A molecular imprinted polymer based sensor for measuring phosphate in wastewater samples

Phosphate detection in water samples is still completed using colorimetric standard methods, which have a number of disadvantages, to such as being time consuming, requiring filtration, a number of different reagents, frequent calibration and proper disposal of waste chemicals generated. Hence, a simple cost effective analytical method and instrumentation is highly desirable to aid the optimisation of treatment processes and assist the water industry in their efforts to comply with stringent regulations such as the EU's Water Framework Directive. A sensor based on molecular imprinted polymer (MIP) and a conductance transducer was developed for direct and label-free detection of phosphate in water. The sensor was able to measure the presence of phosphate in wastewater samples with good reproducibility, a linear range of 0.66-8 mg P L(-1) and a lower detection limit of 0.16 mg P L(-1). The sensor was further tested to measure phosphate concentrations in unfiltered field samples such as domestic wastewater treatment influent and river water and demonstrated a close correlation with reference measurements. The phosphate MIP sensor offers a way forward as either a handheld sensor for use in the field, or as a potential solution for remote, continuous monitoring of phosphate.