Development of a sandwich format, amperometric screen-printed uric acid biosensor for urine analysis.
A screen-printed carbon electrode (SPCE) incorporating the electrocatalyst cobalt phthalocyanine (CoPC), fabricated using a water-based ink formulation, has been investigated as the base transducer for a uric acid biosensor. A sandwich biosensor was fabricated by first depositing cellulose acetate (CA) onto this transducer (CoPC-SPCE), followed by uricase (UOX) and finally a polycarbonate (PC) membrane; this device is designated PC-UOX-CA-CoPC-SPCE. This biosensor was used in conjunction with chronoamperometry to optimize the conditions for the analysis of urine: temperature, 35°C; buffer, pH 9.2; ionic strength, 50 mM; uricase, 0.6 U; incubation time, 180 s. The proposed biosensor was applied to urine from a healthy subject. The precision determined on unspiked urine (n=6) was 5.82%. Urine was fortified with 0.225 mM UA, and the resulting precision and recovery were 4.21 and 97.3%, respectively. The linear working range of the biosensor was found to be 0.015 to 0.25 mM (the former represents the detection limit), and the sensitivity was calculated to be 2.10 μA/mM.
Centre for Research in Biosciences, University of the West of England, Frenchay Campus, Bristol BS16 1QY, UK.
P
P
Kanyong
R M
RM
Pemberton
S K
SK
Jackson
J P
JP
Hart
D015374:Biosensing Techniques / Q000295:instrumentation* / Q000379:methods*; D002021:Buffers; D002138:Calibration; D004563:Electrochemistry / Q000295:instrumentation* / Q000379:methods*; D006801:Humans; D014527:Uric Acid / Q000652:urine*; D016482:Urinalysis / Q000295:instrumentation* / Q000379:methods*
D002021:Buffers; D014527:Uric Acid