%0 Journal Article
%T Development and Electrochemical Investigations of an EIS- (Electrolyte-Insulator-Semiconductor) based Biosensor for Cyanide Detection
%A Monika Turek
%A Lothar Ketterer
%A Melanie Cla£¿en
%A Heinz K. Berndt
%A Gereon Elbers
%A Peter Kr¨¹ger
%A Michael Keusgen
%A Michael J. Sch£¿ning
%J Sensors
%D 2007
%I MDPI AG
%R 10.3390/s7081415
%X A cyanide biosensor based on a pH-sensitive p-doped electrolyte-insulator-semiconductor (EIS) structure with an immobilised enzyme (cyanidase) is realised at thelaboratory scale. The immobilisation of the cyanidase is performed in two distinct steps:first, the covalent coupling of cyanidase to an N-hydroxysuccinimide- (NHS) activatedSepharoseTM gel and then, the physical entrapment of NHS-activated SepharoseTM with theimmobilised cyanidase in a dialysis membrane onto the EIS structure. The immobilisationof the cyanidase to the NHS-activated SepharoseTM is studied by means of gelelectrophoresis measurements and investigations using an ammonia- (NH3) selectiveelectrode. For the electrochemical characterisation of the cyanide biosensor,capacitance/voltage and constant capacitance measurements, respectively, have beencarried out. A differential measurement procedure is presented to evaluate the cyanideconcentration-dependent biosensor signals.
%K cyanide biosensor
%K EIS structure
%K cyanidase
%K pH
%K differential measurement set- up.
%U http://www.mdpi.com/1424-8220/7/8/1415