Determination of 6-thioguanine based on localized surface plasmon resonance of gold nanoparticle

Gold nanoparticles exhibit the optical properties of localized surface plamon resonance (LSPR) and are widely applied to the biosensors. The application of gold nanoparticles to the determination of anticancer drug 6-thioguanine (6-TG) was discussed. The binding of 6-TG molecule to the surface of gold nanoparticles alters the local refractive index in the vicinity of the nanoparticles and results in a shift of the LSPR spectrum. The experimental conditions were examined and optimized. Under the optimal conditions, the ratios of absorbances at two wavelengths are directly proportional to the concentrations of 6-TG. The developed method is simple, rapid, and sensitive. In addition, this method is particularly attractive because organic cosolvents, light-sensitive dyes, and sophisticated instruments are not required. This method was successfully applied to the determination of 6-TG in real samples and the results were satisfactory. (c) 2013 Elsevier B.V. All rights reserved.