Biopolym. Cell. 1996; 12(4):25-30.
A proteolytic biosensor based on a pH-sensititive field effect transistor. II. Investigation of operation in model solutions
1Beloivan O. A., 1Soldatkin A. P., 2Starodub N. F., 1El'skaya A. V.
  1. Institute of Molecular Biology and Genetics, NAS of Ukraine
    150, Akademika Zabolotnoho Str., Kyiv, Ukraine, 03680
  2. Palladin Institute of Biochemistry, NAS of Ukraine
    9, Leontovycha Str., Kyiv, Ukraine, 01601


The laboratory prototype of biosensor has been fabricated on the basis of trypsin immobilized on the gate surface of pH-sensitive field effect transistor which should be useful for detection of the total protein concentration in biological fluids. The optimal conditions to provide marswements have been determined. The characteristics of its operation stability and accuracy in a model system have been obtained. The biosensor prototype can measure concentrations of Na-benzoil-arginin ethyl ester in the range of 0.2-3.0 mM. The effects of pH, buffer capacity and ionic strength on the response of the biosensor have been investigated. All the results have been discussed in frame of the problem of detecting total protein concentration in biological fluids.


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