A simple method for detection of anionic detergents in milk using unmodified gold nanoparticles

Economically Motivated Adulteration (EMA) incidences of milk and infant milk formula by hazardous chemicals like urea, detergent and melamine have increased recently. Since milk and milk products are consumed by infants, adults and geriatric population alike, such adulterations need to be tackled on priority. In the present study, we report a novel approach to detect anionic detergents (ADs) in milk by exploiting the optical and spectral properties of gold nanoparticles (AuNPs). The developed method is specific for AD detection and is free from interference of other adulterants. The limit of detection for ADs like sodium dodecylbenzenesulfonate (SDBS) and commercial ADs in milk was 23 and 92 μg/ml, respectively.