Description of Instrumentation and Procedures - Advances in Biochemical Engineering Biotechnology - page 28

and - finally - to 1 10 -8 M with the dual recycling system, corresponding to an

overall 1700-fold multiplication.
The use of an enzyme thermistor as a specific detector for monitoring diffe-
rent enzymes [17, 63, 45] in the eluents from chromatographic procedures had
the advantage of being applicable in optically dense solutions, where spectro-
photometric methods fail, and of being able to operate on-line for discrete
samples.
In 1988, Flygare et al. [39] made use of the ability of enzymes to function as
catalysts in organic solvents. Performing the biosensor analysis in these solvents
with improved substrate and product solubilities sometimes changed the sub-
strate specificity of the enzyme to a specific substrate, or even led to new by-pro-
ducts. A specific advantage for thermal analysis in organic solvents was their
lower heat capacity and higher thermal expansion coefficient, leading to a large
gain in sensitivity [65].
Flygare et al. [40] also used the enzyme thermistor for the control of an
affinity purification. Here, lactate dehydrogenase (LDH) was recovered from a
solution by binding to a special Sepharose gel (AMT-sepharose). The addition of
the gel to the solution was controlled by a PID controller or a desktop computer,
according to the amount of unbound LDH detected with the enzyme thermistor.
Both systems enabled rapid and accurate assessment of the correct addition of
the adsorbent.

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4
Future Developments

4.1
Telemedicine

The rapid advances in microelectronic technology have resulted in revolution-
izing the field of information technology. Today, computers and communication
facilities offer a number of possibilities for upgrading our everyday life and
work. It may also affect our life with respect to healthcare. Such advances in
information technology can be intelligently utilized in tele-medical monitoring
and in diagnostic systems for decentralized use.
These systems would be able to fulfil functions, such as health monitoring,
routine check-up, clinical diagnosis, and to provide medical advice. They could
take over a role in the primary healthcare of humans and make it convenient for
medical practitioners to assess and treat the diseases instantly. As patients can
be easily linked to a central diagnostic and monitoring facility through the tele-
communication network,they can avail themselves of it either at home or during
travel. This technology is of strategic importance, as it can reduce the cost of
healthcare, and improve the quality of life by creating a more secure and healthy
environment.
This technology has been launched in some countries, where physiological
parameters are at present being collected by physicians from remote locations.
In general, telemedicine is a broad concept that includes not only transfer of
medical documents, such as X-ray film, but - more importantly - connection