Sensitive biosensing strategy based on functional nanomaterials

Abstract

The first decade of the 21st century has been labeled as "the sensing decade". The functional nanomaterials offer excellent platforms for fabrication of sensitive biosensing devices, including optical and electronic biosensors. A lot of works have focused on the biofunctionalization of different nanomaterials, such as metal nanoparticles, semiconductor nanoparticles and carbon nanostructures, by physical adsorption, electrostatic binding, specific recognition or covalent coupling. These biofunctionalized nanomaterials can be used as catalysts, electronic conductors, optical emitters, carriers or tracers to obtain the amplified detection signal and the stabilized recognition probes or biosensing interface. The designed signal amplification strategies have greatly promoted the development of stable, specific, selective and sensitive biosensors in different fields. This review introduces some novel principles and detection strategies in the area of biosensing, based on functional nanomaterials. The general methods for biofunctionalization of nanomaterials with biomolecules and their biosensing application in immunoassay of protein, DNA detection, carbohydrate analysis and cytosensing are also described.

Voltammetric Immunoassay for the Detection of Protein Biomarkers

“…Our work has developed a generic platform for a fast and sensitive electrochemical immunoassay, building on the routes of covalent attachment of the platform to the electrode surface 45–50 and its subsequent derivitisation via attachment of a protein, and have demonstrated its operation for detecting the heart disease biomarker creatine kinase, and the tumour biomarker IL10 in physiological buffers, as well as the measurement of creatine kinase in animal heart tissue samples. Unlike other similar work in this field 62–64, our system operates with a very short molecular wire between the redox‐tagged protein and the electrode surface; we beleive this to be important for the good sensitivity of the developed protocols, since the length and nature of the linker can limit the rate of electron transfer within molecular wires 57. We believe that this sensing system is entirely suitable for assessment of many factors in ex vivo perfusion studies employing microfluidic systems 11, which require both high sensitivity and rapid measurement, the two most desired parameters for portable, early diagnosis and point‐of‐care devices.…”

Signal Amplification for Highly Sensitive Immunosensing

“…However, owing to the inherent background signals of various instrumental analytical technologies and the limitation of the classical analytical methodologies, improving the sensitivities via traditional physical methods or simple chemical and biocatalytic processes is far from meeting the practical demands. The progress in nanotechnology and biotechnology sets a convenient and promising way for design of signal amplification strategies [1][2][3], which leads to novel immunoassay methods with high sensitivity.…”

A sensitive electrochemiluminescence cytosensor for quantitative evaluation of epidermal growth factor receptor expressed on cell surfaces

“…It is attracted considerable interest and has been widely used in immunoassay [8,9], DNA analysis [10], clinical diagnosis [9,11], carbohydrate analysis [12] and cytosensing [11,13]. Although Han et al [14] have used ECL technique monitor the cell-surface carbohydrate expression [15]. However, there have been few reports concerning detecting and dynamically tracing the changes of EGFR expression level on cell surfaces by ECL cytosensor.…”