Label-Free Silver Nanoparticles for the Determination of Gentamicin.

A new spectrophotometric method for the determination of gentamicin has been developed. The method is based on the aggregation of label-free silver nanoparticles leading to change in absorption spectra and color of the solution. Influence of different factors on the aggregation and analytical performance of the method were investigated. Results showed that the absorption ratio in 510 nm and 394 nm of silver nanoparticles was liner with gentamicin concentration in human urine samples in the range of 0.2-4.5 mu g/mL and the detection limit was calculated to be 0.16 mu g/mL. The proposed method is a promising mean for the detection of gentamicin in human urine, with the recovery between 97% and 103%. Compared with the reported methods for the determination of gentamicin, the method established in this paper is simple, rapid, cost-effective, intuitive and sensitive.