Engineering and instrumentation in biotechnology

Discusses the development of biosensing devices which runs parallel to activities in physical measurement techniques. Biosensors rely on interfacial properties (electro-optic and electro-chemical) and require direct contact with the sample. Surface electrode arrays are sensitised to particular analytes by the deposition of suitable affinity and electron mediation compounds. Devices based on ferrocene as an electron transfer mediator in glucose- oxidase modified carbon electrodes have operated successfully in fermentation monitoring. Laser optical techniques are also developing as powerful analytical tools in bioprocessing and product assay. Photon correlation spectroscopy determines cell size and population distributions by monitoring the diffusion properties of particles undergoing Brownian motion. Immunological processes have been studied as well as cell morphology, proteins and other high molecular weight materials. Innovative approaches are also evident in the current studies aimed at selective filtration of suspensions