A new Screen-printed electrodes (SPE) integrated in one channel flow-cell was developed. The one channel flow-cell is attached and directly changeable with electrode. In the new flow-cell the injection is done through an "in-line luer injection port" which can be less aggressive than wall-jet flow cell for a biological recognition element immobilized on the surface of the electrode. The sample volume can be easily controlled by the operator through a syringe. In this novel thin layer flow-cell screen-printed electrodes, the working electrode was modified with graphene materials, and an enhancement of electroactive area to 388% over a standard electrode was found. This new configuration was applied to study the entrapped cellobiose dehydrogenase from the ascomycete Corynascus thermophilus (CtCDH) in a photocrosslinkable PVA-based polymer. The calibration curve of lactose using optimized parameters shows a wide linear measurement ranges between 0.25 and 5mM. A good operational stability of the CtCDH-PVA-modified graphene electrode is obtained, which keeps the same initial activity during 8h and exhibits a good storage stability with a decrease of only 9% in analytical response after 3 months storage at 4◦C.
Keywords: Cellobiose dehydrogenase; Direct electron transfer; Flow injection analysis; Graphene nanomaterials; Photocrosslinkable poly(vinyl alcohol) bearing styrylpyridinium groups (PVA-SbQ); Thin layer flow-cell screen-printed electrode.
Copyright © 2016. Published by Elsevier B.V.