As a result of the accomplishments in biosensor research over the past 30 years, it is simple to use immobilized enzymes to fabricate electrodes of various materials, sizes, and forms. In addition, scientists have a greater theoretical understanding of parameters such as enzyme activity and diffusion properties that influence sensor response. We have summarized the most important design parameters in Table III. We know which technologies (including membrane fabrication, screen printing, and photolithographic techniques such as thin-film methods) are, in principle, suitable for the mass production of enzyme electrodes. This knowledge has led to the commercialization of enzyme analyzers that are used mainly for glucose or lactate determination. But there are still many parameters that must be improved to achieve reproducible fabrication of sensors applicable to other fields. For example, the electron transfer between enzyme and electrode has to be improved before reagentless, implantable sensors can be fabricated. Another active area of research is in the development of easy-to-use small immunosensors. Commercialization of these devices will be achieved only when attention to their manufacturing aspects is accelerated. © 1993, American Chemical Society. All rights reserved.
