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Fructose biosensor based on d-fructose dehydrogenase immobilised on a ferrocene-embedded cellulose acetate membrane

2001; Elsevier BV; Volume: 439; Issue: 1 Linguagem: Inglês

10.1016/s0003-2670(01)01021-2

1873-4324

Ján Tkáč, Igor Voštiar, Ernest Šturdı́k, Peter Gemeiner, Vladimı́r Mastihuba, J. Annus,

Advanced biosensing and bioanalysis techniques

The prevention of ferrocene leakage from an electrode by physical retention of mediator in a cellulose acetate membrane matrix is reported here for the first time. Five types of cellulose acetate membranes were prepared, containing 1.8, 5.3, 8.5, and 20.0% of ferrocene and a membrane containing 1.8% of ferrocene and 0.05% of Nafion® in the matrix. All the membranes tested, including a cellulose acetate membrane without ferrocene, were much more resistant to ascorbate interference (12–69 nA mM−1) in comparison to an uncovered glassy carbon electrode (1152 nA mM−1). With increasing amount of ferrocene in the membrane, a decreasing ability of the membrane to retain mediator was observed. Ferrocene-embedded membranes were successfully applied in the construction of a fructose biosensor by immobilisation of PQQ-dependent fructose dehydrogenase. A biosensor with a membrane containing 20.0% of ferrocene in the matrix exhibited the lowest detection limit (3 μM), the shortest response time (45 s) and the highest sensitivity (232 nA mM−1). However, this biosensor was unstable because of ferrocene leaching and after 9 h of continuous use only 15% of the initial activity was observed. The biosensor with a cellulose acetate membrane containing 1.8% of ferrocene and 0.05% of Nafion® had better stability characteristics, and retained almost 40% of the initial response after 8 h of continuous use, with similar sensitivity (226 nA mM−1) and response time (75 s).