Ultrasensitive detection and removal of carbamazepine in wastewater using UCNPs functionalized with thin-shell MIPs

Abstract

One of the issues that are currently emerging is the occurrence of pharmaceutical compounds including carbamazepine (CBZ) in environmental wastewater. We have developed upconversion particles (UCNPs@MIP) coated with new molecular imprinted polymer (thicknesses of 2.2 and 3 nm) through in situ photopolymerization by the internal green light of UCNPs upon photoexcitation at 980 nm. It has been utilized for ultrasensitive detection through fluorescence quenching of UCNPs emission by CBZ. The detection limits for CBZ with two different UCNPs@MIP were 28.5 and 40.0 pM (S/N = 3) with wide linear ranges and good correlation coefficients. Furthermore, the practical application of the sensors for the CBZ determination in wastewater and serum matrix was successfully investigated with acceptable recoveries of 98.2–104.2% and RSD less than 5%. Interestingly, the synthesized UCNPs@MIP revealed high selectivity with imprinting factors of 12.85 and 10.24 for MIP-a and MIP-b, respectively. Remarkably, UCNPs@MIP could be also blended with chitosan to form CS-MIP composite film as a simple removal technique of CBZ from wastewater samples with an adsorption capacity of 2.23 mg g−1 and removal percentage of 99.7% after 18 h. This method offers a novel facile strategy to develop UCNPs@MIP sensors for selective, sensitive, and accurate sensing of CBZ in environmental wastewater and biological samples.