Enzyme/semiconductor nanoclusters combined systems for novel amperometric biosensors

W. Vastarella, R. Nicastri

Research output: Contribution to journalArticle

78 Citations (Scopus)


In this work quantum-sized CdS nanocrystals were synthesized using a quaternary water-in-oil microemulsion and immobilized onto gold working electrode by self-assembled monolayers techniques. Formaldehyde dehydrogenase was covalently immobilized onto a protecting membrane, which was stratified on part of the semiconductor nanoparticles modified electrode. The covalent enzyme immobilization has been required to improve the stability of the catalytic oxidation of formaldehyde, which occurs after light stimulation of the semiconductor through the electron/hole recombination. A study about the best electrochemical oxidation potentials under different flow conditions was performed. Preliminary sensor stability and interferences tests were also carried out, for a sensitive and selective detection of formaldehyde. A detection limit of 41 ppb of formaldehyde was calculated and an operational stability of 6 h was achieved under flow conditions by means of this novel amperometric biosensor based on FDH-semiconductor hybrid systems, not requiring NAD+/NADH as charge transfer in the enzymatic reaction. © 2004 Elsevier B.V. All rights reserved.
Original languageEnglish
Pages (from-to)627 - 633
Number of pages7
Issue number3
Publication statusPublished - 30 Apr 2005
Externally publishedYes


All Science Journal Classification (ASJC) codes

  • Chemistry(all)

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