Chapter 8 - Biofabrication of graphene QDs as a fluorescent nanosensor for detection of toxic and heavy metals in biological and environmental samples

Abstract

Heavy metal contamination in the environmental samples is one of the major concerns to human health because of their highly toxicity and retention in the ecological system. The exposure to heavy metal ions such as lead, mercury, uranium, and cadmium causes neurological disorders, cancer mortality, cardiovascular diseases, and damage to liver and kidney. To overcome this, it is required to analyze heavy metal ions in environmental samples by fast and reliable methods. Nowadays, optical detection techniques are more convenient over the electrochemical techniques, such as voltammetric and potentiometric techniques, due to their simplicity and low-detection limits. Therefore, graphene quantum dots (GQDs) are promising a fast, sensitive, and selective fluorescent sensor probe for determination of toxic heavy metal ions. GQDs have gained importance due to its biocompatibility, low cytotoxicity, fluorescence, facile surface functionalization, and highly dispersibility in water. The capability of metal ion sensing makes the GQDs as fluorescent probe in detection of various toxic heavy metal ions in environmental and biological samples with high selectivity.