Development and study of an amperometric biosensor for the in vitro measurement of low concentration of putrescine in blood.
An amperometric biosensor was developed for the in vitro determination of putrescine in blood samples because elevated level of putrescine in blood can be a diagnostic indicator of certain kinds of cancer. The electrochemical transducer consisted of a flat form, three electrode amperometric micro-cell fabricated with thin film photolithography on flexible Kapton substrate. An immobilized putrescine oxidase (PUO) layer provided the biocatalytic oxidation of the putrescine, while the generated hydrogen peroxide was detected on the platinum-working electrode. An electropolymerized poly(m-phenylenediamine) (pPDA) size-exclusion layer was used to protect the working electrode from fouling and to prevent signal generation by common electroactive interferents present in blood. The preparation of the biocatalytic enzyme- and outer protective layers was optimized for improved sensitivity and response time. A detection limit of 50 nM was achieved in pH-adjusted whole blood samples, which is below pathological levels.
Nagy
Livia
L
Hungarian Academy of Sciences, Research Group for Chemical Sensors, Ifjúság u.6, 7624 Pécs, Hungary.
Nagy
Géza
G
Gyurcsányi
Róbert E
RE
Neuman
Michael R
MR
Lindner
Erno
E
D015374:Biosensing Techniques; D001774:Blood Chemical Analysis / Q000295:instrumentation / Q000379:methods; D004563:Electrochemistry / Q000295:instrumentation* / Q000379:methods; D004800:Enzymes, Immobilized / Q000737:chemistry; D004867:Equipment Design; D006801:Humans; D006861:Hydrogen Peroxide / Q000032:analysis / Q000138:chemical synthesis; D008832:Microchemistry / Q000379:methods; D008839:Microelectrodes; D015336:Molecular Probe Techniques; D000587:Oxidoreductases Acting on CH-NH Group Donors / Q000737:chemistry; D011700:Putrescine / Q000097:blood* / Q000737:chemistry; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014159:Transducers
D004800:Enzymes, Immobilized; D006861:Hydrogen Peroxide; C022488:putrescine oxidase; D000587:Oxidoreductases Acting on CH-NH Group Donors; D011700:Putrescine