Morphology Control of Mesoporous Silica Particles Using Bile Acids

Article pubs.acs.org/cm

Cite This: Chem. Mater. 2018, 30, 4168−4175

Morphology Control of Mesoporous Silica Particles Using Bile Acids as Cosurfactants Leana Travaglini*,† and Luisa De Cola*,†,‡ †

CNRS, ISIS UMR 7006, Université de Strasbourg, 8 allée Gaspard Monge, 67000 Strasbourg, France Institut für Nanotechnologie (INT) - Building 640, Karlsruhe Institute of Technology (KIT), Campus Nord, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany

‡

Downloaded via KAOHSIUNG MEDICAL UNIV on July 1, 2018 at 18:36:43 (UTC). See https://pubs.acs.org/sharingguidelines for options on how to legitimately share published articles.

S Supporting Information *

ABSTRACT: Morphology control and tuning of nanomaterials are crucial to determine their properties and applications. Solutions based on different synthetic methodologies have been proposed, and in general they required variation of several parameters. Here, a new facile and cost-effective bottom-up strategy to control the morphology of mesoporous silica particles is presented. Specifically, catanionic templating systems composed of bile acids and CTAB enable the production of submicrometer MCM-41 particles of various shapes, high porosity, and remarkable features. The variation of a single component, the bile acid, leads to the preparation of particles with different morphologies. For instance, small (1 have shown improved cellular uptake in drug delivery.3,10,21,23 In addition, our platelets are very well-separated contrary to the hexagonal platelets reported to date, which are SBA-15 materials that are32,54−58 larger in size and show in most cases a high degree of intergrowth and/or twinned aggregation.11b,22 Such aggregation prevents their grafting onto surfaces and limits their use in several applications. In order to demonstrate that our hMPs can overcome such limitations a monolayer assembly of hMPs was obtained through their covalent linkage on glass plates (Figure 3), following a well-established procedure to prepare assembled monolayer of zeolite crystals.59−62

Figure 3. SEM images of the monolayer formed by hMPs-NH2 onto a glass slide. The image taken at higher magnification (b) clearly shows that the platelets are disposed in such a way that the pores are perpendicular to the glass surface.

Briefly, the monolayer was prepared by reacting glass plates, previously tethered with isocyanate groups, with aminofunctionalized hMPs (hMPs-NH2, see Supporting Information for details on synthesis and characterization). The monolayer is characterized by good coverage of the surface and coating homogeneity, and the particles lie parallel to the glass surface with no significant tilting or stacking, thus exposing the accessible pores and providing a large porous surface. XPS survey analysis confirmed the presence of hMPs-NH2 onto the glass plate surface (Figure S6). To prove the main role played by LCA in the preparation of the hMPs, a control experiment was performed, in identical experimental conditions but employing only CTAB as a template. In this case particles of spherical geometry (Figure 4a) with a mean diameter of 246 ± 29 nm (Figure S7) were observed. The particles show facets, reflecting the internal ordering well-visible in TEM micrographs (Figure 5a and Figure S8) and corresponding to a MCM-41 hexagonal mesostructure, as shown by SAXS analysis (Figure S9). The estimated pore diameter is 3.0 nm, confirmed by porosimetry measurements (Figure S10). The data clearly reveal that while mesostructure and porosity are retained, the introduction of LCA has a fundamental effect in determining the shape of the particles. In our synthesis the material phase separation occurs at an early stage, ca. 5 min after the addition of TEOS; thus, according to the CPSM 4170

DOI: 10.1021/acs.chemmater.8b01873 Chem. Mater. 2018, 30, 4168−4175

Article

Chemistry of Materials

Figure 4. SEM images of as-prepared particulate materials obtained using as templates (a) CTAB, (b) CTAB and salicylic acid, (c) CTAB and 2naphthoic acid, (d) CTAB and DCA, (e) CTAB and CA and performing the reaction at 50 °C using as templates (f) CTAB, (g) CTAB and LCA, (h) CTAB and DCA, and (i) CTAB and CA. In panels h and i the arrows indicate the hexagonal cross section. Scale bar = 500 nm.

fewer interactions and therefore to a less pronounced inhibition toward the adsorption of the growing silicates onto the micelles, which would be the weakest for C−. Such an effect would hence explain the gradual increase in thickness of the particles upon replacement of LCA with DCA and CA. The loss in long-range order suggested by the absence of (110) and (200) plane peaks in SAXS patterns may be instead explained by the fact that DCA and CA molecules could intercalate into the micelles as dimers to minimize the energy.49 The OH groups borne on the hydrophilic face of one molecule could therefore interact through H-bonding with the hydroxyl groups of the next molecule, preventing the presence of polar groups within the hydrophobic micelle core. Most likely, this intercalation would not occur always to the same extent, having the possible consequence of reducing the framework ordering. Similarly to what has been done for the hMPs, the presence of the DCA and CA within the templating micelles was proven by analyzing by LC-MS the solutions collected after extraction of the noncalcined particles. The spectra reported in Figures S18 and S19 showed the presence of both deoxycholate and cholate anions together with the hexadecyltrimethylammonium ion. The effect of temperature was also evaluated both in the presence and absence of the BAs by performing the reactions at 50 °C, where hydrolysis and polymerization of the silica source occur at an increased rate. Morphology, mesostructure, and porosity of the material obtained at 25 °C were retained (Figure 4f and Figures S20−S22) when only CTAB was used. Conversely, the presence of BAs led to twisted rod-like particles (Figures 4g−1). Those formed in the presence of LCA are characterized by length up to 1 μm and ca. 80 nm cross-section diameter (Figure 4g and Figure S23). TEM showed 2D chiral

the shape of the particles, but the hydrophobicity and bulkiness of the organic anion play a fundamental role in determining the particle morphology. To further elucidate the correlation between the effect on the morphology and the molecular structure of the cosurfactant, we replaced LCA by DCA and CA possessing an increasing hydrophilic character, bearing two and three OH groups, respectively. This not only allows for a good comparison with LCA in terms of size and shape but also tests the significant effect of the amphiphilicity to modulate the shape of the particles. Deoxycholate (DC−) had an effect similar to that of LC−, leading to hexagonal plate-like particles of comparable width (Figure 4d and Figure S12), but slightly larger height (ca. 200 nm). In the presence of cholate (C−) oblate particles were formed being the hexagonal profile less pronounced (Figure 4e). The width was comparable (423 ± 43 nm, Figure S14), while the height larger, ranging from 180 to 350 nm. In both cases TEM (Figure 5b,c and Figures S13 and S15) revealed pore channels parallel to the particle short dimension and the SAXS pattern showed a main peak at q = 1.84 and 1.90 nm−1, respectively. A smaller broad peak at higher q values is also visible, suggesting the presence of slightly smaller pores in the structure (Figure S16). This is supported by the broader pore width distributions calculated from N2 sorption (Figure S17) and the slightly smaller average pore diameters calculated as 2.8 and 2.7 nm for particles templated by DCA- and CA-containing mixtures, respectively. Both materials show high porosity since BET surface areas correspond to 1228 and 1509 m2/g and total pore volumes to 0.64 and 0.79 cm3/g. These results suggest that DC− and C− interact less with CTA+ micelles. The higher solubility in water would determine the intercalation of the molecules to a lesser extent, leading to 4171


Article


(Figure S33, BET 1130 m2/g, total pore volume 0.99 cm3/g). Again, proof of the presence of the BAs within the nonextracted particles was provided by LC-MS analysis (Figures S34−S36) on the solutions collected after extraction with MeOH, since the spectra clearly showed the presence of the lithocholate, deoxycholate, and cholate anions. The elongated twisted shape suggests that at 50 °C the presence of BAs favors the growth of the particles along the channel direction to produce rod-like particles with hexagonal cross section. This is most probably the result of the interplay of several factors. As already mentioned, it is known that the insertion of BA molecules into a CTAB micelle lowers its curvature, favoring the growth into elongated micelles.46 This effect depends on the extent to which the intercalation occurs, dictated by the solubility in water of the BA monomers. It means that this effect would be stronger in the order for LCA > DCA > CA. As stated above, at 25 °C elongated particles are not observed because the screening of positive charges due to electrostatic interactions likely delays the silicates adsorption and subsequent polymerization. The different behavior at 50 °C is most probably due to the concommitance of more favorable hydrophobic interactions and higher speed rate of silica condensation. In fact, hydrophobic interactions between amphiphilic molecules in water are generally stronger at higher temperature, causing the aggregates to compact and grow in size and length. The faster silica polymerization would instead counterbalance the delay in adsorption and condensation due to charge screening, further favoring the growth of elongated objects. The insertion of the chiral rigid curved steroidal moiety may contribute to induce strain in the system and impart the twist, which could also be induced by the tendency of the system to reduce the surface energy. Further, it is possible to notice that the more hydrophilic the BA, the shorter and wider are the resulting twisted rods, in accordance with the less tendency toward the BA insertion into the micelles. It follows that a higher number of inserted BA molecules would lead to longer rods and to a higher degree of twisting in order to minimize the lateral surface.Besides the elucidation of the role of BAs in the process, it is also worth noting that our templating system allows easy access to chiral mesoporous silica, and special attention has been recently paid to the synthesis of chiral mesoporous silica particles due to their potential as templates for metal nanowires with tunable properties or as supports in catalysis or chiral recognition. The first example of chiral mesoporous silica was reported by Che et al., who prepared chiral rods employing chiral anionic surfactants as to impart chirality to the particles.19 Notably, this work represents also the first example in which the morphology control is obtained through the introduction of cotemplates inducing variation of the silica-template interactions. Since then, various examples of chiral mesoporous silica prepared by using chiral or achiral structure directing agents,68−71 or simply upon addition of swelling agents to the system,1 in conditions that favored the growth of fibers that eventually twist into chiral structures in order to minimize the surface energy.72,73 However, our system certainly provides an alternative costeffective way to synthesize these types of materials.

Figure 5. TEM images of calcined particulate material obtained using as templates (a) CTAB, (b) CTAB and DCA, (c) CTAB and CA and performing the reaction at 50 °C using as templates (d) CTAB and LCA, (e) CTAB and DCA, and (f) CTAB and CA. In panels e and f the arrows indicate the fringes. Scale bars = 100 nm.

Figure 6. Schematic representation of the probable interactions between LC− and CTA+ micelles.

pores running along the rods and a twist pitch of ca. 40 nm can be estimated from the fringes (Figure 5d and Figure S24). As inferred from the SAXS pattern, 3.4 nm pores are arranged in p6mm symmetry (Figure S25). The pore width was confirmed by N2 adsorption (Figure S26), which also provided a BET surface area of 1319 m2/g and total pore volume of 0.92 cm3/g. Twisted rods prepared in the presence of DCA were considerably shorter and characterized by a larger cross-section diameter (Figure 4h and Figure S24) and a larger twist pitch of ca. 100 nm (Figure 5e and Figure S27). They showed a hexagonal cross section and 3.4 nm pores hexagonally ordered (Figures S28 and S30) running along the particles. BET surface area and pore volume were estimated as 1215 m2/g and 1.09 cm3/g. The use of CA led to further shorter and wider rod-like particles (Figure 4i and Figure S31) for which the twisting could be clearly appreciated by TEM (Figure 5f and Figure S32) but did not affect either mesostructure or pore properties

■

CONCLUSIONS In summary, we showed that using CTAB/BAs binary mixtures as templating agents it is possible to attain good control of MSPs overall shape, in alkaline aqueous conditions. For the first time the use of BAs in the synthesis of mesoporous silica is 4172


Article


(7) Tarn, D.; Ashley, C. E.; Xue, M.; Carnes, E. C.; Zink, J. I.; Brinker, C. J. Mesoporous Silica Nanoparticle Nanocarriers: Biofunctionality and Biocompatibility. Acc. Chem. Res. 2013, 46 (3), 792−801. (8) Croissant, J. G.; Fatieiev, Y.; Almalik, A.; Khashab, N. M. Mesoporous Silica and Organosilica Nanoparticles: Physical Chemistry, Biosafety, Delivery Strategies, and Biomedical Applications. Adv. Healthcare Mater. 2018, 7 (4), 1700831. (9) Du, X.; Li, X.; Xiong, L.; Zhang, X.; Kleitz, F.; Qiao, S. Z. Mesoporous silica nanoparticles with organo-bridged silsesquioxane framework as innovative platforms for bioimaging and therapeutic agent delivery. Biomaterials 2016, 91, 90−127. (10) Giglio, V.; Varela-Aramburu, S.; Travaglini, L.; Fiorini, F.; Seeberger, P. H.; Maggini, L.; De Cola, L. Reshaping Silica Particles: Mesoporous Nanodiscs for Bimodal Delivery and Improved Cellular Uptake. Chem. Eng. J. 2018, 340, 148−154. (11) Maggini, L.; Cabrera, I.; Ruiz-Carretero, A.; Prasetyanto, E. A.; Robinet, E.; De Cola, L. Breakable mesoporous silica nanoparticles for targeted drug delivery. Nanoscale 2016, 8 (13), 7240−7247. (12) Liu, J.; Detrembleur, C.; De Pauw-Gillet, M.-C.; Mornet, S.; Elst, L. V.; Laurent, S.; Jerome, C.; Duguet, E. Heat-triggered drug release systems based on mesoporous silica nanoparticles filled with a maghemite core and phase-change molecules as gatekeepers. J. Mater. Chem. B 2014, 2 (1), 59−70. (13) Croissant, J. G.; Fatieiev, Y.; Khashab, N. M. Degradability and Clearance of Silicon, Organosilica, Silsesquioxane, Silica Mixed Oxide, and Mesoporous Silica Nanoparticles. Adv. Mater. 2017, 29 (9), 1604634. (14) Croissant, J.; Cattoën, X.; Man, M. W. C.; Gallud, A.; Raehm, L.; Trens, P.; Maynadier, M.; Durand, J. O. Biodegradable EthyleneBis(Propyl)Disulfide-Based Periodic Mesoporous Organosilica Nanorods and Nanospheres for Efficient In-Vitro Drug Delivery. Adv. Mater. 2014, 26 (35), 6174−6180. (15) Croissant, J. G.; Fatieiev, Y.; Julfakyan, K.; Lu, J.; Emwas, A. H.; Anjum, D. H.; Omar, H.; Tamanoi, F.; Zink, J. I.; Khashab, N. M. Biodegradable Oxamide-Phenylene-Based Mesoporous Organosilica Nanoparticles with Unprecedented Drug Payloads for Delivery in Cells. Chem. - Eur. J. 2016, 22 (42), 14806−14811. (16) Villegas, M.; Garcia-Uriostegui, L.; Rodríguez, O.; IzquierdoBarba, I.; Salinas, A.; Toriz, G.; Vallet-Regí, M.; Delgado, E. LysineGrafted MCM-41 Silica as an Antibacterial Biomaterial. Bioengineering 2017, 4 (4), 80. (17) Martinez-Carmona, M.; Lozano, D.; Baeza, A.; Colilla, M.; Vallet-Regi, M. A novel visible light responsive nanosystem for cancer treatment. Nanoscale 2017, 9 (41), 15967−15973. (18) Boissière, C.; Kümmel, M.; Persin, M.; Larbot, A.; Prouzet, E. Spherical MSU-1 Mesoporous Silica Particles Tuned for HPLC. Adv. Funct. Mater. 2001, 11 (2), 129−135. (19) Che, S.; Liu, Z.; Ohsuna, T.; Sakamoto, K.; Terasaki, O.; Tatsumi, T. Synthesis and characterization of chiral mesoporous silica. Nature 2004, 429 (6989), 281−284. (20) Sujandi; Park, S.-E.; Han, D.-S.; Han, S.-C.; Jin, M.-J.; Ohsuna, T. Amino-functionalized SBA-15 type mesoporous silica having nanostructured hexagonal platelet morphology. Chem. Commun. 2006, No. 39, 4131−4133. (21) Huang, X.; Li, L.; Liu, T.; Hao, N.; Liu, H.; Chen, D.; Tang, F. The Shape Effect of Mesoporous Silica Nanoparticles on Biodistribution, Clearance, and Biocompatibility in Vivo. ACS Nano 2011, 5 (7), 5390−5399. (22) Blanco, E.; Shen, H.; Ferrari, M. Principles of nanoparticle design for overcoming biological barriers to drug delivery. Nat. Biotechnol. 2015, 33 (9), 941−951. (23) Trewyn, B. G.; Nieweg, J. A.; Zhao, Y.; Lin, V. S. Y. Biocompatible mesoporous silica nanoparticles with different morphologies for animal cell membrane penetration. Chem. Eng. J. 2008, 137 (1), 23−29. (24) Edler, K. J. Current Understanding of Formation Mechanisms in Surfactant-Templated Materials. Aust. J. Chem. 2005, 58 (9), 627−643.

reported and provides a simple method to control the morphology of the particles varying a single parameter. The specific interaction between the two surfactants is responsible for the described variation of shape, size, and aspect ratio. Specifically, the bulkiness and the amphiphilicity of the bile acids play a major role. The contribution of temperature was also evaluated, but yet the tuning of the structures depends on the bile acid employed. This method enabled us to obtain MCM-41 submicrometer MSPs of various shapes, with well-ordered pores, high porosity, and remarkable features. As we showed, small hexagonal platelets and twisted chiral rods with tunable aspect ratio were obtained with our method, and both are particularly promising in the design of functional materials. The first are ideal to be integrated onto surfaces, while the latter ones are attractive templates or supports for separations. This work certainly paves the way to a new cost-effective and efficient strategy for the morphology modulation of mesoporous silica particles.

■

ASSOCIATED CONTENT

S Supporting Information *

The Supporting Information is available free of charge on the ACS Publications website at DOI: 10.1021/acs.chemmater.8b01873. Experimental details, description of materials and instruments, and additional figures (PDF)

■

AUTHOR INFORMATION

Corresponding Authors

*E-mail: [email protected] (L.T.). *E-mail: [email protected] (L.D.C.). ORCID

Luisa De Cola: 0000-0002-2152-6517 Notes

The authors declare no competing financial interest.

■

ACKNOWLEDGMENTS This work was financially supported by the European Commission through the SACS Project (grant no. 310651). Prof. L. De Cola acknowledges AXA Research Fund for financial support. The authors thank Dr. S. Silvestrini for XPS measurement on the monolayer and Dr. P. Chen for XPS measurements on pristine and amino-functionalized platelets and nitrogen sorption measurements on hexagonal platelets and spherical particles.

■

REFERENCES

(1) Möller, K.; Bein, T. Talented Mesoporous Silica Nanoparticles. Chem. Mater. 2017, 29 (1), 371−388. (2) Li, Z.; Barnes, J. C.; Bosoy, A.; Stoddart, J. F.; Zink, J. I. Mesoporous silica nanoparticles in biomedical applications. Chem. Soc. Rev. 2012, 41 (7), 2590−2605. (3) Slowing, I. I.; Vivero-Escoto, J. L.; Trewyn, B. G.; Lin, V. S. Y. Mesoporous silica nanoparticles: structural design and applications. J. Mater. Chem. 2010, 20 (37), 7924−7937. (4) Huo, Q.; Margolese, D. I.; Stucky, G. D. Surfactant Control of Phases in the Synthesis of Mesoporous Silica-Based Materials. Chem. Mater. 1996, 8 (5), 1147−1160. (5) Wu, S.-H.; Mou, C.-Y.; Lin, H.-P. Synthesis of mesoporous silica nanoparticles. Chem. Soc. Rev. 2013, 42 (9), 3862−3875. (6) Wan, Y.; Zhao. On the Controllable Soft-Templating Approach to Mesoporous Silicates. Chem. Rev. 2007, 107 (7), 2821−2860. 4173


Article

Chemistry of Materials (25) Holmberg, K. Surfactant-templated nanomaterials synthesis. J. Colloid Interface Sci. 2004, 274 (2), 355−364. (26) Berggren, A.; Palmqvist, A. E. C.; Holmberg, K. Surfactanttemplated mesostructured materials from inorganic silica. Soft Matter 2005, 1 (3), 219−226. (27) Yu, C.; Fan, J.; Tian, B.; Zhao, D. Morphology Development of Mesoporous Materials: a Colloidal Phase Separation Mechanism. Chem. Mater. 2004, 16 (5), 889−898. (28) Chan, H. B. S.; Budd, P. M.; Naylor, T. d., Control of mesostructured silica particle morphology. J. Mater. Chem. 2001, 11 (3), 951−957. (29) Qu, Q.; Zhou, G.; Ding, Y.; Feng, S.; Gu, Z. Adjustment of the morphology of MCM-41 silica in basic solution. J. Non-Cryst. Solids 2014, 405, 104−115. (30) Zhao, D.; Sun, J.; Li, Q.; Stucky, G. D. Morphological Control of Highly Ordered Mesoporous Silica SBA-15. Chem. Mater. 2000, 12 (2), 275−279. (31) Linton, P.; Wennerstrom, H.; Alfredsson, V. Controlling particle morphology and size in the synthesis of mesoporous SBA-15 materials. Phys. Chem. Chem. Phys. 2010, 12 (15), 3852−3858. (32) Björk, E. M.; Söderlind, F.; Odén, M. Tuning the Shape of Mesoporous Silica Particles by Alterations in Parameter Space: From Rods to Platelets. Langmuir 2013, 29 (44), 13551−13561. (33) Naik, S. P.; Elangovan, S. P.; Okubo, T.; Sokolov, I. Morphology Control of Mesoporous Silica Particles. J. Phys. Chem. C 2007, 111 (30), 11168−11173. (34) Yang, H.; Vovk, G.; Coombs, N.; Sokolov, I.; Ozin, G. A. Synthesis of mesoporous silica spheres under quiescent aqueous acidic conditions. J. Mater. Chem. 1998, 8 (3), 743−750. (35) Han, L.; Zhou, Y.; He, T.; Song, G.; Wu, F.; Jiang, F.; Hu, J. One-pot morphology-controlled synthesis of various shaped mesoporous silica nanoparticles. J. Mater. Sci. 2013, 48 (17), 5718−5726. (36) Lin, H.-P.; Mou, C.-Y. Structural and Morphological Control of Cationic Surfactant-Templated Mesoporous Silica. Acc. Chem. Res. 2002, 35 (11), 927−935. (37) Galantini, L.; di Gregorio, M. C.; Gubitosi, M.; Travaglini, L.; Tato, J. V.; Jover, A.; Meijide, F.; Soto Tellini, V. H.; Pavel, N. V. Bile salts and derivatives: Rigid unconventional amphiphiles as dispersants, carriers and superstructure building blocks. Curr. Opin. Colloid Interface Sci. 2015, 20 (3), 170−182. (38) Madenci, D.; Egelhaaf, S. U. Self-assembly in aqueous bile salt solutions. Curr. Opin. Colloid Interface Sci. 2010, 15 (1−2), 109−115. (39) Bonincontro, A.; Briganti, G.; D’Archivio, A. A.; Galantini, L.; Giglio, E. Structural Study of the Micellar Aggregates of Sodium Taurodeoxycholate. J. Phys. Chem. B 1997, 101 (49), 10303−10309. (40) Bonincontro, A.; D’Archivi, A. A.; Galantini, L.; Giglio, E.; Punzo, F. On the Micellar Aggregates of Alkali Metal Salts of Deoxycholic Acid. J. Phys. Chem. B 1999, 103 (24), 4986−4991. (41) D’Archivio, A. A.; Galantini, L.; Gavuzzo, E.; Giglio, E.; Scaramuzza, L. Possible Models for the Micellar Aggregates of Glycocholate and Taurocholate Salts from Crystal Structures, QELS, and CD Measurements. Langmuir 1996, 12 (20), 4660−4667. (42) Huang, X.; Weiss, R. G. Rodlike silica and titania objects templated on extremely dilute aqueous dispersions of self-assembled sodium lithocholate nanotubes. J. Colloid Interface Sci. 2007, 313 (2), 711−716. (43) Qiao, Y.; Lin, Y.; Wang, Y.; Yang, Z.; Liu, J.; Zhou, J.; Yan, Y.; Huang, J. Metal-Driven Hierarchical Self-Assembled One-Dimensional Nanohelices. Nano Lett. 2009, 9 (12), 4500−4504. (44) Liang, W.; He, S.; Wang, Y.; Fang, J. Morphology and Shape Control of Porous Silica Nanostructures with Dual-Templating Approaches. J. Nanosci. Nanotechnol. 2014, 14 (6), 4424−4430. (45) Swanson-Vethamuthu, M.; Almgren, M.; Hansson, P.; Zhao, J. Surface Tension Studies of Cetyltrimethylammonium Bromide−Bile Salt Association. Langmuir 1996, 12 (9), 2186−2189. (46) Swanson-Vethamuthu, M.; Almgren, M.; Karlsson, G.; Bahadur, P. Effect of Sodium Chloride and Varied Alkyl Chain Length on Aqueous Cationic Surfactant−Bile Salt Systems. Cryo-TEM and Fluorescence Quenching Studies. Langmuir 1996, 12 (9), 2173−2185.

(47) Jana, P. K.; Moulik, S. P. Interaction of bile salts with hexadecyltrimethylammonium bromide and sodium dodecyl sulfate. J. Phys. Chem. 1991, 95 (23), 9525−9532. (48) La Mesa, C.; Khan, A.; Fontell, K.; Lindman, B. Phase diagrams and NMR studies of some ternary sodium deoxycholate-surfactantwater systems. J. Colloid Interface Sci. 1985, 103 (2), 373−391. (49) Vethamuthu, M. S.; Almgren, M.; Mukhtar, E.; Bahadur, P. Fluorescence quenching studies of the aggregation behavior of the mixed micelles of bile salts and cetyltrimethylammonium halides. Langmuir 1992, 8 (10), 2396−2404. (50) Liu, C.; Cui, J.; Song, A.; Hao, J. A bile acid-induced aggregation transition and rheological properties in its mixtures with alkyltrimethylammonium hydroxide. Soft Matter 2011, 7 (19), 8952−8960. (51) Chen, C.-Y.; Li, H.-X.; Davis, M. E. Studies on mesoporous materials: I. Synthesis and characterization of MCM-41. Microporous Mater. 1993, 2 (1), 17−26. (52) Cai, Q.; Luo, Z.-S.; Pang, W.-Q.; Fan, Y.-W.; Chen, X.-H.; Cui, F.-Z. Dilute Solution Routes to Various Controllable Morphologies of MCM-41 Silica with a Basic Medium. Chem. Mater. 2001, 13 (2), 258−263. (53) Lin, Y.-S.; Lu, C.-Y. D.; Hung, Y.; Mou, C.-Y. Uniform Mesoporous Silica Hexagon and Its Two-Dimensional Colloidal Crystal. ChemPhysChem 2009, 10 (15), 2628−2632. (54) Chen, S.-Y.; Tang, C.-Y.; Chuang, W.-T.; Lee, J.-J.; Tsai, Y.-L.; Chan, J. C. C.; Lin, C.-Y.; Liu, Y.-C.; Cheng, S. A Facile Route to Synthesizing Functionalized Mesoporous SBA-15 Materials with Platelet Morphology and Short Mesochannels. Chem. Mater. 2008, 20 (12), 3906−3916. (55) Cao, L.; Kruk, M. Facile method to synthesize platelet SBA-15 silica with highly ordered large mesopores. J. Colloid Interface Sci. 2011, 361 (2), 472−476. (56) Prasetyanto, E. A.; Ansari, M. B.; Min, B.-H.; Park, S.-E. Melamine tri-silsesquioxane bridged periodic mesoporous organosilica as an efficient metal-free catalyst for CO2 activation. Catal. Today 2010, 158 (3−4), 252−257. (57) Zhu, Y.; Li, H.; Xu, J.; Yuan, H.; Wang, J.; Li, X. Monodispersed mesoporous SBA-15 with novel morphologies: controllable synthesis and morphology dependence of humidity sensing. CrystEngComm 2011, 13 (2), 402−405. (58) Alfredsson, V.; Wennerström, H. The Dynamic Association Processes Leading from a Silica Precursor to a Mesoporous SBA-15 Material. Acc. Chem. Res. 2015, 48 (7), 1891−1900. (59) Yoon, K. B. Organization of Zeolite Microcrystals for Production of Functional Materials. Acc. Chem. Res. 2007, 40 (1), 29−40. (60) Zabala Ruiz, A.; Li, H.; Calzaferri, G. Organizing Supramolecular Functional Dye−Zeolite Crystals. Angew. Chem., Int. Ed. 2006, 45 (32), 5282−5287. (61) Greco, A.; Maggini, L.; De Cola, L.; De Marco, R.; Gentilucci, L. Diagnostic Implementation of Fast and Selective Integrin-Mediated Adhesion of Cancer Cells on Functionalized Zeolite L Monolayers. Bioconjugate Chem. 2015, 26 (9), 1873−1878. (62) De Marco, R.; Greco, A.; Calonghi, N.; Dattoli, S. D.; Baiula, M.; Spampinato, S.; Picchetti, P.; De Cola, L.; Anselmi, M.; Cipriani, F.; Gentilucci, L. Selective detection of α4β1 integrin (VLA-4)expressing cells using peptide-functionalized nanostructured materials mimicking endothelial surfaces adjacent to inflammatory sites. Peptide Sci. 2018, e23081. (63) Lin, H.-P.; Kao, C.-P.; Mou, C.-Y. Counterion and alcohol effect in the formation of mesoporous silica. Microporous Mesoporous Mater. 2001, 48 (1−3), 135−141. (64) Leontidis, E. Hofmeister anion effects on surfactant selfassembly and the formation of mesoporous solids. Curr. Opin. Colloid Interface Sci. 2002, 7 (1−2), 81−91. (65) Monnier, A.; Schüth, F.; Huo, Q.; Kumar, D.; Margolese, D.; Maxwell, R. S.; Stucky, G. D.; Krishnamurty, M.; Petroff, P.; Firouzi, A.; Janicke, M.; Chmelka, B. F. Cooperative Formation of InorganicOrganic Interfaces in the Synthesis of Silicate Mesostructures. Science 1993, 261 (5126), 1299−1303. 4174


Article

Chemistry of Materials (66) Shikata, T.; Sakaiguchi, Y.; Uragami, H.; Tamura, A.; Hirata, H. Enormously elongated cationic surfactant micelle formed in CTAB aromatic additive systems. J. Colloid Interface Sci. 1987, 119 (1), 291− 293. (67) Bachofer, S. J.; Simonis, U.; Nowicki, T. A. Orientational binding of substituted naphthoate counterions to the tetradecyltrimethylammonium bromide micellar interface. J. Phys. Chem. 1991, 95 (1), 480−488. (68) Wang, B.; Chi, C.; Shan, W.; Zhang, Y.; Ren, N.; Yang, W.; Tang, Y. Chiral Mesostructured Silica Nanofibers of MCM-41. Angew. Chem., Int. Ed. 2006, 45 (13), 2088−2090. (69) Han, Y.; Zhao, L.; Ying, J. Y. Entropy-Driven Helical Mesostructure Formation with Achiral Cationic Surfactant Templates. Adv. Mater. 2007, 19 (18), 2454−2459. (70) Qiu, H.; Che, S. Chiral mesoporous silica: Chiral construction and imprinting via cooperative self-assembly of amphiphiles and silica precursors. Chem. Soc. Rev. 2011, 40 (3), 1259−1268. (71) Yokoi, T.; Yamataka, Y.; Ara, Y.; Sato, S.; Kubota, Y.; Tatsumi, T. Synthesis of chiral mesoporous silica by using chiral anionic surfactants. Microporous Mesoporous Mater. 2007, 103 (1), 20−28. (72) Zhao, L.; Yuan, P.; Liu, N.; Hu, Y.; Zhang, Y.; Wei, G.; Zhou, L.; Zhou, X.; Wang, Y.; Yu, C. On the Equilibrium of Helical Nanostructures with Ordered Mesopores. J. Phys. Chem. B 2009, 113 (50), 16178−16183. (73) Qiu, H.; Che, S. Formation Mechanism of Achiral AmphiphileTemplated Helical Mesoporous Silicas. J. Phys. Chem. B 2008, 112 (34), 10466−10474.

4175


Morphology Control of Mesoporous Silica Particles Using Bile Acids

Recommend Documents