymers, such as poly(ethylene glycol),6, 7 oligosaccharide

8

moieties8,

9

grafting,15-17

9

and zwitterionic polymer or peptides10-13 through surface-initiating,14 self-assembly,18

sol-gel,19

layer-by-layer

assembly

(LBL),20,

21

10

mussel-inspired chemistry22 and so on. Proverbially, since Lee and his colleagues

11

proposed the mussel-inspired surface chemistry,23 many researchers reported that

12

materials surface could be modified by just immersing a substrate in a dopamine

13

solution for a few hours. Park et al. built active polydopamine (PDA) coating on a

14

membrane surface for improving the hydrophilicity,24 while the introduction of the

15

catechol and amino groups on a membrane surface showed good reactivity for further

16

modification.25 Meanwhile, this strategy could be used in various categories of

17

substrates, such as metals, silica and polymeric materials, and provided the facile

18

strategy to fabricate anti-fouling membrane surface.23 For example, in the Stamm and

19

co-workers’ work, a facile and straightforward method was successfully used to

20

prepare ultra-low fouling membranes by molecular functionalization process under

21

clean environment, interesting active molecules with tertiary amine functionality were

22

grafted to the polydopamine coatings surface.17 Moreover, in the work of Caruso and


Page 5 of 41 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Langmuir

1

colleagues, a versatile approach for the design of substrate-independent low-fouling

2

surfaces via mussel-inspired immobilization of zwitterionic peptides was reported,

3

and this low-fouling surface could be applied under various circumstances.13

4

Recently,

Xu

and

co-workers

reported

a

facile

way

to

obtain

5

PDA/polyethyleneimine-decorated membrane via one-step co-deposition method at a

6

mild condition.26 The as-prepared membrane surface showed less aggregates and

7

more chemical stability in alkaline environment in contrast to pure PDA-decorated

8

membranes in their works. Following this strategy, a large number of works have been

9

reported; and this system has been successfully proved to be used on various kinds of such

as

polysulfone

(PSf),27

polyimide

(PI)28

10

membranes,

and

11

polytetrafluoroethylene (PTFE);29 as well as functional silica nanoparticles30 or

12

hollow fiber membranes.31 Moreover, this co-deposition strategy could even be

13

employed directly in catecholamine/polyzwitterions system, which had been reported

14

by Xu and his colleagues more recently;32 in this work, PDA/poly(sulfobetaine

15

methacrylate) (PSBMA) co-deposition coating was constructed for improving

16

antifouling property. However, the co-deposition process needed lots of time (several

17

hours) and the coating held low chemical stability and unsatisfied property of solvent

18

resistance due to the non-covalent interaction. For further accelerating the reaction,

19

CuSO4/H2O2 system was used in a recent report.33 However, low chemical stability

20

of the coating was still a potential problem to be solved.

21

In our previous study, an amino-riched zwitterionic polymer was synthesized and

22

employed to endow PES membrane surface with antifouling ability. Meanwhile, it


Langmuir 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

1

could be effectively cross-linked with catechol groups to enhance the stability of the

2

antifouling layer.34 Nevertheless, the process needed two steps to prepare the

3

antifouling membrane surface. Therefore, we anticipated to provide a facile one-step

4

mussel-inspired strategy for obtaining a chemical stable anti-biofouling surface with

5

the amino-riched zwitterionic polymer; and such a one-step co-deposition could

6

improve the stability of coating by strengthening the interaction between PDA and

7

zwitterionic polymer with covalently bond anchoring.35

8

The purpose of the study is to provide an easy and effective strategy to construct

9

excellent anti-biofouling coatings with high stability via the co-deposition of PDA and

10

an amino-riched zwitterionic polymer (quaternary ammonium derivatives of

11

hyperbranched polyethyleneimine). The hydrophilicity and chemical stability of the

12

as-prepared surfaces were investigated; and the anti-protein adsorption and

13

anti-bacterial adhesion ability were systematically evaluated. To investigate the

14

universality of our modification method, the co-deposition of dopamine with

15

zwitterionic polymer was also employed on poly (ethylene terephthalate) (PET) sheets

16

and commercial polypropylene (PP) microfiltration membranes.

17 18

2. Experimental

19

2.1. Materials

20

Polyethersulfone (PES, Ultrason E6020P) powders were supplied by BASF. 1,

21

3-propanesultone (99%, Aladdin), sodium dodecyl sulfate (SDS, 99%, Aladdin),

22

dopamine hydrochloride (DA, 98%, Best Reagent), lysozyme (Lyz, 90%, Best), and


Page 6 of 41

Page 7 of 41 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Langmuir

1

polyethyleneimine (PEI, M.W. 10000, 99%, Aladdin) were used as received. Other

2

chemical reagents such as sodium chloride, disodium hydrogen phosphate, sodium

3

hydroxide, hydrochloric acid, ethanol, acetone, phosphatic buffer solution (PBS), and

4

dimethyl sulfoxide (DMSO) were purchased from Kelong (China). Micro BCATM

5

protein assay reagent kits were obtained from PIERCE. Bovine serum fibrinogen

6

(BFG) was provided by Sigma Chemical Co. Deionized water (DW) was utilized in

7

the whole study.

8

2.2. Polymer preparation and characterization

9

According to our previous studies,34, 36 an amino-riched zwitterionic polymer

10

was synthesized via quaternization of polyethyleneimine (PEI). Briefly, PEI (5.0 g)

11

and 1, 3-propanesultone (15.5 g) were separately dissolved by DMSO; and then the

12

solution of 1, 3-propanesultone was dropwise added into the PEI solution. After the

13

reaction performed at 40 oC for 12 h, the solution was precipitated in acetone. Then,

14

the precipitates were dissolved and dialyzed with DW. The products were obtained via

15

lyophilized and named as PEI-S; the schematic representation of the PEI-S

16

preparation is provided in Scheme S1 of Supporting information (SI).

17

To verify the successfully synthesized of PEI-S, the 1H NMR spectra was

18

recorded by Bruker AVⅡ-400 MHz spectrometer, (Bruker Cp., Germany). And then,

19

the grafted ratio of the 1, 3-propanesultone for PEI-S was 20.6%, which was

20

calculated from 1H NMR spectra. The detailed calculation process is depicted in SI.

21

2.3. Fabrication of modified PES membrane

22

Home-made PES membranes were prepared by the phase inversion method


Langmuir 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

1

which was mentioned in our previous work.37 PES powders were dissolved in DMSO

2

(16 wt. %), and the PES solution was spread on a square glass by spin-coating. Then

3

the glass was immersed in deionized water to prepare pristine PES membrane. The

4

obtained membranes named as M-PES were in a homogeneous thickness of 50 µm ±

5

5 µm (controlled by spin-coating); and its molecule weight cut off (MWCO) is about

6

20000 as shown in Table S2.

7

The M-PES membranes were soaked into a freshly prepared solution, which was

8

prepared by DA and PEI-S with a volume ratio of 1:1 in phosphate buffered saline

9

(PBS, 10 mM, pH=8.5), and the concentration of each component was 2 mg mL-1.

10

The obtained membranes were named as M-PDA/PEI-S, and the detailed process is

11

shown in Scheme 1. Moreover, a comparison study of the M-PES immersing in the

12

respected DA and PDA/PEI solutions was carried out at same concentration as

13

PDA/PEI-S co-deposition system; and the obtained membranes were named as

14

M-PDA and M-PDA/PEI, respectively. The modified membranes were rinsed three

15

times with DW after each treatment.

16


Page 8 of 41

Page 9 of 41 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Langmuir

1

Scheme 1. Schematic illustration for the one-step mussel-inspired antifouling

2

modification PES membrane.

3 4

2.4. Characterization for the membranes

5

Attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectra were

6

performed on a Fourier-transform infrared spectrometer (Nicolet 560, America). The

7

surface morphologies of the membranes were observed using a scanning electron

8

microscopy (SEM) (JSM-7500F, JEOL, Japan). X-ray photoelectron spectroscopy

9

(XPS) spectra were performed from a spectrometer (XSAM800, Kratos Analytical,

10

UK) with Al Kα excitation radiation to confirm the coatings of membranes. Surpass

11

Electrokinetic Analyzer (Anton Paar GmbH, Graz, Austria) was used to analyze the

12

surface zeta potential values. The detailed procedures were described in SI.

13

The water contact angles (WCA) of the membranes were measured by a contact

14

angle goniometer (Thera T200, Biolin Scientific, Sweden) The hydrophilicity and

15

stability of the modified membranes were evaluated via water contact angle (WCA)

16

measurement using a contact angle goniometer Theta T200 (Biolin Scientific, Sweden)

17

loaded with video capture. The membranes (1×1 cm2) for each piece were attached on

18

a glass slide to be measured. At least three measurements were used to obtain a

19

reliable value, and the measurement error was ±3°.

20

2.5. Protein adsorption tests

21

BFG and Lyz were chosen as the typical proteins to evaluate the anti-protein

22

adsorption ability of the membranes and the static protein adsorption test was carried


Langmuir 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

1

out according to our previous work.38 Firstly, the membrane was immersed in PBS,

2

with predetermined protein concentration and incubation time at 37 oC; then rinsed

3

slightly with DW and PBS alternatively, and then placed in the as-prepared 2 wt. %

4

SDS and vibrated for 2h. Then, the protein contents in the SDS was confirmed by the

5

Micro BCATM Protein Assay Reagent Kit. Details are supplied in SI.

6

2.6. Antibacterial tests

7

The antibacterial adhesion abilities of the membranes were evaluated by the

8

time-dependent co-culture of the membranes (two pieces, 1×1 cm2 for each) and

9

bacteria suspensions of Escherichia coli (E. coli, gram negative) or Staphylococcus.

10

aureus (S. aureus, gram positive) (2 mL, 106 Colony-Forming Units (CFU) mL-1) at

11

37 oC. The attached bacteria on the membranes were observed by a fluorescence

12

microscope after the bacteria were stained by the Bac Light viability kit. The

13

experimental procedures are described in detail in SI.

14 15

3. Results and discussion

16

3.1. Surface morphology and chemical composition for the membranes

17

As shown in Fig. 1A, the membrane surface of M-PES was smooth, while large

18

amounts of particles were observed on the M-PDA. Intriguingly, the surfaces of the

19

M-PDA/PEI and M-PDA/PEI-S were smooth and no distinct aggregates were

20

observed. Because of the non-covalently bonding between PDA molecules such as

21

π-π stacking and hydrogen bond, the PDA would form aggregates and deposited on

22

the surface; while the covalently cross-linking via Schiff-base reaction and Michael

23

addition between PEI and PDA or PEI-S and PDA weakened those kinds of weak


Page 10 of 41

Page 11 of 41 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Langmuir

1

interaction (π-π stacking and hydrogen bond) on M-PDA/PEI and M-PDA/PEI-S,

2

which might reduce the aggregated of PDA. These aggregates seemed to hold the

3

detrimental influence on the roughness of the membrane surfaces, which also

4

suggested the surface morphologies of the M-PDA/PEI and M-PDA/PEI-S

5

significantly changed compared to that of the M-PDA.

6

To further prove the hypothesis above, the digital images of the residual solution

7

after co-deposition are shown in Fig. 1B; the color of the dopamine solution was

8

cloud gray, and some black depositions were observed at the bottom of the solution

9

after 10 h, which suggested the formation of PDA aggregates on M-PDA; and the

10

solution was turned different degrees of brown in the end. In contrast to the above

11

solution, the solutions of the co-deposition systems (PDA/PEI and PDA/PEI-S) were

12

extremely stable, and the solution colors of different systems did not change

13

apparently, which might prove that the covalently cross-linking between PDA and PEI

14

or PDA and PEI-S weakened those kinds of weak interaction.

15 16

Fig. 1. (A) SEM images for pristine PES membrane, M-PDA(a), M-PDA/PEI and

17

M-PDA/PEI-S(b), the scale bars are 1µm; the SEM images for M-PDA(a’) and

18

M-PDA/PEI-S(b’) are the enlarged views of M-PDA(a) and M-PDA/PEI-S(b),


Langmuir 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

1

respectively; the inserted images are the digital photos of the membrane surfaces; (B)

2

images for the color change of the co-deposition residual solutions for PDA, PDA/PEI

3

and PDA/PEI-S, respectively (named S-PDA, S-PDA/PEI and S-PDA/PEI-S,

4

respectively) before and after 10 h standing.

5

6

Fig. 2A shows the surface colors of the membranes. As shown, with the increase

7

of the co-deposition time ranging from 1 to 12 h, the color changed from white to

8

caramel even in brown, suggesting that the extent of the reaction was deeper and

9

deeper. Meanwhile, the extent of the reaction was monitored via the WCA

10

measurements at different co-deposition times. Fig. 2B shows that the membranes

11

exhibited lower and lower WCAs with the increase of the co-deposition time,

12

indicating that the reaction was gradually deepened. The sufficient reaction was

13

wanted in this experiment, so the membranes co-deposited for 12 h were chosen for

14

the following study.

15

For better explaining the process of the attachment between the PDA/PEI-S and

16

pure PES membrane surfaces, the schematic representation of the attachment process

17

of PDA/PEI-S on PES membrane is illustrated in Fig. 2C. As we all known, DA

18

molecules would be oxidized and polymerized under alkaline condition ;39, 40 and the

19

PDA molecules could strongly interact with materials surface. In this study, PDA

20

molecules were cross-linked with the PEI-S via Schiff-based reaction and/or Michael

21

addition in alkaline environment;41 thus, the PDA/PEI-S might be effectively and

22

stably anchored on the membrane surface.

23

As shown in Fig 2D, the chemical components of the membrane surfaces were

24

characterized by ATR-FTIR. The specific absorption peak at 1039 cm-1 was observed


Page 12 of 41

Page 13 of 41 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Langmuir

1

on the spectrum of M-PDA/PEI-S, which was attributed to the existence of the SO3-

2

groups of zwitterionic structure. However, on the spectra of the M-PES, M-PDA and

3

M-PDA/PEI, this characteristic peak was not observed. The results indicated the

4

successful decoration of the membrane with PDA/PEI-S.

5 6

Fig. 2. (A) Real-time surface color change of the M-PDA and the co-deposited

7

membranes; (B) static WCAs for the modified PES membranes after 0 h, 1 h, 2 h, 4 h,

8

8 h and 12 h co-deposition; (C) schematic representation for the process of the

9

attachment between the co-deposition system and PES membrane surface; and (D) the

10

ATR-FTIR spectra of the modified membranes by immersing in dopamine solution

11

and the three co-deposition systems for 12 h.

12 13

Subsequently, the chemical components of the membranes were further revealed

14

by XPS; and as shown in Fig. 3, the M-PES displayed the peaks of O 1s (531.6 eV),

15

C 1s (284.7 eV) and S 2p (167.6 eV). The peaks of N 1s were probed after the

16

decoration with PDA, PDA/PEI; and the peak of 401 eV on the high-resolution N 1s


Langmuir 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

1

spectra of the M-PDA/PEI and M-PDA/PEI-S suggested the formation of C=N

2

bonds.34, 37 Further, as for Fig. 3C and Fig. 3D, because of the consumption of C-NH2

3

in Schiff base reaction and Michael addition which was showed in Scheme S3, the

4

mass fraction of the C-NH2 in PEI or PEI-S is much smaller than C-N-C and the peak

5

of C-N is assigned to the C-NH2 and C-N-C. Moreover, an apparent emergence of

6

C-N+ for M-PDA/PEI-S was probed as shown in the inserted images of Fig. 3D. The

7

contents of different elements for whole surfaces are shown in Table 1. For further

8

demonstrating our analysis, O 1s spectra were provided in Fig. S2 in SI. Compared

9

with M-PES, the shift of the S=O peak for M-PDA/PEI-S was another evidence for

10

the successful modification.

11 12

Fig. 3. XPS spectra for the surface of (A) M-PES, (B) M-PDA, (C) M-PDA/PEI and

13

(D) M-PDA/PEI-S. The inserted images are the N 1s spectra of M-PDA, M-PDA/PEI

14

and M-PDA/PEI-S.

15

Table 1. Surface elemental (atom %) components determined by XPS analysis. Element (atom %)

Sample


Page 14 of 41

Page 15 of 41 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Langmuir

C

O

S

N

M-PES

76.1

19.0

4.9

—

M-PDA

71.8

19.6

2.8

5.8

M-PDA/PEI

69.4

16.8

2.5

11.3

M-PDA/PEI-S

76.4

15.3

3.2

5.1

1 2

The zeta potential measurement was employed to investigate the change of

3

surface charge; and the data are shown in Fig. 4A. Compared with the M-PES and

4

M-PDA, the zeta potential value of M-PDA/PEI was positive (about +77.6 mV), since

5

the PEI was a typical positive polyelectrolyte.42 In contrast, the PEI-S was a kind of

6

zwitterionic polymer, which was regarded as a neutral material; and the neutrality of

7

M-PDA/PEI-S was confirmed by zeta potential value of about -3.8 mV.

8

To further demonstrate the surface charge property, adsorption experiments on

9

the membranes were carried out with positive molecules of methylene blue43 and

10

negative molecules of amaranth red;44 and the results are shown in Fig. S3. Among

11

these membranes, the M-PDA showed the highest adsorption capacity for the positive

12

molecules；while the M-PDA/PEI displayed the highest negative molecule adsorption.

13

As expected, the M-PDA/PEI-S could efficiently resist positive and negative

14

molecules adsorption. The results also indicated that the electrically neutral surface

15

was successfully fabricated.

16 17

Fig. 4. (A) Zeta potential values for the modified membranes; (B) static WCAs


Langmuir 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

1

for the modified PES membranes after 12h co-deposition.

2 3

3.2. Surface hydrophilicity of the modified membranes

4

Hydrophilicity of the decorated membranes was tested by WCA measurement.

5

As shown in Fig. 4B, the WCA for the M-PES was about 78° while that for the

6

M-PDA was about 51°. After the co-deposition, the M-PDA/PEI held the WCA

7

approximately 37°, while the M-PDA/PEI-S showed the WCA of about 29°.

8

Obviously, the WCAs for the M-PDA/PEI and M-PDA/PEI-S decreased compared

9

with the M-PDA membrane. It was clear that the PEI and PEI-S played crucial roles

10

on the change of membrane hydrophilicity after the co-deposition treating. In addition,

11

the hydrophilicity of the M-PDA/PEI-S was further perfected compared with

12

M-PDA/PEI owing to the ionic polarization of zwitterionic structure which has also

13

been reported in previous researches.45-47 Meanwhile, the water fluxes for the

14

membranes were evaluated and the data were shown in Table S1. M-PES held the

15

flux of 29.26 mL/m2·h·mmHg, and after modification, the fluxes of membrane

16

decreased to 12.85 mL/m2·h·mmHg of M-PDA, 8.14 mL/m2·h·mmHg of M-PDA/PEI

17

and 7.57 mL/m2·h·mmHg of M-PDA/PEI-S. Obviously, with the increase of the

18

thickness of the membranes, the perm-selectivity decreased as shown in Fig. S8. Thus,

19

the coating method would affect the water perm-selectivity of membrane.

20 21

3.3. The stability of the membrane surface

22

The chemical stability of the coatings on the membrane surfaces was crucial to

23

practical applications.48 As we all know, PDA coatings showed excellent stability in


Page 16 of 41

Page 17 of 41 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Langmuir

1

acidic, neutral and weak alkaline solutions, whereas the coatings would be

2

disintegrated in a strongly alkaline environment.49,

3

M-PDA, M-PDA/PEI and M-PDA/PEI-S after immersing in acidic and alkaline

4

environments with agitation 200 rpm were measured to evaluate those chemical

5

stabilities; and the results were shown in Fig. 5.

50

Herein, the WCAs of the

6

Compared with the original membranes in neutral environment, the WCAs of

7

the M-PDA, M-PDA/PEI and M-PDA/PEI-S presented very close WCAs about 52°,

8

37° and 29°, respectively, which indicated that all the membranes exhibited excellent

9

stability in an acidic solution with pH=2. However, the WCAs of the M-PDA suffered

10

from an increase in a weak alkaline solution with pH=12 and a significant increase in

11

a strongly alkaline solution with pH=14, while that of the M-PDA/PEI presented a

12

similar phenomenon in weak or strongly alkaline solution with pH=12 or pH=14.

13

Astoundingly, as shown in Fig. 5C, the WCAs of M-PDA/PEI-S were almost no

14

change whatever in neutral solution, acidic solution (pH=2), weak (pH=12) or

15

strongly (pH =14) alkaline solution. In a nutshell, the results indicated that the

16

M-PDA/PEI-S showed significant stability better than the M-PDA/PEI.

17


Langmuir 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

1

Fig. 5. WCAs of (A) M-PDA, (B) M-PDA/PEI and (C) M-PDA/PEI-S rinsed by

2

solutions with different pH values for 12h. The inserted images are the digital photos

3

of membranes after rinsing.

4 5

In addition, the chemical compositions of the membranes after 12h rinsing in an

6

alkaline solution (pH=14) were analyzed by XPS, and the results were showed in Fig.

7

6A. The peak of N 1s was observed apparently weak for M-PDA after rinsing which

8

proved the disappearance of PDA coating. Meanwhile, the alkaline solutions after

9

rinsing with the membranes for 12 h were recorded by a digital camera (Fig. S4), and

10

measured by the ultraviolet-visible spectra at 365 nm which caused by the Schiff base

11

bonds; and the results (as shown in Fig. 6B) confirmed the good chemical stability of

12

M-PDA/PEI-S.

13

Furthermore, for exploring the stability of the coating of M-PDA/PEI-S, the

14

membranes were immersed in 10 wt. % NaCl solution 12 h with agitation to study the

15

stability. As shown in Fig. S7, all the water contact angles of M-PDA, M-PDA/PEI

16

and M-PDA/PEI-S after rinsing in NaCl solution showed no significant change

17

compared to the ones before rinsing, indicating the coatings had good stability in

18

NaCl solution with high concentration (10 wt. %). Moreover, the experiment under

19

ultra-sonication in deionized water was performed; and the digital photos of the

20

membranes after the tests carrying out for 3 min and 5 min are shown in Fig. S6. As

21

shown in the figure, although the membranes were destroyed under the

22

ultra-sonication, it could be clearly observed that the coating of the M-PDA/PEI-S

23

showed good stability. Compared to M-PDA-PEI-S, the coatings destruction occurred

24

on some areas of M-PDA and M-PDA-PEI. For the M-PDA-PEI-S, no obvious

25

change was observed for the coating even after 5 min ultra-sonicaiton.


Page 18 of 41

Page 19 of 41 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Langmuir

1 2

Fig. 6. (A) XPS spectra for the membranes surface and (B) ultraviolet-visible spectra

3

for the alkaline solution (pH=14) after 12h rinsing the membranes (M-PDA,

4

M-PDA/PEI and M-PDA/PEI-S).

5

To prove the significant stability of the M-PDA/PEI-S, the interaction between

6

PDA and PEI or PEI-S was analyzed. Except for the cross-linking between the PDA

7

and PEI-S, which has been reported by Xu et al;26, 30 this remarkable stability in the

8

extremely alkaline environment could be ascribed to the cation-π interaction which

9

was deemed to widely present between electron-rich π system adjacent cations or

10

some polyelectrolytes containing positive charges to a large extent.51 In this

11

co-deposition system, PEI is a positively charged polyelectrolyte; while the PEI-S

12

served as a typical zwitterionic polymer which contained a large number of

13

quaternary ammonium ions, and the large amount of aromatic rings in PDA met the

14

request conditions of cation-π interaction.35,

15

binding affinity between the –NR4+ (R for alkyl chain) and aromatic rings, the

16

M-PDA/PEI-S showed better stability than M-PDA/PEI in our research.54 Also, the

17

possible existed interactions under aqueous condition are shown in Fig. 7, which

18

illustrates the cation-π interactions for the M-PDA/PEI and M-PDA/PEI-S.

52, 53

Moreover, due to the stronger


Langmuir 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

1

Nevertheless, the cation-π interaction was still a weak interaction compared to the

2

covalently bonding.33 To further confirm the cation-π interactions, another kind of

3

quaternarization derivate of PEI (PEI-Q), was synthesized (as shown in the Scheme

4

S2 in SI). Similarly, PEI-Q was co-deposited with PDA on PES membrane, and the

5

obtained membrane named as M-PDA/PEI-Q. Under the condition of pH=14, the

6

M-PDA/PEI-Q also showed remarkable stability, the data are shown in Fig. S5.54

7

These interactions could result in outstanding stable coating of M-PDA/PEI-S.

8

Overall, the above results further confirmed that the M-PDA/PEI-S presented

9

outstanding chemical stability in acidic, neutral, weak alkaline solutions and even in a

10

strongly alkaline environment which caused by covalently bonding and cation-π

11

interaction to a large extent.

12 13

Fig. 7. Schematic representation of interactions on substrate surface with PDA, PEI

14

and PEI-S, respectively.

15 16

3.4. Anti-biofouling properties for the membranes

17

3.4.1 Protein adsorption on the membranes surfaces


Page 20 of 41

Page 21 of 41 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Langmuir

1

Protein adsorption were usually employed to evaluate the anti-biofouling ability

2

of membranes. Herein, BFG (negatively charged) and Lyz (positively charged) were

3

chosen to be the protein models. As shown in Fig. 8, the M-PDA showed the highest

4

adsorption amounts for both Lyz and BFG which might be caused by the surface

5

roughness.2 The M-PDA/PEI showed low adsorption amount towards Lyz whereas

6

the adsorption amount towards BFG was nearly no change compared with that of the

7

M-PDA. Because PEI was a typical positively polyelectrolyte42, thus tended to adsorb

8

the negatively charged protein (BFG in this test) and repulse the positively charged

9

protein (Lyz in this test). Therefore, there were huge difference between the BFG and

10

Lyz adsorbed amounts of M-PDA/PEI. Furthermore, the M-PDA/PEI-S owned very

11

low adsorption amounts toward both Lyz and BFG, indicating that the M-PDA/PEI-S

12

exhibited more superior anti-biofouling property than pristine PES, M-PDA and

13

M-PDA/PEI. In this work, owning to zwitterionic structure, PEI-S played a crucial

14

role

15

sulphobetaine-polymer was reported before.55 As for a zwitterionic polymer, the

16

positive and negative charged units help to bind water molecules via electrostatic

17

force.56-58 In the presence of ions and water molecules, the water molecules on the

18

surface could form a stable solid hydration layer; and the stable solid hydration layer

19

exhibited a strong repulsion against proteins near the zwitterionic polymer modified

20

surface, which hindered protein adsorption.

in

anti-biofouling

property,

and

the

hydration


mechanism

of

Langmuir 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

1 2

Fig. 8. BFG and Lyz adsorption amounts onto the membranes.

3 4

3.4.2 Bacteria adhesion on the membranes surfaces

5

Bacteria attachment on membranes surface can rapidly proliferate, aggregate and

6

finally induce the formation of biofilm, which is tough to remove by physical or

7

chemical cleaning methods, and hinder the use of membranes.36 In this study, the

8

anti-bacterial activity of the membranes were qualitatively evaluated, and the results

9

are shown in Fig. 9. Compared to M-PES, the M-PDA showed high activity for

10

bacteria adherence; while the adhered quantities of E. coli and S. aureus (live and

11

dead) for the M-PDA/PEI-S were inappreciable. These results suggested that the

12

M-PDA/PEI-S owned distinguished and durable anti-bacterial activity against both E.

13

coli and S. aureus.


Page 22 of 41

Page 23 of 41 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Langmuir

1 2

Fig. 9. Representative fluorescence microscopy images showing E. coli and S. aureus

3

attachment to membranes (green staining represents live bacteria, and red staining

4

represents dead bacteria).

5 6

3.5. Universality of the modification method

7

To investigate the universality of our modification method, the anti-biofouling

8

coatings were further employed on other materials through the co-deposition method;

9

and poly (ethylene terephthalate) (PET) sheet and commercial polypropylene (PP)

10

microfiltration membrane were chosen in this study. And then the static WCAs of the

11

sheet and the membrane were measured to evaluate the hydrophilicity. As shown in

12

Fig. 10A, in contrast to pristine PET sheet and commercial PP microfiltration

13

membrane, the modified PET sheet and PP membrane both presented significantly

14

lower WCAs, which directly proved that this co-deposition system could be also


Langmuir 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 24 of 41

1

efficiently established on the surfaces of PET sheets and PP microfiltration

2

membranes.

3

Briefly sum up, a universal and stable anti-biofouling coating was obtained by

4

co-deposition of PDA with zwitterionic polymer, and the schematic illustration of the

5

anti-biofouling membrane surface was presented in Fig. 10B.

6 7

Fig. 10. (A) Static WCAs for modified PET and commercial PP microfiltration

8

membrane respectively and (B) schematic illustration of anti-biofouling membrane

9

surface.

10 11

4. Conclusion

12

In this study, we proposed a facile, robust and universal approach to construct a

13

significantly stable anti-biofouling coating on materials surface via one-step

14

co-deposition of PDA and zwitterionic polymer (PEI-S). The introduction of PEI-S

15

could effectively improve the antifouling ability of the PES membranes. Meanwhile,

16

the

17

(M-PDA/PEI-S) was significantly improved compared with PDA-decorated

18

membrane (M-PDA) surface due to the covalently cross-linking. Moreover, owing to

chemical stability of the

zwitterionic polymer co-deposited


coatings

Page 25 of 41 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Langmuir

1

the cation-π interaction, the M-PDA/PEI-S showed an excellent stability in extreme

2

alkaline condition. Furthermore, our strategy could also be successfully employed on

3

other materials, such as PET sheet and commercial PP microfiltration membrane.

4

Thus, the strategy proposed a fresh route to construct functional surface meeting with

5

the antifouling demand for diverse materials.

6 7

Acknowledgements

8

This work was financially sponsored by the National Natural Science Foundation

9

of China (Nos. 51503125, 51673125 and 51603048), the State Key Research

10

Development Programme of China (2016YFC1103000 and 2016YFC1103001), the

11

Program for Changjiang Scholars and Innovative Research Team in University

12

(IRT_15R48),

13

[2015]2008) and the Youth Science and Technology Innovation Team of Sichuan

14

Province (Grant No. 2015TD0001). We should also thank our laboratory members for

15

their generous help.

16

References

17 18 19 20 21 22 23 24 25 26 27 28

1.Banerjee; Pangule, R. C.; Kane, R. S., Antifouling coatings: recent developments in the design of

the Science and Technology Foundation of Guizhou Province (No. J

surfaces that prevent fouling by proteins, bacteria, and marine organisms. Adv. Mater. 2011, 23, (6), 690-718. 2.Rana, D.; Matsuura, T., Surface modifications for antifouling membranes. Chem. Rev. 2010, 110, (4), 2448-2471. 3.Yi, Z.; Zhu, L. P.; Xu, Y. Y.; Zhao, Y. F.; Ma, X. T.; Zhu, B. K., Polysulfone-based amphiphilic polymer for hydrophilicity and fouling-resistant modification of polyethersulfone membranes. J. Membr. Sci. 2010, 365, (1), 25-33. 4.Stamatialis, D. F.; Papenburg, B. J.; Gironés, M.; Saiful, S.; Bettahalli, S. N. M.; Schmitmeier, S.; Wessling, M., Medical applications of membranes: Drug delivery, artificial organs and tissue engineering. J. Membr. Sci. 2008, 308, (1), 1-34. 5.Kwon, B.; Molek, J.; Zydney, A. L., Ultrafiltration of PEGylated proteins: Fouling and concentration


Langmuir 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44

polarization effects. J. Membr. Sci. 2008, 319, (1), 206-213. 6.Ma, H.; Hyun, J.; Stiller, P.; Chilkoti, A., "Non‐Fouling" oligo(ethylene glycol)‐ functionalized polymer brushes synthesized by surface‐initiated atom transfer radical polymerization. Adv. Mater. 2004, 16, (4), 338-341. 7.Schilp, S.; Kueller, A.; Rosenhahn, A.; Grunze, M.; Pettitt, M. E.; Callow, M. E.; Callow, J. A., Settlement and adhesion of algal cells to hexa(ethylene glycol)-containing self-assembled monolayers with systematically changed wetting properties. Biointerphases 2007, 2, (4), 143-150. 8.Holland, N. B.; Qiu, Y. X.; Ruegsegger, M.; Marchant, R. E., Biomimetic engineering of non-adhesive glycocalyx-like surfaces using oligosaccharide surfactant polymers. Nature 1998, 392, (6678), 799-801. 9.Zhu, J. M.; Marchant, R. E., Dendritic saccharide surfactant polymers as antifouling interface materials to reduce platelet adhesion. Biomacromolecules 2006, 7, (4), 1036-1041. 10.Hayward, J. A.; Chapman, D., Biomembrane surfaces as models for polymer design: the potential for haemocompatibility. Biomaterials 1984, 5, (3), 135-142. 11.Ishihara, K.; Aragaki, R.; Ueda, T.; Watenabe, A.; Nakabayashi, N., Reduced thrombogenicity of polymers having phospholipid polar groups. J. Biomed. Mater. Res. 1990, 24, (8), 1069-77. 12.Mi, Y. F.; Zhao, F. Y.; Guo, Y. S.; Weng, X. D.; Ye, C. C.; An, Q. F., Constructing zwitterionic surface of nanofiltration membrane for high flux and antifouling performance. J. Membr. Sci. 2017, 541, 29-38. 13.Cui, J. W.; Ju, Y.; Liang, K.; Ejima, H.; Lorcher, S.; Gause, K. T.; Richardson, J. J.; Caruso, F., Nanoscale engineering of low-fouling surfaces through polydopamine immobilisation of zwitterionic peptides. Soft Matter 2014, 10, (15), 2656-2663. 14.Krishnamoorthy, M.; Hakobyan, S.; Ramstedt, M.; Gautrot, J. E., Surface-initiated polymer brushes in the biomedical field: applications in membrane science, biosensing, cell culture, regenerative medicine and antibacterial coatings. Chem. Rev. 2014, 114, (21), 10976-11026. 15.Yang, Y. F.; Li, Y.; Li, Q. L.; Wan, L. S.; Xu, Z. K., Surface hydrophilization of microporous polypropylene membrane by grafting zwitterionic polymer for anti-biofouling. J. Membr. Sci. 2010, 362, (1), 255-264. 16.Wei, X.; Wang, Z.; Chen, J.; Wang, J.; Wang, S., A novel method of surface modification on thin-film-composite reverse osmosis membrane by grafting hydantoin derivative. J. Membr. Sci. 2010, 346, (1), 152-162. 17.Tripathi, B. P.; Das, P.; Simon, F.; Stamm, M., Ultralow fouling membranes by surface modification with functional polydopamine. Eur. Polym. J. 2018, 99, 80-89. 18.Shen, L.; Cui, X.; Yu, G.; Li, F.; Li, L.; Feng, S.; Lin, H.; Chen, J., Thermodynamic assessment of adsorptive fouling with the membranes modified via layer-by-layer self-assembly technique. J. Colloid Interface Sci. 2017, 494, 194-203. 19.Detty, M. R.; Ciriminna, R.; Bright, F. V.; Pagliaro, M., Environmentally benign sol–gel antifouling and foul-releasing coatings. Acc. Chem. Res. 2014, 47, (2), 678-687. 20.Xu, L.; Pranantyo, D.; Liu, J.; Neoh, K. G.; Kang, E. T.; Ng, Y.; Laymingteo, S.; Fu, G., Layer-by-layer deposition of antifouling coatings on stainless steel via catechol-amine reaction. Rsc Adv. 2014, 4, (61), 32335-32344. 21.Chen, D.; Wu, M.; Li, B.; Ren, K.; Cheng, Z.; Ji, J.; Li, Y.; Sun, J., Layer-by-layer-assembled healable antifouling films. Adv. Mater. 2015, 27, (39), 5882-5888. 22.Faure, E.; Falentin-Daudré, C.; Jérôme, C.; Lyskawa, J.; Fournier, D.; Woisel, P.; Detrembleur, C., Catechols as versatile platforms in polymer chemistry. Prog. Polym. Sci. 2013, 38, (1), 236-270. 23.Lee, H.; Dellatore, S. M.; Miller, W. M.; Messersmith, P. B., Mussel-inspired surface chemistry for


Page 26 of 41

Page 27 of 41 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Langmuir

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44

multifunctional coatings. Science 2007, 318, (5849), 426-430. 24.Ryou, M. H.; Lee, Y. M.; Park, J. K.; Choi, J. W., Mussel-inspired polydopamine-treated polyethylene separators for high-power li-ion batteries. Adv. Mater. 2011, 23, (27), 3066-3070. 25.Dreyer, D. R.; Miller, D. J.; Freeman, B. D.; Paul, D. R.; Bielawski, C. W., Elucidating the structure of poly(dopamine). Langmuir 2012, 28, (15), 6428-6435. 26.Yang, H. C.; Liao, K. J.; Huang, H.; Wu, Q. Y.; Wan, L. S.; Xu, Z. K., Mussel-inspired modification of a polymer membrane for ultra-high water permeability and oil-in-water emulsion separation. J. Mater. Chem. A 2014, 2, (26), 10225-10230. 27.Wang, L.; Fang, F.; Liu, Y.; Li, J.; Huang, X., Facile preparation of heparinized polysulfone membrane assisted by polyfopamine/polyethyleneimine co-deposition for simultaneous LDL selectivity and biocompatibility. Appl. Surf. Sci. 2016, 385, 308-317. 28.Xu, L.; Xu, J.; Shan, B.; Wang, X.; Gao, C., Novel thin-film composite membranes via manipulating the synergistic interaction of dopamine and m-phenylenediamine for highly efficient forward osmosis desalination. J. Mater. Chem. A 2017, 5, (17), 7920-7932. 29.Xue, S.; Li, C.; Li, J.; Zhu, H.; Guo, Y., A catechol-based biomimetic strategy combined with surface mineralization to enhance hydrophilicity and anti-fouling property of PTFE flat membrane. J. Membr. Sci. 2017, 524, 409-418. 30.Lv, Y.; Du, Y.; Qiu, W. Z.; Xu, Z. K., Nanocomposite membranes via the codeposition of polydopamine/polyethylenimine with silica nanoparticles for enhanced mechanical strength and high water permeability. ACS Appl. Mater. Interfaces 2017, 9, (3), 2966-2972. 31.Song, H.; Yu, H.; Zhu, L.; Xue, L.; Wu, D.; Chen, H., Durable hydrophilic surface modification for PTFE hollow fiber membranes. React. Funct. Polym. 2017, 114, 110-117. 32.Zhou, R.; Ren, P. F.; Yang, H. C.; Xu, Z. K., Fabrication of antifouling membrane surface by poly(sulfobetaine methacrylate)/polydopamine co-deposition. J. Membr. Sci. 2014, 466, 18-25. 33.Zhang,

C.;

Li,

H.

N.;

Du,

Y.;

Ma,

M.

Q.;

Xu,

Z.

K.,

CuSO4/H2O2-triggered

polydopamine/poly(sulfobetaine methacrylate) coatings for antifouling membrane surfaces. Langmuir 2017, 33, (5), 1210-1216. 34.Chen, S.; Xie, Y.; Xiao, T.; Zhao, W.; Li, J.; Zhao, C., Tannic acid-inspiration and post-crosslinking of zwitterionic polymer as a universal approach towards antifouling surface. Chem. Eng. J. 2018, 337, 122-132. 35.Dougherty, D. A., Cation-pi interactions in chemistry and biology: a new view of benzene, Phe, Tyr, and Trp. Science 1996, 271, (5246), 163-168. 36.Xie, Y.; Tang, C.; Wang, Z.; Xu, Y.; Zhao, W.; Sun, S.; Zhao, C., Co-deposition towards mussel-inspired antifouling and antibacterial membranes by using zwitterionic polymers and silver nanoparticles. J. Mater. Chem. B 2017, 5, (34), 7186-7193. 37.Xie, Y.; Chen, L.; Zhang, X.; Chen, S.; Zhang, M.; Zhao, W.; Sun, S.; Zhao, C., Integrating zwitterionic polymer and Ag nanoparticles on polymeric membrane surface to prepare antifouling and bactericidal surface via Schiff-based layer-by-layer assembly. J. Colloid Interface Sci. 2018, 510, 308-317. 38.Nie, C.; Ma, L.; Cheng, C.; Deng, J.; Zhao, C., Nanofibrous heparin and heparin-mimicking multilayers as highly effective endothelialization and antithrombogenic coatings. Biomacromolecules 2015, 16, (3), 992-1001. 39.Yang, H.-C.; Luo, J.; Lv, Y.; Shen, P.; Xu, Z.-K., Surface engineering of polymer membranes via mussel-inspired chemistry. J. Membr. Sci. 2015, 483, 42-59. 40.Ingole, P. G.; Choi, W.; Kim, K. H.; Park, C. H.; Choi, W. K.; Lee, H. K., Synthesis, characterization and


Langmuir 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44

surface modification of PES hollow fiber membrane support with polydopamine and thin film composite for energy generation. Chem. Eng. J. 2014, 243, 137-146. 41.Zhao, C. X.; Zuo, F.; Liao, Z. J.; Qin, Z. L.; Du, S. N.; Zhao, Z. G., Mussel-Inspired One-Pot Synthesis of a Fluorescent and Water-Soluble Polydopamine-Polyethyleneimine Copolymer. Macromol. Rapid Commun. 2015, 36, (10), 909-915. 42.Xu, Y. C.; Wang, Z. X.; Cheng, X. Q.; Xiao, Y. C.; Shao, L., Positively charged nanofiltration membranes via economically mussel-substance-simulated co-deposition for textile wastewater treatment. Chem. Eng. J. 2016, 303, 555-564. 43.Du, J. J.; Yuan, Y. P.; Sun, J. X.; Peng, F. M.; Jiang, X.; Qiu, L. G.; Xie, A. J.; Shen, Y. H.; Zhu, J. F., New photocatalysts based on MIL-53 metal-organic frameworks for the decolorization of methylene blue dye. J. Hazard. Mater. 2011, 190, (1-3), 945-951. 44.Sasaki, Y. F.; Kawaguchi, S.; Kamaya, A.; Ohshita, M.; Kabasawa, K.; Iwama, K.; Taniguchi, K.; Tsuda, S., The comet assay with 8 mouse organs: results with 39 currently used food additives. Mutat. Res.-Genet. Toxicol. Environ. Mutag. 2002, 519, (1–2), 103-119. 45.Goddard, J. M.; Hotchkiss, J. H., Polymer surface modification for the attachment of bioactive compounds. Prog. Polym. Sci. 2007, 32, (7), 698-725. 46.Montalvo, G.; Khan, A., Self-assembly of mixed ionic and zwitterionic amphiphiles: Associative and dissociative interactions between lamellar phases. Langmuir 2002, 18, (22), 8330-8339. 47.Zeng, Z. P.; Yeh, L. H.; Zhang, M. K.; Qian, S. Z., Ion transport and selectivity in biomimetic nanopores with pH-tunable zwitterionic polyelectrolyte brushes. Nanoscale 2015, 7, (40), 17020-17029. 48.Zou, W.; Qin, H.; Shi, W.; Sun, S.; Zhao, C., Surface modification of poly(ether sulfone) membrane with a synthesized negatively charged copolymer. Langmuir 2014, 30, (45), 13622-13630. 49.Wei, H.; Ren, J.; Han, B.; Xu, L.; Han, L.; Jia, L., Stability of polydopamine and poly(DOPA) melanin-like films on the surface of polymer membranes under strongly acidic and alkaline conditions. Colloids Surf. B. Biointerfaces 2013, 110, (10), 22-28. 50.Jiang, J.; Zhu, L.; Zhu, L.; Zhang, H.; Zhu, B.; Xu, Y., Antifouling and antimicrobial polymer membranes based on bioinspired polydopamine and strong hydrogen-bonded poly(N-vinyl pyrrolidone). Appl. Mater. Interfaces 2013, 5, (24), 12895-12904. 51.Dougherty, D. A., The cation−π interaction. Acc. Chem. Res. 2012, 46, (4), 885-893. 52.Mecozzi, S.; West, A. P.; Dougherty, D. A., Cation−π interactions in simple aromatics: electrostatics provide a predictive tool. J. Am. Chem. Soc. 1996, 118, (9), 2307-2308. 53.Gallivan, J. P.; Dougherty, A. D., A computational study of cation−π interactions vs salt bridges in aqueous media: implications for protein engineering. J. Am. Chem. Soc. 2000, 122, (5), 870-874. 54.Lu, Q.; Oh, D. X.; Lee, Y.; Jho, Y.; Hwang, D. S.; Zeng, H., Nanomechanics of cation–π interactions in aqueous solution. Angew. Chem. 2013, 52, (14), 3944-3948. 55.Shao, Q.; He, Y.; White, A. D.; Jiang, S., Difference in Hydration between Carboxybetaine and Sulfobetaine. J. Phys. Chem. B 2010, 114, (49), 16625-16631. 56.Yang, W.; Chen, S.; Cheng, G.; Vaisocherová, H.; Xue, H.; Li, W.; Zhang, J.; Jiang, S., Film thickness dependence of protein adsorption from blood serum and plasma onto poly(sulfobetaine)-grafted surfaces. Langmuir 2008, 24, (17), 9211-9214. 57.He, Y.; Hower, J.; Chen, S.; Bernards, M. T.; Chang, Y.; Jiang, S., Molecular simulation studies of protein interactions with zwitterionic phosphorylcholine self-assembled monolayers in the presence of water. Langmuir 2008, 24, (18), 10358-10364.


Page 28 of 41

Page 29 of 41 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Langmuir

1 2

58.Yang, W.; Xue, H.; Li, W.; Zhang, J.; Jiang, S., Pursuing "zero" protein adsorption of poly(carboxybetaine) from undiluted blood serum and plasma. Langmuir 2009, 25, (19), 11911-6.

3


Langmuir 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Graphic Abstract 69x47mm (300 x 300 DPI)


Page 30 of 41

Page 31 of 41 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Langmuir

Schematic illustration for the one-step mussel-inspired antifouling modification PES membrane. 55x32mm (300 x 300 DPI)


Langmuir 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

(A) SEM images for pristine PES membrane, M-PDA(a), M-PDA/PEI and M-PDA/PEI-S(b), the scale bars are 1µm; the SEM images for M-PDA(a’) and M-PDA/PEI-S(b’) are the enlarged views of M-PDA(a) and MPDA/PEI-S(b), respectively; the inserted images are the digital photos of the membrane surfaces; (B) images for the color change of the co-deposition residual solutions for PDA, PDA/PEI and PDA/PEI-S, respectively (named S-PDA, S-PDA/PEI and S-PDA/PEI-S, respectively) before and after 10 h standing. 54x27mm (300 x 300 DPI)


Page 32 of 41

Page 33 of 41 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Langmuir

(A) Real-time surface color change of the M-PDA and the co-deposited membranes; (B) static WCAs for the modified PES membranes after 0 h, 1 h, 2 h, 4 h, 8 h and 12 h co-deposition; (C) schematic representation for the process of the attachment between the co-deposition system and PES membrane surface; and (D) the ATR-FTIR spectra of the modified membranes by immersing in dopamine solution and the three codeposition systems for 12 h. 61x39mm (300 x 300 DPI)


Langmuir 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

XPS spectra for the surface of (A) M-PES, (B) M-PDA, (C) M-PDA/PEI and (D) M-PDA/PEI-S. The inserted images are the N 1s spectra of M-PDA, M-PDA/PEI and M-PDA/PEI-S. 70x57mm (300 x 300 DPI)


Page 34 of 41

Page 35 of 41 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Langmuir

(A) Zeta potential values for the modified membranes; (B) static WCAs for the modified PES membranes after 12h co-deposition. 36x13mm (300 x 300 DPI)


Langmuir 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

WCAs of (A) M-PDA, (B) M-PDA/PEI and (C) M-PDA/PEI-S rinsed by solutions with different pH values for 12h. The inserted images are the digital photos of membranes after rinsing. 55x30mm (300 x 300 DPI)


Page 36 of 41

Page 37 of 41 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Langmuir

(A) XPS spectra for the membranes surface and (B) ultraviolet-visible spectra for the alkaline solution (pH=14) after 12h rinsing the membranes (M-PDA, M-PDA/PEI and M-PDA/PEI-S). 51x21mm (300 x 300 DPI)


Langmuir 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Schematic representation of interactions on substrate surface with PDA, PEI and PEI-S, respectively. 63x39mm (300 x 300 DPI)


Page 38 of 41

Page 39 of 41 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Langmuir

BFG and Lyz adsorption amounts onto the membranes. 79x62mm (300 x 300 DPI)


Langmuir 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Representative fluorescence microscopy images showing E. coli and S. aureus attachment to membranes (green staining represents live bacteria, and red staining represents dead bacteria) 75x56mm (300 x 300 DPI)


Page 40 of 41

Page 41 of 41 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Langmuir

(A) Static WCAs for modified PET and commercial PP microfiltration membrane respectively and (B) schematic illustration of anti-biofouling membrane surface. 49x19mm (300 x 300 DPI)


Codeposition of Polydopamine and Zwitterionic Polymer on

Recommend Documents