Guest Editorial

The importance of instrumentation systems in clinical care and medical research has been rapidly increasing in recent years. In recognition of the importance of biosensors, this Transactions planned this Special Issue devoted to biosensors. We have orga-. nized it to reflect the various classifications of biosensors that are currently of interest to researchers and clinical instrumentation designers. The first group of papers are concerned with sensors of chemical variables..We have further divided these down to sensors concerned with measuring inorganic chemicals and those that involve more complex biochemical determinations. The second group of manuscripts looks at current research in sensors of physical quantities. Following a review of applying solidstate microelectronic technology to developing this type of sensor, there are a group of papers concerned with sensors of mechanical variables. This is followed by papers which look at sensors of electrical variables. The use of new technologies to fabricate very small electrodes for special biologic applications is covered in this section. The final two papers in this issue look at more general concerns for biosensors. This includes a review of the special problems of packaging implantable sensors and a review of the applications of sensors in the field of functional neuromuscular stimulation. It is fitting that this manuscript should end this Special Issue because it not only indicates current work in the field, but also points out that biosensor research is only beginning to make its impact in the life sciences and clinical medicine. There are still many needs and applications for sensors that have not been met. We hope that through this special issue the reader can ascertain the current state of the art as well as get some idea as to future needs and directions in this important field.