Remote Instrumentation for the Teaching ... - ACS Publications


Remote Instrumentation for the Teaching...

1 downloads 119 Views 87KB Size

Information



Textbooks



Media



Resources edited by

Teaching with Technology

Gabriela C. Weaver Purdue University West Lafayette, IN 47907

Remote Instrumentation for the Teaching Laboratory

W

Jit Baran and Ron Currie Chemical Technology, Northern Alberta Institute of Technology, 11762 106th St., Edmonton, Alberta, Canada, T5G 2R1 Dietmar Kennepohl* Centre for Science, Athabasca University, 1 University Drive, Athabasca, Alberta, Canada, T9S 3A3; *[email protected]

Modern instrumental methods of analysis involve the computer in four major roles: controlling instrument setpoints, acquiring data, analyzing data, and presenting data. Virtually all instrumental analyses in industry are now controlled using software provided by the instrument manufacturer to operate in this manner. This common feature affords the opportunity of connecting to an instrument’s computer via a telephone modem or the Internet to provide access from remote locations. A vendor-specific software program on the host computer allows the instrument to be effectively controlled and instrumental analysis to be performed in real time from a remote location. Only a browser is needed at the re-

mote location. Knowledge and hands-on experience with analytical instrumentation is a necessary component of the educational background of any chemist today. Remote operation of equipment has long been developing in areas such as space research or for military applications. Scientists are also increasingly exploring the use of remote control for more hazardous experiments or for sharing expensive equipment and facilities with other researchers (1). More recently, with the availability of the World Wide Web, educators in the disciplines of biology, chemistry, physics, and engineering, which traditionally have a strong laboratory component, are exploring the integration of real Web-based experiments into online courses (2). In many instances, the online laboratory components are simulated and offer socalled virtual laboratory experiences (3). Unlike virtual or simulated analytical instruments, remote control of equipment and experiments allows students or researchers to physically carry out real experiments over the Web (4, 5). Not suprisingly, reporting of many of these initiatives is also Webbased; conventional literature citations in this subject area are relatively sparse. The objective of this pilot project was to investigate the feasibility of using current software, such as PC-Duo, PCAnywhere, or LabVIEW, in training students in instrumental analysis from a remote location. Several others have already reported using LabVIEW software system for controlling instrumentation and acquiring data in an in-class teaching environment (5, 6). Remote Access to Analytical Instruments As shown in Figure 1, several analytical instruments were connected in a local area network (LAN) for a total of 15 stations: HP5890 GC, HP5890/5971 GC–MSD, Varian AA 100, Varian AA220, two Varian 3400 GC, two Varian 3800/ 8400 LC, two Nicolet FTIR, two Helios UV–vis, two Varian LC 9012/9050/9065, and Dionex IC. An Internet security accelerator server (reverse publisher server) was set up to permit access to this LAN over a firewall using terminal emulation software. PC-Duo software was adopted for the terminal emulation to allow control of the desktop of a computer operating an instrument within that LAN. One advantage of this arrangement is that the bulk of the software required resides with the institution rather than on the remote workstation. Students or guests accessing any of the instruments would only require an Internet browser at their locations. After we set up

Figure 1. Remote Analytical Instrument Access

1814

Journal of Chemical Education



Vol. 81 No. 12 December 2004



www.JCE.DivCHED.org

Information

our system, chemistry colleagues around the globe (including a lecturer from the Chemistry Department at the University of Otago in New Zealand) successfully accessed our instruments in Canada to carry out entire experiments. Remote instrumentation has been integrated for specific experiments within the regular teaching laboratory as a pilot project; the methods included gas chromatography (GC), FTIR spectroscopy, and UV–vis spectrophotometry. Typically students receive hands-on laboratory training sessions in methods of calibration standard and sample solution preparation on site. Once solutions have been prepared the vials containing the standards and samples are placed in the auto-sampler or autoinjector. They can now be analyzed by students on site or remotely. Logins and passwords are assigned to students to allow them access and physical control of the instrument at scheduled times. The onscreen workstation environment is identical for operators, whether they are working down the hall, off-campus, or right beside the instrument itself. Students taking the Project Management course (CH490L) and Advanced Analytical Chemistry (CH464L) courses in the Chemical Technology Program at NAIT carried out experiments remotely on FTIR and GC instruments, while several first-year Athabasca University chemistry students (CHEM 217) used a UV–vis spectrophotometer and Beer’s Law to analyze their acetylsalicylic acid samples at a distance. FTIR Spectroscopy During the pilot study, one group of four students in CH490L at Northern Alberta Institute of Technology (NAIT) was investigating methods of assessing product quality for a proprietary compound manufactured by a small local company using FTIR. Some of the potential impurities and final product were very moisture labile and required the preparation of standards and mixtures of possible impurities in the product to be completed under an inert atmosphere of Ar. Since this required considerable amounts of laboratory time, the close examination of the spectra acquired could not be completed during the assigned laboratory period. Additionally, functional group interaction between the product and impurities caused peak shifts that made potential absorption bands for quantification undesirable. In an attempt to identify potential absorption bands unique to the product and impurities, several spectral overlays were required. The opportunity to access the spectra outside of the laboratory period allowed the students the time to thoroughly investigate the potential of this method in assessing product quality. Gas Chromatography The second CH490L group project (with four students) was a method validation study for the analysis of malathion using free induction decay (FID) and pulsed flame photometric detection (PFPD) on a Varian 3800 GC. These students had the advantage of an autosampler that allowed the students to initiate data acquisition remotely via a sequence list once the samples were prepared and placed in the correct vial positions. This form of automation allowed large amounts of data to be acquired outside of the assigned laboratory period with most of the scheduled laboratory time devoted to data analysis and interpretation of the data. www.JCE.DivCHED.org





Textbooks



Media



Resources

Another example of the options available in a teaching laboratory was illustrated unexpectedly within the Advanced Analytical Chemistry course (CH464L). During an assigned laboratory period, problems developed with the instrument that meant that two students were unable to complete data acquisition for the experiment in class. The opportunity to access the GC remotely enabled data acquisition to be performed outside of the laboratory period using a sequence list and an autosampler. This allowed the students to analyze their own data without having to perform the exercise using data from other students. UV–Vis Spectrophotometry Athabasca University (AU) students complete their courses entirely through online and distance education. The laboratory component of the CHEM 217 is partly conducted through home-study laboratory kits in addition to more conventional supervised laboratories (7). In the pilot study experiment six students in the supervised laboratories prepared a series of standard solutions of tetraaquasalicylatoiron(III) ion by reacting acetylsalicylic acid with base, acidifying the solution, and then allowing the anion so formed to react with FeCl3·6H2O. In contrast to the colorless acetylsalicylic acid, the tetraaquasalicylatoiron(III) solution absorbs strongly in the visible range (λmax = 520–525 nm). The concept of the Beer–Lambert law relating solution absorbance with concentration is introduced. Using a Helios UV–vis spectrophotometer students measure absorbance at λmax and then plot that absorbance against solution concentration for the standards to create a linear calibration curve. They are then given an aspirin tablet and asked to determine the amount of acetylsalicylic acid it contains. Students dissolve the tablet in a hot NaOH solution and then produce the iron(III) complex. Measuring its absorbance they use their own calibration curve to determine the concentration of the iron(III) complex in solution and calculate the amount of acetylsalicylic acid that must have been in that tablet versus the quantity of filler. Students were divided into two groups for the pilot study. Both groups did all their wet chemistry in the supervised laboratory. The control group carried out their measurements on the spectrophotometer on site, while the second group left their unknown and standard samples to be loaded on an autosampler tray and did their measurements remotely. Assessment of Remote Laboratory Access Little measurable difference in performance with these experiments was observed for students on site compared to students working remotely. A survey of these students showed that they found the instrument access to be both flexible and convenient. A comment from one of the students emphasizes an advantage of remote access: “Lab time is almost always short but with remote access one can concentrate on data collection while in the laboratory and analysis while in the office or at home.” In fact, on site and remote access were essentially seen as being equivalent. (The remote access involved only one extra login compared with on site access.) There were two concerns raised in the student surveys. The NAIT students had some trepidation with correcting mechanical problems when accessing the instrument remotely.

Vol. 81 No. 12 December 2004



Journal of Chemical Education

1815

Information



Textbooks



Media



Resources

Although mechanical problems were not actually experienced, students did have some anxiety about how they would be able to deal with this problem if it occurred. The AU students noted that learning the instrument interface, whether on site or remotely, was too much to ask for an experiment in a general first-year chemistry course. Indeed, using remote access may be more suitable for teaching more senior analytical chemistry students rather than students in a general first-year chemistry course. In all cases, the comments did underscore the importance of a user-friendly Web site that contains a high-quality instructional component so that students learn and are comfortable with the chemical principles involved, the instrument operation, and the computer interface used when accessing analytical instruments from a remote site. Time in the teaching laboratory where analytical instruments are shared among several students is always at a premium. Our pilot study has shown that remote access offers a great deal of flexibility and convenience for the student and instructor alike. The student can alter experimental parameters, run a real experiment, analyze data collected, and prepare reports both within the supervised teaching laboratory and outside regular hours. This additional freedom fosters a more problem-solving laboratory environment by allowing the student more opportunities for experimentation and exploration. Ironically, the discussion of computer laboratory simulations or virtual laboratories for teaching invariably brings up the importance of incorporating some errors in the data or allowing the student to make mistakes in the experiments to mimic real life events. We do not have to try to create these. Since almost all current analytical instruments are computer controlled, exposure and practical experience with computer-controlled instruments, including remote access, is a big plus for the student. Others have already underscored the importance of early introduction to modern instrumental methods at the undergraduate level (5). Remote access has also afforded unexpected advantages for the instructor. Upgrades to instrumental software and hardware require frequent changes to instrumental analysis coursepacks or laboratory manuals. Access to the instruments via the Internet has made these upgrades much easier. Staff can access the instruments and the key screens needed to utilize the instrumental software can be captured and pasted into the coursepack document on their office computer. Additionally, student files can be accessed and checked for consistency with reports submitted for marking from the office computer. Multiple user access to the Web site permits an instructor to observe students using instruments in the laboratory via remote access and to intervene when help is requested using a chat tool. Conclusion Although the pilot study has shown the viability of this concept, more research is required to adapt this technology to a teaching environment that would allow students both facile access to instrumental science experiments and an advantageous route to upgrade their laboratory skills at a distance. Creation of online features will be crucial to the use and learning by students. In particular, the development of a suitable Web site, which provides an easy-to-use interface 1816

Journal of Chemical Education



to the instrumentation, will be critical. These would include features such as student access to a tutorial clarifying the objectives and theory behind the experiment, provisions for a virtual laboratory setting that will allow a student to practice the experiment before going online in a real-time setting, a qualifier tool that will ensure students have the skills to actually operate the equipment before going online, a scheduler that would organize and control access to particular instruments, and further development of a chat tool to permit student–instructor interaction when necessary. Additionally, Web site provision of streaming video and audio would enable direct, real-time communication in the tutorials about theory as well as equipment operation. Further advances could include an audio or videoconferencing system to permit enhanced instructor–student interaction, making the learning experience more enjoyable and human. In instrumental analysis applications, access to a variety of databases (e.g., spectral and mass spectrometry databases) would be provided to aid in compound identification. Other approaches to facilitating training on the Web site would be a site for frequently asked questions coupled with a troubleshooting flowchart or decision tree to help students solve some difficulties involving access to instrumentation and the process of instruction. This would be particularly important to guide students accessing the site for the first time when the need for guidance is most critical. Acknowledgments We thank Kieron Quigely (NAIT) for technical support, Robert Carmichael (AU) and Allan Blackman of the University of Otago for their assistance in carrying out UV–vis experiments remotely, and Alberta’s Learning Enhancement Envelope for funding for this pilot study. W

Supplemental Material

Technical details of the remote access system used and an illustrated lab manual for students are available in this issue of JCE Online. Literature Cited 1. Krause, C. Oak Ridge National Laboratory Review 1997, 30 (3/4); http://www.ornl.gov/info/ornlreview/v30n3-4/ remote.htm (accessed Aug 2004). 2. Hesselink, L.; Rizal, D.; Bjornson, E. CyberLab: Remote access to laboratories through the World Wide Web. http:// gunther.smeal.psu.edu/cachedpage/3339/1 (accessed Aug 2004). 3. Kennepohl, D. J. Dist. Educ. 2001, 16 (2), 58–65. 4. Bassem, A.; Hamza, M. K.; Hsu, S.; Romance, N. Virtual Labs versus Remote Labs: Between Myth and Reality. http://www.cse.fau.edu/~bassem/Publications/Pub-22-CFLHEC1998-DearField.PDF (accessed Aug 2004). 5. Drew, S. M. J. Chem. Educ. 1996, 73, 1107–1111. 6. Gostowski, R. J. Chem. Educ. 1996, 73, 1103–1106; Haines, R. S. J. Chem. Educ. 1998, 75, 785–787; Spanoghe, P.; Cocquyt, J.; Van der Meeren, P. J. Chem. Educ. 2001, 78, 338– 342. 7. Kennepohl, D. J. Chem. Educ. 1996, 73, 938–939.

Vol. 81 No. 12 December 2004



www.JCE.DivCHED.org