Nanomaterial strategies for immunodetection

Abstract

Metallic nanoparticles are playing increasingly important roles in biodiagnostic platforms. This emergence reflects the need to detect disease indicating entities at increasingly lower levels in human and veterinary diagnostics, homeland security, and food and water safety. To establish this perspective, this paper overviews our recent work using surface enhanced Raman scattering for detection of proteins, viruses, and microorganisms in heterogeneous immunoassays. It describes the assay platform, which is comprised of an antibody-modified capture substrate and gold nanoparticle-based label. The latter draws on the ability to reproducibly construct gold nanoparticles modified with a monolayer of an intrinsically strong Raman scatterer that is then coated with a layer of antibodies. This construct, referred to as an extrinsic Raman label, takes advantage of the signal enhancement of scatterers when coated on nanometer-sized gold particles and the antigenic binding specificity of the immobilized antibody layer. Challenges related to nonspecific adsorption, particle stability, and measurement reproducibility are also briefly examined.

Ultrasensitive Detection of Hepatotoxic Microcystin Production from Cyanobacteria Using Surface-Enhanced Raman Scattering Immunosensor

“…SERS exploits the localized surface plasmon resonance (LSPR) to amplify the Raman signal of specimen in the vicinity of plasmonic substrates (e.g., Au, Ag) with an enhancement factor of up to 10 14 . [12][13][14][15] Due to the advantages such as simplicity, photostability, quantifiability and multiplexing capability, SERS is emerging as an analytical method in applications ranging from biomedical imaging to chemical sensing. 12,13,[16][17][18][19] Few studies have exemplified the success of Raman spectroscopy 20 or SERS techniques 21 for detection of MC-LR in aquatic settings with superior performance in terms of excellent specificity or high sensitivity.…”