Electromimetic molecularly imprinted Polymersensor for wastewater emtricitabine

• Published in: Analytica chimica acta 2024-11, Vol.1329, p.343184, Article 343184
• Main Authors: Mokwebo, Kefilwe V., Douman, Samantha F., Januarie, Kaylin C., Oranzie, Marlon, Sanga, Nelia A., Leve, Zandile D., Cox, Meleskow, Ross, Natasha, Iwuoha, Emmanuel I.
• Format: Article
• Language: English
• Subjects: Electrochemical sensors; Electrochemical Techniques - methods; Electrodes; Electropolymerization; Emerging micropollutants; Emtricitabine; Emtricitabine - analysis; Limit of Detection; Magnetite Nanoparticles - chemistry; Molecular Imprinting; Molecularly imprinted polymer; Molecularly Imprinted Polymers - chemistry; Wastewater; Wastewater - analysis; Wastewater - chemistry; Water Pollutants, Chemical - analysis
• ISSN: 0003-2670; 1873-4324; 1873-4324
• DOI: 10.1016/j.aca.2024.343184

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. Herein, a molecularly imprinted poly(para-aminobenzoic acid) (MIP) was electrochemically prepared on iron oxide nanoparticles modified glassy carbon electrode (MIP/Fe3O4 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−1 and a limit of detection (LOD) and limit of quantification (LOQ) of 0.439 and 1.30 μg L−1, 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-Fe3O4/GCE-based sensor achieved recoveries of 98.8 %–101.5 % for applications in real wastewater and drinking water samples. The combination of Fe3O4 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. [Display omitted] •Preparation of MIP/Fe3O4 NPs/GCE sensor for micropollutant, emtricitabine (FTC).•Utilization of Langmuir-Freundlich adsorption isotherm for FTC-MIP sensor binding.•Sensor demonstrates high sensitivity with LOD and LOQ of 0.439 and 1.30 μg L−1.•Application of MIP sensor in real water samples showed 98.8 %–101.5 %.