Nanomaterial-based strategies for enhanced mercury trace analysis in environmental and drinking waters

This review presents analytical strategies for mercury trace analysis in environmental and drinking water samples by the application of nanomaterials (NMs). The methods are subsequently classified into two groups: (A) approaches aiming to substitute elaborate sample pretreatment, separation and pre-concentration procedures by simplified procedures and (B) approaches providing enhanced detection techniques with regard to fast signal read-out, miniaturised instrumentation and, simultaneously, high sensitivity. Therefore, the review includes NM-based sample preparation as well as optical and electrochemical detection techniques. Their applicability for monitoring purpose is discussed by evaluating sensitivity and selectivity considering real-water matrices as well as by assessing the simplicity and duration of the analysis. A selection of examples published within the last 3 years is presented in Table 2, Table 3. These are sorted into methods allowing for monitoring of the permissible Hg levels in drinking water (limit of detection, LOD <10 nM) and those capable of detecting ultra-trace levels of mercury in pristine environmental waters (LOD < 0.05 nM).