Gold colloids and electrochemical detection: Interest in immunoassays and molecular biology [Les colloïdes d'or et leur détection électrochimique: Intérêt en immunoanalyse et en biologie moléculaire]
Résumé
Metal nanoparticles have attracted broad recent attention as labels for biotechnological systems. Recently, we reported a novel sensitive affinity assay (immunoassay, hybridization test) using colloïdal gold label that was determined by electrochemistry at carbon-based screen-printed electrode (SPE). The high performance of the method is related both to the release of a large number of gold from each nanoparticle anchored in the bioaffinity complex (e.g. ≅2.5 × 105 gold atoms are theoretically contained in a 20-nm spherical gold nanoparticle) and to the sensitive electrochemical method based on the use of microband electrodes. We present here two applications of this approach: a sandwich immunoassay of α-fetoprotein (AFP) and an hybridization test for the detection of human amplified cytomegalovirus DNA (HCMV DNA) fragment which offer great promise for the development of an electrochemical biosensor technology. © 2004 Elsevier SAS. Tous droits réservés.