Non-invasive electrochemical hand-held biosensor as diagnostic indicator of dental diseases

A new hand-held amperometric biosensor for assay of salivary peroxidase in human secretions is described. The biosensor comprises a flow through amperometric detector coupled with a micropipette, and electronics (an amplifier, peak detector, microprocessor, and display). A micropipette, amplifier, peak detector, and microprocessor have been built in-house. All operations, such as sample injection, electrochemical detection and data processing are accomplished using only one action, by pressing the plunger of the micropipette. Because the use of a peristaltic pump is completely eliminated, the consumption of both samples and reagents is significantly reduced. The biosensor has been tested as a diagnostic indicator of dental diseases. It is shown that there is a functional relationship between the total level of salivary peroxidase and the clinical status of the periodontal disease. By using commercial available kits with peroxidase-labeled conjugates, the biosensor has an excellent potential for detection of different hormones, drugs, viruses, antibodies, and bacteria.