Biosensors based on gold nanostructures

the present review discusses the latest advances in biosensor technology achieved by the assembly of biomolecules associated with gold nanoparticles in analytical devices. this review is divided in sections according to the biomolecule employed in the biosensor development: (i) immunocompounds; (ii) dna/rna and functional dna/rna; and (iii) enzymes and heme proteins. in order to facilitate the comprehension each section was subdivided according to the transduction mode. gold nanoparticles based immunosensors have a wide range of applications in food, environmental, pharmaceutical, chemistry and clinical diagnostics. the nanoparticles were employed to improve whether the analytical signal or the immunocompounds immobilization. in another section, biosensors based on dna/rna biomolecules employing gold nanostructures as labels and label-free funtional dna/rna biosensors associated to gold nanostructures as tranducers were systematically reported for rapid identification of pathogens, species of environmental interest and clinical diagnostics, respectively. the inclusion of gold nanoparticles in modified electrodes itself enhances the electron transfer between the transducer and biomolecules leading to improved bioanalytical devices when redox enzymes and heme proteins are used. biosensors for the detection and quantification of glucose and hydrogen peroxide are discussed as well.