Syntheses of metal oxide-gold nanocomposites for biological applications

A range of synthetic approaches for metal oxide-gold nanocomposites from conventional method such as chemical vapor deposition (CVD), pulse laser ablation to more simple and facile synthetic approaches using mild condition have been discussed. These nanocomposites have found diverse potential biological applications including cell imaging, photothermal therapy, chemotherapy, radiotherapy, determining oxidative stress in tumor cells, glucose oxidation, enzyme mimic activity, nitrogen fixation and diagnosis purpose such as detecting cancer biomarkers such as prostate protein antigen (PSA), alpha fetoprotein (AFP), melanoma adhesion molecule antigen (CD146), DNA sensing. The biosensing applications along with quantitative estimation of bioanalytes such as choline (CHO), NADH, epinephrine (EP), 17 beta-estradiol (E2), uric acid (UA), ascorbic acid (AA), glucose and dopamine, alpha-synuclein, amyloid beta (A beta) peptide, glutathione (GSH), calcium dipicolinate have been explored with these nanocomposites as platforms. Abnormal levels of hydrazine (principal component of various pharmaceutical derivative), Cr(VI), tertracyclin (broad spectrum antibiotic), 6-mercaptopurine (anticancer drug), Bisphenol A (BPA), chlorpyrifos and carbamate pesticides have been estimated with these metal oxide-gold nanocomposites. Various detection strategies for quantitative analysis based on electrochemical, fluoro-metric and colorimetric methods have been briefly summarized.