1.Department of Physics and Nanotechnology,SRM University,Kattankulathur,India;2.Department of Chemistry,Kalasalingam University (Kalasalingam Academy of Research and Education),Krishnankoil,India;3.Electrochemical Materials Science and Functional Materials Division,CSIR-Central Electrochemical Research Institute,Karaikudi,India
Abstract:
Gold nanorods (AuNRs) show high potential in electrochemical sensing owing to their excellent conductivity, electrocatalytic activity, selectivity and sensitivity. This review (with 99 refs.) summarizes the performance of AuNR-based electrochemical sensors based on the use of advanced nanocomposites. Following an introduction into the fields of biosensors and nanomaterials, the article summarizes the advantages and limitations of conventional analytical methods. A third section overviews the methods for preparation and characterization of AuNRs and nanocomposites including bimetallic nanorods, gold-metal oxide, gold-carbon nanotubes, gold-polymer, gold-graphene, gold-CNT and gold-enzymes conjugates. Their electrochemistry is treated next, with aspects related to the effects of rod size and shape, of thiol coatings on voltammetric signals, and on the behavior of 1-D AuNRs and respective arrays. Section 5 gives examples for non-enzymatic sensors for simple biomolecules, with subsections on sensors for hydrogen peroxide, nitric oxide, glucose, dopamine, NAD/NADH, cysteine, and some drugs. Section 6 covers enzyme-based sensors, with examples on sensors using peroxidases, oxidases and the like. The next sections cover DNA biosensors (such as for DNA biomarkers) and immunosensors, mainly for tumor markers. Possibilities for improving sensor performance are presented at the end of the review.
