Increasing amperometric biosensor sensitivity by length fractionated single-walled carbon nanotubes.
Research output: Contribution to journal › Article
In this work the sensitivity-increasing effect of single-walled carbon nanotubes (SWCNTs) in amperometric biosensors, depending on their average length distribution, was studied. For this purpose the SWCNTs were oxidatively shortened and subsequently length separated by size exclusion chromatography. Transmission electron micrographs of different fractions of SWCNTs were collected. Diaphorase "wired" to an osmium redox polymer was blended with the shortened SWCNTs of different lengths. Depending on the average length of the SWCNTs the sensitivity of the amperometric biosensor model system towards oxidation of 1,4-dihydronicotinamide adenine dinucleotide (NADH) was increased by a factor of five. The best performance was achieved with SWCNTs of medium length. The linear range for NADH detection was between 5muM and 7mM, the maximum sensitivity was 47nAmuM(-1)cm(-2), and the detection limit was 1muM. The biosensor exhibited excellent electrocatalytic properties. Even at relatively high NADH concentrations the oxidative current was limited by the diffusion rate of NADH.
|Research areas and keywords||
Subject classification (UKÄ) – MANDATORY
|Journal||Biosensors & Bioelectronics|
|Publication status||Published - 2008|
The information about affiliations in this record was updated in December 2015. The record was previously connected to the following departments: Analytical Chemistry (S/LTH) (011001004), Polymer and Materials Chemistry (LTH) (011001041)