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LABORATORY PROFILE A virtual service Phil Williams is a rare breed, a freely altruistic scientist who, with a team at the University of Nottingham (U.K.), has developed a virtual laboratory that everyone can use at great expense to the team in terms of time, money, and effort, but at zero cost to the user. He and his colleagues in the Laboratory of Biophysics and Surface Analysis in the Department of Pharmaceutical Sciences have developed the first interactive system based on the World Wide Web for analyzing and improving surface images from scanning probe microscopy (SPM). The system has been a resounding success—scientists around the world are queuing up to enter their data and extract an enhanced image. How does the system work? The system is simplicity itself from the users' point of view—they just up-load raw image data via the Web site. The server uses designer software to convert the many different output types from a variety of microscopes. Although the system is not yet perfect, it could point the way to a new way of processing analytical data. At die top of Williams's wish list, however, is standardization among software (and instrument) vendors. "Wouldn't it be nice to share not only data, but also software, between computers and instruments? I could sit at a scanning electron microscope, gather an image, process it using software written in Germany on the corporate mainframe in the USA and then compare graphically on my screen die image from a confocal laboratory in Australia." Although agreement between companies remains elusive, Williams and his colleagues, Martyn Davies, Saul
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Tendler, and Clive Roberts, hope their approach to software for SPM will lead the way in analytical processing. "Running processing software on one machine is limiting," explains Williams. "The ideal is to have transparent software which runs 'on the net' and utilizes all the [processors] that are available. These can be local machines (on your desktop), or remote servers such as ours. You use the software, get the results, and are not really bothered about where the processing occurred providing it is secure and fast." Williams's approach has broad implications for analytical science. As a submicrometer-resolution surface imaging technique, SPM has wide applications. It works in almost any environment, even under liquid, but, importantly, it encompasses many imaging mechanisms, including molecular electronic and optical properties. SPM is not without problems. The image is distorted by the size of die sampling spot (the tip). This distortion is not easily resolved because it is nonlinear, and the shape of die sampling spot is unknown. Williams and his colleagues' software routines can process SPM data to remove the distortions where possible. This, he says, permits an accurate assessment of the "trueness" of the data or how well the image represents the sample. The software then allows researchers to calculate many properties from the images and follow dynamic processes, such as polymer degradation, protein adsorption, and crystal growth. These time-lapsed data can then be correlated with surface plasmon resonance, diin-film microbalance, and fluorescence measurements. The next process in line for the online treatment is one-dimensional data. "We have X-ray photoelectron peak-fitting software which would integrate nicely," adds Williams, "as well as maximum entropy software tiiat we could apply to NMR" In pharmaceutical science, literally thousands of scientists use SPM, many of them looking at biological and polymeric systems. The Nottingham lab has concentrated on making itself a leader in the field of fundamental molecular structure and function. The researchers there study proteins associated with disease and drug tiierapy, protein-ligand and antibodyantigen forces of interaction
Analytical Chemistry News & Features, December 1, 1997
combinatorial chemistry (mapping of interactions over large areas and chemical sensing on the nanoscale), polymeric systems (drug delivery mechanisms, biodegradable polymers), polymer-protein interactions for biomedical devices and implants, and biosensors. They apply a raft of techniques such as SPM, static secondary ion MS, X-ray photoelectron spectroscopy, FT-IR spectroscopy, scanning and tunneling electron microscopies, microcalorimetry and electrorotation assay. "SPM " explains ^^illicims "provides one important piece of the jigsaw AVe see die SPM server as a stepping stone towards software to enhance all the other analytical techniques " Truly altruistic? From the scientific standpoint, by allowing other groups to use their software with their own data, the Williams team gets the chance to apply routines to data that they would otherwise not have access to. "We don't actually see their data," Williams explains. "It's not stored or archived. We don't even know who the people are, but we do get vital feedback from users." Williams and his colleagues have money until year-end. "We are looking for funding to continue this as we are near the end of our current grant," he says. Additional information on the SPM server can be found at http://pharm6. pharm.nottingham.ac.uk/processing/ main.html or http://128.243.60.6/ processing/main.html. David Bradley Recommended reading Chen, X.; Davies, M.; Roberts, C. J.; Shakesheff, K. M.; Tendler, S.J.B.; Williams, P. M. Anal Chem. .996, 68, 1451-55. Williams, P. M.; Davies, M. C; Roberts, C. J.; Tendler, S.J.B. Analyst t997, 122,1001-06.
