Starch based nanocomposites as sensors for heavy metals - detection of Cu2+ and Pb2+ ions

Inorganic nanocomposites can find application in various branches of industry, including food technology. Quantum dots have already been reported as promising nanosensors for the detection of heavy metal ions in soil, water and food. This study presents novel starch-based nanocomposites containing ZnS quantum dots capped with L-cysteine. The nanocomposites were prepared in form of gels and foils of potato starch with embedded spherical quantum dots sized 10-20 nm. They were characterized using photoluminescence, IR and UV spectra and TEM/SEM photographs. Pb2+ and Cu2+ ions decreased emission intensity of the photoluminescent spectral bands. The described quantum dots have been obtained using a simple, safe and low-cost method. Their properties make them alternative sensors for Pb2+ and Cu2+ ions that could be applied in biotechnology and food technology.