Determination of human urinary kanamycin in one step using urea-enhanced surface plasmon resonance light-scattering of gold nanoparticles

The purpose of this study was to establish a simple, sensitive analytical method for kanamycin (KANA) in human urine. Enhancement of the plasmon resonance light-scattering (PRLS) of gold nanoparticles (AuNPs) by KANA provided the basis for this analytical method. At pH 6.7, KANA induced AuNPs aggregation with enhanced PRLS. The PRLS of the AuNPs-KANA system was further enhanced by addition of urea. The linear range and detection limit for KANA were from 20-800 nmol L-1 and 2 nmol L-1, respectively. Potential interfering substances present in urine had a negligible effect on the determination, thus preliminary sample separations were not necessary. Recovery of KANA from spiked human urine was 94-104%. This simple, sensitive method, using urea to enhance the PRLS of the AuNPs-KANA system, may provide a new approach for determination of compounds rich in OH groups.