Optimisation of immuno-gold nanoparticle complexes for antigen detection

Van Der Heide, Susan and Russell, David (2016) Optimisation of immuno-gold nanoparticle complexes for antigen detection. Journal of Colloid and Interface Science, 471. pp. 127-135. ISSN 0021-9797

[thumbnail of AuNP comparison paper_revision] Microsoft Word (AuNP comparison paper_revision) - Accepted Version
Available under License Creative Commons Attribution Non-commercial No Derivatives.

Download (1MB)

Abstract

The aim of this investigation was to define the optimum method of binding antibodies to the surface of gold nanoparticles (AuNPs) and then to apply the optimised antibody-functionalised AuNPs for the detection of a target antigen. A detailed investigation of three different techniques for the functionalisation of AuNPs with anti-cocaine antibody and methods for the subsequent characterisation of the antibody-functionalised AuNP are reported. The addition of anti-cocaine antibody onto the AuNP surface was facilitated by either: a polyethylene glycol (PEG) linker with a –COOH terminal functional group; an aminated PEG ligand; or an N-succinimidyl 3-(2-pyridyldithio)-propionate (SPDP)-Protein A/G intermediate. Characterisation of the functionalised particles was performed using transmission electron microscopy, UV-Visible spectrophotometry and by agarose gel electrophoresis. In addition, the cocaine binding efficacy of the resultant AuNPs and their cocaine-binding capacity was determined using a cocaine-horseradish peroxidase conjugate, and by the application of a microtiter plate-based immunoassay. The results showed that the number of antibody per particle was the highest when the AuNP were functionalised with the Protein A/G intermediate. As compared to free antibody, the cocaine binding efficacy was significantly enhanced using the AuNP-Protein A/G-antibody complex. This optimal antibody-antigen binding efficacy is thought to be the result of the large number of antibody per particle and the oriented binding of the antibody to the Protein A/G on the AuNP surface. These results highlight the ideal immuno-gold nanoparticle characteristics for the detection of target antigens such as cocaine.

Item Type: Article
Uncontrolled Keywords: gold nanoparticles,antibodies,conjugation,cocaine
Faculty \ School: Faculty of Science > School of Chemistry
UEA Research Groups: Faculty of Science > Research Groups > Physical and Analytical Chemistry (former - to 2017)
Depositing User: Pure Connector
Date Deposited: 22 Mar 2016 09:37
Last Modified: 22 Oct 2022 00:54
URI: https://ueaeprints.uea.ac.uk/id/eprint/57823
DOI: 10.1016/j.jcis.2016.03.001

Actions (login required)

View Item View Item