Prussian Blue bulk modified screen-printed electrodes for H2O2 detection and for biosensors

A sensor for H2O2 amperometric detection based on a Prussian Blue (PB) bulk modified carbon screen-printed electrode was developed. It has been optimi sed with respect to the lowest limit of detection achieved. PB was made che mically by the reaction of FeCl3 with K-4[Fe(CN)(6)]. The resulting powder, obtained by forced crystallisation induced by acetone, was dried and activ ated at 150 degreesC for 10 h. PB microparticles (< 38 mum) were prepared a nd mixed with carbon ink. The limit of detection achieved was 0.4 muM with the linear range up to 100 muM of H2O2 with the sensitivity of 137 muA mM(- 1) cm(-1), that was comparable with sensors based on electrodeposited PB fi lm. The transducer was applied for a glucose biosensor, that exhibited LOD of 0.22 mM, linear range up to 3 mM, K, K-M(app) of 4.6 mM, and the sensiti vity of 3.21 +/- 0.16 muA mM(-1) cm(-1). The peroxide sensor, as well as th e glucose biosensor, were totally insensitive to oxygen, ascorbate, urate, and paracetamol. (C) 2001 Elsevier Science B.V. All rights reserved.