Electromimetic molecularly imprinted Polymersensor for wastewater emtricitabine.

BACKGROUND

Emtricitabine (FTC) is a commonly prescribed anti-human immunodeficiency virus (HIV) drug that has been classified as an emerging environmental pharmaceutical micropollutant due to its poor metabolism, refractory nature to wastewater treatment, continuous discharge with wastewater effluent and accumulation in the aquatic environment. Although there are no reported limits and toxicity of the drug in the environment yet, it is crucial to develop onsite, rapid, selective and ultrasensitive water sensing systems for FTC to ensure efficient risk management and environmental sustainability.

RESULTS

Herein, a molecularly imprinted poly(para-aminobenzoic acid) (MIP) was electrochemically prepared on iron oxide nanoparticles modified glassy carbon electrode (MIP/FeO NPs/GCE) for selective detection of FTC using differential pulse voltammetry (DPV) and electrochemical impedance spectroscopy (EIS). During the detection, the voltammetric signal of the MIP sensor decreased with increasing concentrations of the non-electroactive FTC, indicating hindrance of the MIP sensor's redox activity by the binding analyte. The sensor generated a calibration curve with a linear dynamic range of 1.24-24.7 μg L and a limit of detection (LOD) and limit of quantification (LOQ) of 0.439 and 1.30 μg L, respectively. Moreover, the MIP sensor was 5.2 times more sensitive than the control sensor, a non-imprinted polymer (NIP) sensor, and had a higher apparent binding affinity for FTC than the NIP sensor. The MIP/PABA-FeO/GCE-based sensor achieved recoveries of 98.8 %-101.5 % for applications in real wastewater and drinking water samples.

SIGNIFICANCE

The combination of FeO nanoparticles, electrically conducting polymer, and the MIP technology produced a novel, simple, cost-effective, and high-performance voltammetric MIP sensor for an anti-HIV drug, FTC. The result of this study shows that the sensor holds a significant promise for future onsite monitoring of emtricitabine in wastewater, pharmaceutical, and biological samples without prior sample pretreatment.