Article pubs.acs.org/jchemeduc
Offering Remotely Triggered, Real-Time Experiments in Electrochemistry for Distance Learners Sachin Saxena and Soami P. Satsangee* Remote Electrochemistry Laboratory, University Science Instrumentation Centre, Dayalbagh Educational Institute, Dayalbagh, Agra 282005, India S Supporting Information *
ABSTRACT: Remote access to real experiments is crucial for distance learners to experience the sciences. The exploitation of technology for this purpose is advantageous in global teaching and in exchange of ideas on a single front irrespective of distance barriers. Implementation of the distance method leads to cost-effective integrated-e-learning where students at a remote location only need PCs and the Internet to perform the experiment. A remote electrochemical experiment is presented. The advantages of the remote electrochemistry laboratory for carrying out real-time experiments are discussed, and our experiences in setting up the laboratory are described. We explain how to perform the remote electrochemical experiments on the network with the main purpose of strengthening teaching in chemical sciences. KEYWORDS: Graduate Education/Research, Upper-Division Undergraduate, Analytical Chemistry, Curriculum, Distance Learning/Self Instruction, Internet/Web-Based Learning, Electrochemistry, Laboratory Computing/Interfacing
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an interest in pursuing electrochemistry. Remote experiments have been adopted by a number of universities around the world in a variety of disciplines.11In the past few years, there has been a tremendous effort in distance education in the sciences to include an online triggering phenomenon for getting a real feel of the experiment. An effective way to increase student retention of factual knowledge is through inquiry-based learning and interactivity,12 which they get from online learning, overview of virtual models, Web-based chemistry education, and remote instrumentation. This mode of teaching helps students, in a creative way, to master concepts and apply them to new context. Web-based chemistry courses foster learning and provide opportunities for students to study, generate ideas, explore, and clarify their doubts.13 Real-time experiments with the aid of networking further simplify and concretize the understanding of procedures. Nowadays, computing gadgets such as smartphones and iPads, with the help of chemistry apps, are serving as powerful and convenient educational tools.14 These portable computers, mobile phones, and Internet-capable devices can be utilized to connect to the remote laboratories and trigger the instrument from a distant location. Simulation of an experiment is based on a mathematical model and does not exactly reflect the “real” world, whereas remote access to real experiments is a challenging way of including experiments in online material.15−17 Some remote laboratories that are successfully operating in the field of sciences are • Remote control to research equipment; MALDI-TOF at University of Delaware18
istance education in sciences involves online teaching and discussion forums to address common problems on a large scale and enhance the level of understanding. For the purpose of laboratory work, real-time experiments and simulations are the approaches that are currently used. Redox chemistry is an essential part of a chemistry curriculum. It explains the oxidation−reduction, potential−current relationship, and also provides students with an enriched appreciation of the utility of intervening ideas from other branches of chemistry such as kinetics and thermodynamics.1 Electrochemical measurements play an important role in analytical chemistry as they lead to the understanding of biological redox processes occurring in the body, uses of batteries in day-to-day life, research on fuel cells, drug monitoring, electrodeposition, electroplating, and many other aspects. Chemists use electrochemical techniques for novel studies of energy, electrontransfer mechanisms, surface processes, monolayers, chemical sensors, enzyme kinetics, synthesis, electropolymerization, and other types of research.2−7 They believe that the electrochemical cells are the future energy reservoirs for sustainable development and have the capability to store surplus renewable energy in the form of electrolytic cells.8,9 Furthermore the instrumentation in electroanalysis does not require magnets, lasers, vacuum pump, or light sources. These methods do not involve multiple manipulation steps that are time-consuming or that include use of significant quantities of solvents and sophisticated analytical systems. These techniques are sensitive, selective, quick in response, and inexpensive, and they require small volumes of sample.10 In spite of these facts, electrochemistry is not emphasized in the undergraduate chemistry curriculum. Thus, by doing real-time electrochemistry experiments via the Web, students can explore this field and develop © 2014 American Chemical Society and Division of Chemical Education, Inc.
Published: February 10, 2014 368
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Figure 1. Remote instrumentation setup where a client connects to the potentiostat via port forwarding technique on the network.
• Remotely controlled laboratories for physics students (for example, wind tunnel experiment developed by Jodl and co-workers)19 • Canadian Remote Sciences Laboratory with chromatography techniques20 • The Center for Authentic Science Practice in Education (CASPIE) at Purdue University21 • Nanotechnology Applications and Career Knowledge (NACK) at Pennsylvania State University22 • Youngstown State University (YSU) Structure & Instrumentation Facility (NMR, Electron Microscopy and X-ray)23 • Integrated Laboratory Network (ILN) at Western Washington University24 • Microelectronic Device Characterization in the iLab project at MIT25 • Remotely Operated Science Experiment (ROSE) at Stanford University26 • Automated Chemical synthesis laboratory27 • NetLab remote laboratory of University of South Australia28 • Internet School Experimental System (ISES)29 These laboratories are creating teaching laboratories that follow an international curriculum. Under the MHRDNMEICT (National Mission on Education through ICT) Virtual Laboratories project30 we have setup a remote electrochemistry laboratory at Dayalbagh Educational Institute, Agra. The project has been jointly taken up by the Indian Institutes of Technology (Delhi, Kanpur, Bombay, Madras, Kharagpur, Guwahati, Roorkee), IIIT Hyderabad, Amrita University, Dayalbagh Educational Institute, NITK Surathkal, and College of Engineering, Pune. Four electrochemical experiments are briefly described that have been remotely triggered and evaluated for a global discussion on the Internet.
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a time can trigger the potentiostat remotely according to his or her time slot. The data, feedback, and registered account details are collected on the server. The feedback helps us to design and develop new sets of experiments on the Web site. The remote learning units have a simulation component at the beginning so that the students can prepare for a real experimental environment. Access to the remote experiment is based on a client−server architecture. The software used for remote connections is Windows Server 2008 with a capability of remote applications. The server controlling the laboratory is one of the main components, and the application software resides in the server. The client is a Windows XP/7 computer connected to the Internet running a standard browser and has a remote desktop client 6.1 installed for remote connections. The client remotely connecting to the server enters a user ID and password and after authentication is logged on to an application running under terminal services (TS) program. The server side of the remote laboratory has three main elements: 1. Sensorthrough which the real-world experiments are monitored and transferred with I/O hardware. 2. I/O hardwarewhich acts as a mediator between the instrument and the software by redefining the input signals, thereby measuring and generating necessary outputs. 3. Softwarefor example, Windows Server 2008 Remote Application, does the remote connection. The measurement software in our case is either the instrument manufacturer’s software or customized software prepared under .NET framework 3.5 using C#. The setup of the laboratory is diagrammed in Figure 1. The laboratory consists of a Web server and an application server connected to the instrument. The Web server and the application server are on the local area network (LAN). A router is placed as the interface between LAN and the clients who are on the Internet. The router port forwarding technique has been applied. For example, the Web server runs on port 80 (default port for Web servers). When the client connects through the Web site, a request is made at port 80 to the router and the router is programmed to forward the request to the Web server, which is at the local network.
OVERVIEW OF THE ELECTROCHEMISTRY DISTANT LEARNING
The System
The distance learning material for the course consists of several learning units with experiments in electrochemical studies following the Indian university curriculum. Only one student at 369
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Figure 2. Procedure for performing a real-time electrochemical experiment with the list of online experiments available on the Web site.
Performing an Online Experiment
A Web site31 was created for the analytical laboratory32 involving the Remote Electrochemistry Laboratory at Dayalbagh Educational Institute. The site has study material with experimental procedures, simulations for the students to prepare for a real laboratory environment, quizzes, feedback, and so forth. A student, after booking a slot, can interact remotely with an instrument, for example, a potentiostat for electrochemical experiments. The student (via the client) registers (see the video in the Supporting Information) and logs in to authenticate before getting the control of the instrument and books slots for the desired experiment as shown on the Web site (Figure 2). A student controls the instrument for 30 min. The feel of the experiment is obtained by the real-time viewing of the experiment while performing the electrochemical experiment through the live webcams in the laboratory as shown in Figure 3. Electrochemistry Lesson Design
For ease of understanding and operating the experimental as well as the instrumentation part, the structure for performing an electrochemistry experiment has been designed as shown in Figure 4. The Introduction gives an idea of the theoretical aspects of the experiment, and Setup describes the equipment used for the experiment. The Sample section gives the information about preparation of the analyte solution for analysis. The Procedure guides users in the real-time experiment. Before initiating remote triggering, Animate helps to demonstrate how to pursue the experiment and what is to be done in the next step. After a detailed review of the experiment and instrument, an authorized student can interact with the potentiostat and can perform an experiment by clicking on the Perform tab. Data Analysis details what the student needs to do with the data obtained. Quiz, pre-experiment and postexperiment, adds to the information regarding the experiment. The whole experiment can be performed using the Live View tab via webcams in the laboratory.
Figure 3. Web camera images of (A) the display panel of potentiostat and (B) an electrochemical cell on the network for real-time viewing of the experiment while performing a remote electrochemical experiment.
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SAMPLE EXPERIMENTS
Dopamine via Cyclic Voltammetry
A basic experiment in cyclic voltammetry (CV) is described. This experiment focuses on the effective analysis of 10−4 M dopamine prepared in phosphate buffer solution (pH 7.4). Initially, the student does a simulation exercise to reinforce concepts about cyclic voltammetry. The student then remotely connects to a potentiostat,33 where 20 μL of the solution is 370
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Figure 4. Structure of interface of the lesson for an electrochemical experiment.
A DPASV Experiment: Determination of Heavy Metals in the Yamuna River
dropped at a screen-printed electrode and the measurement is done through manufacturers’ application software. Full control of the potentiostat is given to the authorized client, where the student can input the parameters, run the experiment, and label the voltammogram. Figure 5 shows the electrochemical instrument setup with an experiment performed remotely, and the CV of the dopamine is displayed via interface.
In this experiment a student logs on remotely to the NOVA 1.8 version software application that gives access to the potentiostat.34 A differential pulse anodic stripping voltammetry (DPASV) technique is used for determination of metal ions in a Yamuna River water sample with a hanging mercury drop electrode. A DPASV voltammogram of a Yamuna River water sample is shown in Figure 6.
Figure 6. DPASV of a Yamuna River water sample for the effective determination of trace metals (deposition potential −1.2 V, deposition time 120 s, scan rate 50 mV/s, pulse height 0.05 V). This is the voltammogram seen on the remote viewer screen; peak labels as Cd, Pb, and Cu have been added.
Electrochemical Impedance Spectroscopy (EIS) of Circuit Equivalent to a Failing Coating on Steel Surface
EIS is a powerful technique to study the interface of the electrode surface and the bulk solution. The electrode impedance can be effectively studied using the (NOVA 1.8) application software and the potentiostat. The coating or modification at the working surface of electrode can be illustrated by the Nyquist plot explaining the changes occurring in the double charge layer and the working surface of the electrode. To study and understand the EIS we have designed a circuit that is equivalent to a failed coating at the electrode surface as shown in Figure 7. The potentiostat can be remotely accessed and triggered using remote desktop protocol.
Figure 5. (A) Electrochemical instrument setup (seen by the remote viewer through the webcam). (B) CV of dopamine in phosphate buffer solution obtained from the screen-printed carbon electrode via potentiostat and interface, where Ipa Epa and Ipc Epc are the anodic and cathodic peak current and potential, respectively (observed by the remote viewer on his or her screen). 371
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Figure 9. Comparative study of four different electrochemical solutions using different techniques via MUX explaining the analyte, voltammetric technique, and electrode used in the electrochemical setup: (A) ascorbic acidCV with screen-printed carbon electrode, (B) dopaminesquare wave voltammetry with carbon nanotube modified screen-printed carbon electrode, (C) ferri/ferro system in KCl-CV with ceramic patterned Pt electrode, and (D) acetaminophendifferential pulse voltammetry with gold nanoparticle modified screen-printed carbon electrode. (The screen will be observed by the remote viewer on his or her computer.).
Figure 7. Electrochemical impedance spectroscopy experiment where (A) the potentiostat is utilized to measure the impedance of the circuit, which is equivalent to (B) Nyquist plot explaining the circuit analogous to a failing coating at the electrode surface. (A will be seen by the viewer through webcam and spectrum B on the viewer screen.).
Comparative Studies of Electrochemical Solutions Using MUX Module
The hardware (MUX MULTI4) is used to multiplex four connections from the potentiostat (Figure 8) enabling the user
Figure 10. Potentiostat connected to four electrochemical cells with screen-printed electrodes using MUX module (seen through webcam in the laboratory).
Figure 8. MUX MULTI 4 module shown through webcam in the laboratory to remote observer. (Used to multiplex all four connections from the potentiostat. This allows sequential measurements on complete electrochemical cells.)
performing real experiments. Currently, fabrication and development of low-cost electrochemical electrodes and development of customized software for electrochemical instrument control across the Internet is in progress. In the future, chemically modified electrodes for different redox studies will be utilized for comparative studies. It is hoped that this approach of enhancing the scope of the learning with an increase in the number of fundamental experiments on the Web in the area of electrochemistry will develop a better understanding of redox chemistry at all levels and ease as well as enrich the teaching and learning process.
to study the four electrochemical cells at a time observed from the viewer side. It connects with the potentiostat and adds up to the remote triggering phenomenon. The client has a choice of studying four electrochemical solutions sequentially with the same or different kinds of electrodes (Figures 9 and 10). The flexibility with the software (NOVA 1.8) of choosing four different techniques using MUX MULTI4 module extends the coverage of study for the client in the area of electrochemistry. The voltammograms will be observed on the viewer screen. Another advantage of MUX is its compatibility with the other hardware systems. Screen-printed patterned and ceramic electrodes35 (commercially available screen-printed electrodes) can also be connected through an interface to the potentiostat using MUX.
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CONCLUSIONS Remote control of sophisticated instruments motivates students and generates a creative self-learning environment. There are many upcoming institutions in villages (in remote areas) and distance universities (recently established) lacking instrumentation. Distant learning experiments have been used through remote application to help students understand the basics of electrochemistry by running the fundamental experiments online that they might have done in the laboratory. Students
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FUTURE WORK We are directing our efforts to increase the number of online experiments in the area of electrochemistry and to help the students become aware of and avail themselves of user-friendly procedures of connecting to the electrochemical laboratory for 372
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(11) Kennepohl, D.; Shaw, L. Accessible Elements- Teaching Science Online and at a Distance; Athabasca University Press: Athabasca University: Edmonton, 2010; pp 167−173. (12) Bolotin, M. M. Increasing interactivity and authenticity of chemistry instruction through Data Acquisition Systems and other technologies. J. Chem. Educ. 2012, 89, 477−481. (13) Dori, Y. J.; Barak, M.; Adir, N. A web based chemistry course as a means to foster freshmen learning. J. Chem. Educ. 2003, 80, 1084− 1092. (14) Libman, D.; Huang, L. Chemistry on the go: Review of Chemistry Apps on Smartphones. J. Chem. Educ. 2013, 90, 320−325. (15) Kennepohl, D.; Baran, J.; Connors, M.; Quigley, K.; Currie, R. Remote Access to Instrumental Analysis for Distance Education in Science. IRRODL 2005, 6, 3. (16) Baran, J.; Currie, R.; Kennepohl, D. Remote Instrumentation for the Teaching Laboratory. J. Chem. Educ. 2004, 81, 1814−1816. (17) Kennepohl, D. Remote Teaching Laboratories in Science and Engineering. Encyclopedia of Distance Learning, 2nd ed.; IGI Global: 2009; Vol. III, pp 1749−1753. (18) University of Delaware. http://corefacilities.dbi.udel.edu/ facility/mass-spectrometry-core-facility (accessed January 2014). (19) Remotely Controlled Laboratories (RCLs). http://rcl.physik. uni-kl.de/ (accessed Jan 2014). (20) Canadian Remote Sciences Laboratory. http://www.remotelab. ca (accessed January 2014). (21) The Center for Authentic Science Practice in Education (CASPIE) at Purdue University. http://www.purdue.edu/ discoverypark/caspie/ (accessed January 2014). (22) Nanotechnology Applications and Career Knowledge (NACK) at Pennsylvania State University. http://nano4me.org/remoteaccess. php (accessed January 2014). (23) Youngstown State University (YSU) Structure & Instrumentation Facility (NMR, Electron Microscopy). http://web.ysu.edu/gen/ stem/YSU_Structure__Instrumentation_Facility_m1362.html (accessed January 2014). (24) Integrated Laboratory Network (ILN) at Western Washington University. http://www.wwu.edu/iln/ (accessed January 2014) (25) MIT iCampus. http://icampus.mit.edu/iLabs/ (accessed January 2014). (26) ROSE at Stanford University. http://gse-it.stanford.edu/ research/project/rose (accessed January 2014). (27) Godfrey, A.; Masquelin, T.; Hemmerle, H. A remote-controlled adaptive medchem lab: an innovative approach to enable drug discovery in the 21st Century. Drug Discovery Today 2013, 18, 795− 802. (28) NetLab. http://netlab.unisa.edu.au/index.xhtml (accessed January 2014). (29) Internet School Experimental System. http://www.ises.info/ index.php/en (accessed January 2014). (30) Virtual Labs. http://www.vlab.co.in/ (accessed January 2014). (31) Laboratory at Dayalbagh Educational Institute. http://220.227. 100.58 (accessed January 2014). (32) Satsangee, S. P.; Mohd, R.; Gandhi, R. Remote Electroanalytical Laboratory. iJOE 2011, 1, 40−43. (33) DropSens. http://www.Dropsens.com (accessed January 2014). (34) Metrohm autolab B.V. http://www.ecochemie.nl/ (accessed January 2014). (35) Pine Research Instrumentation. http://www.pineinst.com/ echem/viewproduct.asp?ID=46681 (accessed January 2014).
can connect to the laboratory and perform an experiment with just a computer and the Internet. Via an initiative to start electrochemistry at distance, we have started nodal centers with a number of institutions for the students to interact and utilize these experiments in their daily curriculum. Students have given their feedback and ideas for involving the number of experiments and type of voltammetric experiments in the experiment list. This supports the main idea to involve students in the process. However, creating an online laboratory for chemistry is a challenge as a number of manual tasks must be automated. Work is in progress in this direction.
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ASSOCIATED CONTENT
* Supporting Information S
A video outlining how to register for getting scheduled and perform the remote electrochemical experiments. This material is available via the Internet at http://pubs.acs.org.
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AUTHOR INFORMATION
Corresponding Author
*E-mail:
[email protected]. Notes
The authors declare no competing financial interest.
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ACKNOWLEDGMENTS The authors gratefully acknowledge the financial support obtained from M.H.R.D, India, under NMEICT project for setting up the Electroanalytical Laboratory.
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