Self-assembled Monolayers for Biosensors

Abstract

The use of self-assembled monolayers (SAMs) in various fields of research is rapidly growing. In particular, many biomedical fields apply SAMs as an interface-layer between a metal surface and a solution or vapour. This review summarises methods for the formation of SAMs upon the most commonly used materials and techniques used for monolayer characterisation. Emphasis will lie on uniform, mixed and functionalised monolayers applied for immobilisation of biological components including (oligo-)nucleotides, proteins, antibodies and receptors as well as polymers. The application of SAMs in today's research, together with some applications will be discussed.

Carbon and gold electrodes as electrochemical transducers for DNA hybridisation sensors

“…Self-assembly provide one of the most elegant approaches to obtain well defined and organised surfaces that can be an excellent platform for biosensor applications. General features of self-assembled monolayers (SAMs) onto gold surfaces have been summarised in several papers and reviews (Chidsey and Loiacono, 1990;Wink et al, 1997;Chaki and Vijayamohanan, 2002) and have been briefly covered in the following section. Even more elegant approaches involve the direct chemisorption of thiol-modified DNA probes onto gold surfaces.…”

“…An uncontaminated gold surface is important but not essential for the chemisorption; the high affinity of the thiol moiety for gold even displaces contaminants (Wink et al, 1997). Nevertheless, as a precaution, gold disk electrodes are, usually, mechanically polished with alumina, sonicated and etched in acidic or alkaline solutions to remove possible contaminants.…”

Self-assembled Monolayers of Two Aromatic Disulfides and a Diselenide on Polycrystalline Silver Films: An Investigation by SERS and XPS

“…Organic molecular films in general and SAMs in particular can have a wide variety of applications in the fields of chemical sensors (2), nonlinear optical materials, photo patterning methodology (3), etc. Following the early reports of Allara and Nuzzo (4) on the adsorption of organic thiols on gold, various aliphatic thiols were studied (5).…”

Imunossensor amperométrico

“…Portanto, ao propiciar a imobilização pela fração Fc, permite-se uma orientação adequada do anticorpo imobilizado obtendo-se sítios ligantes direcionados para a solução contendo a amostra ou padrão. O uso de proteínas que orientem a imobilização dos anticorpos, como a proteína A 15 e proteína G 16 , a imobilização através de monocamadas formadas pelo método Langmuir-Blodgett 18 ou via tiocompostos 18 são os ideais sob o ponto de vista do acesso do antígeno para a reação de afinidade.…”