Detection and remediation of chiral pharmaceuticals from wastewater: A review

For the occurrence of PPCPs from source to tap: A novel approach modified in terms of sample preservation and SPE cartridge to monitor PPCPs in our water supply

BACKGROUND

The ongoing infusion of pharmaceutical and personal care products (PPCPs) into ecosystems sustains a perpetual life cycle and leads to multi-generational exposures. Limited understanding of their environmental impact and their intrinsic ability to induce physiological effect in humans, even at low doses, pose great risks to human health. Few scholarly works have conducted systematic research into the occurrence of PPCPs within potable water systems. Concurrently, the associated monitoring techniques have not been comprehensively examined with regards to the specific nature of drinking water, namely whether the significant presence of disinfectants may influence the detection of PPCPs.

RESULTS

A modified approach in terms of detailed investigation of sample preservation and optimization of an in-lab fabricated solid phase extraction (SPE) cartridge filled with DVB-VP and PS-DVB sorbent was proposed. Favorable methodological parameters were achieved, with correlation coefficients spanning from 0.9866 to 0.9998. The LODs of the PPCPs fluctuated from 0.001 to 2 μg L-1, while the LOQs varied from 0.002 to 5 μg L-1. The analysis of spiked samples disclosed a methodological precision of 2.31-9.86 % and a recovery of 52.4-119 %. We utilized the established method for analyzing 14 water samples of three categories (source water, finished water and tap water) from five centralized water supply plants. A total of 24 categories encompassing 72 PPCPs were detected, with the concentrations of PPCPs manifested a marked decrease from source water to finished water and finally to tap water.

SIGNIFICANCE

Our research meticulously examined the enhancement and purification effects of widely used commercial SPE cartridges and suggested the use of in-lab fabricated SPE cartridges packed with DVB-VP and PS-DVB adsorbents. We also conducted a systematic evaluation of the need to incorporate ascorbic acid and sodium thiosulfate as preservatives for PPCP measurement, in consideration of the unique characteristics of drinking water matrices, specifically, the significant concentration levels of disinfectants. Furthermore, the proposed method was effectively employed to study the presence of PPCPs in source water, finished water, and tap water collected from centralized water supply plants.

Stereoselective analysis of chiral pesticides: a review

Chiral organic pollutants, including pesticides, herbicides, medicines, flame retardants, and polycyclic musk, represent a significant threat to both the environment and human health. The presence of asymmetric centers in the structure of chiral pesticides introduces stereoisomers with distinct distributions, fates, biomagnification capacities, and cytotoxicities. In aquatic environments, pesticides, as persistent/pseudo-persistent compounds, have been detected in substantial quantities, posing severe risks to non-target species and, ultimately, public health through water supply and food exposures. In response to this environmental challenge, stereoselective analytical methods have gained prominence for the identification of pesticide/drug enantiomers in recent years. This review examines the environmental impact of chiral pesticides, emphasizing the distinct biological activities and distribution patterns of their stereoisomers. By highlighting the advancements in liquid chromatography for enantiomeric analysis, the review aims to underscore the urgent need for a comprehensive understanding of these pollutants to facilitate informed remediation strategies and ensure the safer dispersal of chiral organic pollutants in the environment, thereby addressing the potential risks they pose to ecosystems and human health. Future research should focus on developing sustainable and efficient methodologies for the precise analysis of stereoisomers in complex matrices, particularly in sewage water, emphasizing the importance of sewage processing plants in ensuring water quality.

Fabrication of a bifunctional fluorescent chiral composite based on magnetic Fe3O4/chiral carbon dots@hierarchical porous metal-organic framework

Considering the selective pharmacological activity and ecotoxicity of chiral drugs, the development of chiral materials with the dual functions of enantiomeric recognition and adsorption is of great significance. Herein, a novel bifunctional chiral composite (Fe3O4/CCDs@HP-ZIF-8) which does not contain expensive and rare fluorescent chiral ligands or metal ions, was constructed for the first time by encapsulating chiral carbon dots (CCDs) and magnetic Fe3O4 nanoparticles into hierarchical porous metal-organic frameworks (HP-MOFs). Fe3O4/CCDs@HP-ZIF-8, which integrates fluorescent chiral property, magnetism, and hierarchical porosity, shows enormous potential in enantiomeric recognition and adsorption. Fluorescence detection results demonstrate that Fe3O4/CCDs@HP-ZIF-8 presents different fluorescence quenching for naproxen enantiomers. The limits of detection are determined to be 0.05 μM for S-naproxen (S-Nap) and 0.30 μM for R-naproxen (R-Nap), respectively. Furthermore, the isothermal, kinetic, and thermodynamic adsorption behaviors of Fe3O4/CCDs@HP-ZIF-8 to naproxen enantiomers were systematically studied. Due to its hierarchical porosity, the composite exhibits higher adsorption capacity to naproxen enantiomers compared to the non-hierarchical porous composite. Studies of enantiomeric recognition and adsorption mechanisms affirm that the synergistic effect of multiple mechanisms exists between Fe3O4/CCDs@HP-ZIF-8 and naproxen enantiomers. Finally, the satisfactory recoveries and relative standard deviations in the actual sample assays demonstrate the practicality of Fe3O4/CCDs@HP-ZIF-8 for S-Nap detection. This non-destructive functionalization method creates an innovative pathway for developing advanced multifunctional chiral materials, holding great promise for enantiomeric recognition and adsorption.