Increasing amperometric biosensor sensitivity by length fractionated single-walled carbon nanotubes.

Research output: Contribution to journalArticle

Abstract

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.

Details

Authors
  • Federico Tasca
  • Lo Gorton
  • Jakob Wagner
  • Gilbert Nöll
Organisations
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Analytical Chemistry
  • Chemical Sciences

Keywords

  • Amperometric biosensor, Diaphorase, NADH oxidation, Osmium redox polymer hydrogel, Length-separated single-walled carbon nanotubes (SWCNTs), Transmission electron microscopy (TEM)
Original languageEnglish
Pages (from-to)272-278
JournalBiosensors & Bioelectronics
Volume24
Issue number2
Publication statusPublished - 2008
Publication categoryResearch
Peer-reviewedYes

Bibliographic note

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)