Biosensors are detectors based on selective molecular components of plants or animals that evolved from molecular biology and information technology. They offer applications in medical, environmental, and military/law enforcement fields. Specifically, in the 1950s Leland Clark invented an electrode to measure dissolved oxygen in blood during surgery, laying the groundwork for glucose sensors and the evolution of medical biosensors. Biosensors combine a biological compound with a transducer to detect characteristics like sensitivity, cost, reliability and more. Examples of present applications include medical care, food quality testing, environmental pollutant detection, and industrial process control.

1. Biosensors
Anthony Carr
Brett Gobe
Ben LaPierre

2. What are biosensors?
 Detectors based on selective molecular
components of plants or animals.
 Modern Biosensors evolved from 2 different
disciplines
 Molecular Biology
 Information Technology.
 Offers a wide variety of applications.
 Medical
 Environmental
 Military / Law Enforcement

4. Evolution of the Medical
Biosensor
 Mid 1950’s - Leland C Clark invents an
electrode that measures dissolved oxygen in
the blood of patients undergoing surgery.
 He surrounded a platinum electrode and
reference electrode with a plastic membrane
permeable to gases. The voltage differential
measured between the two gave the rate at
which the oxygen was being diffused.

5.  Clark extended this electrode idea to include glucose
sensors.
 However these never made their way into routine patient
care. This was due to flaws in accuracy when clots
formed around the electrode.

6. Required Characteristics
 Sensitivity  Utility
 Low detection limits  Field portability
 Cost  Ruggedness
 Simplicity  Reproducibility
 Reliability  Ease of calibration
 Speed  Stability
 Accuracy  Room for
 Precision improvement

7. Biosensors
 Combine a biological compound with a
transducer
 What is a transducer?

9. Flow Injection Analysis
(FIA)
 What is FIA?

10. Uses of Biosensors
 Environmental Monitoring
 Military
 Law Enforcement
 Medical

11. Present Applications of
Biosensors
 Medical Care (both clinical and
laboratory use)
 The determination of food quality
 The detection of environmental
pollutants
 Industrial Process Control

12. Applications (cont’d.)
 Biosensors in process control will be able to measure
materials in the process flow of temperature, pressure
and the acidity readings.
 The development of biosensors in industry can
improve manufacturing techniques, which would allow
for a wider range of sensing molecules to be
produced at a cheaper rate.
 In the field of medicine, tumor cells are used as a
biosensor to monitor chemotherapeutic drug
susceptibilities.
 Biosensors also play a role in the manufacturing of
pharmaceuticals and replacement organs such as an
artificial pancreas for diabetics.

13.  It is found that biosensors are widely used in
environmental testing by using a “flow-
through” system to monitor wastewater (a
flow-through system includes instruments
using surface plasmon resonance).
 These censors are not only restricted to the
use of molecules. Rather living
microorganisms such as bacteria can be used
to detect substances such as vitamin B12.
 Conclusively, biosensors play a part in the
field of medicine, environmental quality, and
industry mainly by identifying material and
the degree of concentration present.

14. QUESTIONS?