Amperometric biosensors based on redox enzymes

摘要

The invention includes various prototypical amperometric biosensors for the quantification of biological substrates such as fructose, creatinine, creatine, and sarcosine, and the methods for producing these biosensors. Also included in the invention is a minaturized version of the biosensing devices. The components of these prototypical biosensors are immobilized on a self-assembled monolayer (SAM) comprising chemisorbed alkanethiols. The deposition of an amphiphilic lipid layer to these systems increases the stability and activity of the resultant biosensor and enhances the rejection of many interferents. An additional feature of the invention is the co-deposition of the components of the sensor via a novel detergent dialysis protocol. The invention features two particular biosensor systems. One embodiment involves fructose dehydrogenase as the redox/sensor enzyme and fructose as the substrate/analyte. Another embodiment involves the measurement of the substrates/analytes, creatinine, creatine and sarcosine, using sacrosine dehydrogenase as the redox/sensor enzyme, with the involvement of creatinine amidohydrolase and/or creatine amidinohydrolase in the reaction pathway.