BACKGROUND:Wastewater-based epidemiology (WBE) has emerged as a transformative tool for the real-time and unbiased surveillance of community-level illicit drug consumption. The reliability of WBE depends on accurately measuring trace drugs in wastewater. Magnetic solid-phase extraction (MSPE) offers a convenient and efficient sample preparation solution. This study addresses this challenge through the development of a selective magnetic nanomaterial and its integration into an optimized analytical method, thereby enhancing the detection of amphetamine-type stimulants (ATSs) and improving WBE accuracy. RESULTS:A tailored Fe3O4@BC@PDES nanocomposite was designed and acquired from pyrolysis of pomelo peel biomass at 700 °C, and simply modified by Fe3O4 and phenylalanine-based deep eutectic solvent via Density functional theory guidance for simultaneously extracting four amphetamine-type stimulants illegal drugs. The adsorption mechanism is mainly the synergistic effect of multiple hydrogen bonding modes and π-π interactions. Subsequently, the extraction parameters of the MSPE were optimized. A method for determining trace amounts of ATSs in wastewater was established by combining ultra-high performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS). Methodological validation results indicated negligible matrix effects, a favorable linearity (R2 > 0.999), low method limits of detection (0.73-14.17 ng L-1), qualified recovery (96.4 %∼106.6 %) and good precisions (intra-day and inter-day relative standard deviations<6.9 %). Finally, the MSPE-UPLC-MS/MS method was successfully applied to real sewage samples from a sewage treatment plant, it was found that methamphetamine (MAMP) and 3,4-methylenedioxymethamphetamine (MDMA) were the main illegal drugs in the area. SIGNIFICANCE AND NOVELTY:This work presents a sensitive and reliable MSPE-UPLC-MS/MS methodology for monitoring trace illicit drugs in wastewater. The successful quantification of MAMP and MDMA in real samples confirms its practical utility. This approach strengthens wastewater-based epidemiology by enhancing objectivity and real-time capability, supporting actionable public health insights.

A significant challenge in the rational design of biochar as an adsorbent for organic pollutants lies in the accurate prediction of adsorption performance. Machine learning (ML) offered a data-driven solution to identify key biochar parameters and underlying adsorption mechanism that are difficult to capture using conventional methods. This study combined ML with density functional theory (DFT) calculations fully decoded the adsorption process of codeine onto deep eutectic solvent (DES) modified biochar. Results demonstrated that XGBoost model showed the highest prediction performance with R2 of 0.9237, RMSE of 0.3002, and MAE of 0.2222. SHAP and PDPs identified total pore volume (Vtotal) and specific surface area (SBET), and N content as key material properties. In detail, Vtotal integrated the molecular accommodation and transference of different pores ranges, and SBET modulated the abundance of active sites. N content regulated the quantity of N-containing functional groups (e.g., -NH2, -NH3+) on the biochar, thereby facilitating chemical interactions such as hydrogen bonding and electrostatic attraction. Guided by ML insights, a high-performance DES-doped biochar was successfully synthesized, achieving a notable codeine uptake capacity of 2659.69 mu g/g. Kinetics and isotherm studies indicated hybrid physico-chemical adsorption process, while thermodynamics confirmed spontaneity and endothermicity. DFT calculations revealed MEA-based DES had the best adsorption performance with a stronger binding energy (-18.8 Kcal/mol), a lowest Delta Egap (3.367 eV), and expanded negative electrostatic potential regions, due to the dual hydrogen bonding effect. This work demonstrated a data-enhanced strategy for developing functional biochar and elucidating contaminant removal mechanisms through an integrated ML-DFT framework.

Adsorbent materials effectively separated psychoactive substances from the ambient medium through adsorption, serving as a sustainable removal strategy. In this study, a novel magnetic biochar was developed using waste shrimp shells as the raw material, through hydrochloric acid activation, Fe doping, pyrolysis, and deep eutectic solvent (DES) functionalization. The prepared adsorbents (MSBC-PG, MSBC-PA, MSBC-LA) possessed a hierarchical pore structure and abundant oxygen-containing functional groups. Among them, MSBC-PG exhibited a BET surface area of 176.9 m2 g-1, a total pore volume of 0.25 cm3 g-1, and a maximum adsorption capacity for morphine of 1186.4 μg g-1. The adsorption behavior of morphine on the material was well-described by the Langmuir and pseudo-second-order kinetic models, confirming a spontaneous and endothermic process involving both chemical and physical adsorption. MSBC-PG maintained stable adsorption performance across a pH range of 4-10, exhibited minimal interference from humic acid and urea, and retained over 85 % efficiency after five regeneration cycles. Post-adsorption characterization, density functional theory (DFT) calculations, and SHAP analysis collectively revealed that the adsorption mechanism involved the synergistic effects of pore filling, hydrogen bonding, and π-π interactions, with oxygen-containing functional groups playing a decisive role. A machine learning model based on gradient boosting decision trees (R2 = 0.99) further identified oxygen content, initial concentration, and contact time as key factors governing the adsorption process. This study provided an effective strategy for designing sustainable shrimp shell-based adsorbents to remediate opioid-contaminated water bodies.

To mitigate the environmental persistence of opioid psychoactive substances, this study developed a novel multifunctional biochar adsorbent (DMSC) derived from shrimp shell waste. Through strategic structural engineering, the material was designed with high-density hydroxyl functional groups and a hierarchical micromesoporous architecture, demonstrating exceptional adsorption affinity for three prevalent opioids in the order: morphine > O6-monoacetylmorphine (O6-MAM) > codeine. Our integrated approach combined advanced computational modeling with experimental validation, where machine learning (ML) not only verified conventional experimental results but also, through data-driven analysis, revealed complex variable interactions and their nonlinear effects on adsorption performance. The XGBoost model emerged as the most accurate predictor (R-2 > 0.95), identifying initial concentration (SHAP value = 0.63) and contact time as primary positive determinants of adsorption capacity. Density functional theory (DFT) calculations elucidated the dominant role of hydrogen bonding in the adsorption mechanism, with the C-3/C6 dihydroxyl groups of morphine forming particularly strong hydrogen bonds with DMSC surface hydroxyl groups (delta ginter = 0.07, IGMH analysis). Notably, these interactions were significantly more robust than those observed with codeine and O6-MAM. This work presents a comprehensive strategy encompassing both innovative material design and predictive modeling for the effective remediation of opioid contaminants in environmental systems.

In this work, single-factor and Box-Behnken design (BBD) experiments were utilized to optimize extraction process of methcathinone through magnetic solid phase extraction (MSPE). Magnetic biochar modified with ZIF8 and deep eutectic solvent (DES) named MBCZ@DES was used as the magnetic adsorbent in the MSPE procedure. The successful preparation of adsorbent was demonstrated via various characterizations. The BBD optimization revealed excellent agreement between predicted and experimental values. The p-value of model is below 0.05, suggesting the significance of the model. Subsequently, MBCZ@DES-based MSPE coupled with liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed for detecting methcathinone in water. Method validation demonstrated satisfactory performance with a linear calibration range of 1-200 mu g/L (R2 = 0.9999), limit of detection (LOD) at 0.137 mu g/L, and quantitation accuracy reflected by recoveries of 93.83-95.31 %. Precision studies showed relative standard deviations (RSDs, n = 6) of 1.27-4.31 % for both intra-day and inter-day precision. The MSPE-LC-MS/MS method was successfully adopted to analyze actual water samples, obtaining desirable recoveries varying from 90.89 % to 98.84 %. Mechanisms exploration revealed that reaction mechanisms between MBCZ@DES and methcathinone primarily involved it-it interaction and hydrogen bonding. The insights of governing reaction mechanisms were further explored and verified by density functional theory (DFT) calculation in detail.

The abuse of amphetamine-type stimulants (ATSs) has caused irreversible harm to public safety and ecosystems. A novel polymerized deep eutectic solvent modified magnetic pomelo peel biochar (PMBC) was prepared, and the differences in adsorption of four abused amphetamine-type stimulants (ATSs: AMP, MAMP, MDA and MDMA) were due to varying hydrogen bonds quantities and strengths. PMBC showed excellent chemical reactivity to MDMA, with a maximum adsorption capacity of 926.13 mu g g(-1), which was 3.25, 2.52 and 1.15 times higher than that of AMP, MAMP and MDA, respectively. Modern spectral analysis showed that there were a series of active centers (-COOH, -NH2 and -OH) on the PMBC, which could form hydrogen bond networks with the nitrogen and oxygen functional groups of ATSs. In various chemical environments: pH level (4-11), inorganic ion and organic matter (humic acid), PMBC maintained high activity towards four ATSs. Additionally, the quantum chemical calculations revealed that the methylenedioxy bridge of ATSs can increase the active sites, and the -NH- and -NH2 groups had different hydrogen bond formation capabilities, which together resulted in the adsorption order of PMBC on the four ATSs: MDMA > MDA > MAMP > AMP. Moreover, the hydrogen-bonding binding energies of several common hydrogen-bonding types were compared, including O-HO, N-HO/O-HN and N-HN. This study laid an empirical and theoretical foundation for the efficient capture of ATSs in water and contributed to the innovative design of materials.

The social and environment effects of illicit drug abuse are a growing global concern. Wastewater-based epidemiology (WBE) has become a common monitoring tool for assessing drug consumption. In this study, mechanical carrier (MGO), skeletal framework (ZIF-67) and functional modification (DES) were together prepared a three-dimensional nanocomposite (DES/ZIF-MGO) as an adsorbent, and developed an ultrahigh performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method coupled with optimal MSPE for the determination of ultra-trace illicit drugs in wastewater. The method exhibited good linearity (R2 >= 0.9985) with low limit of detection (0.02-1.55 mu g/L) and qualified recovery (92.1-100.9 %) for four illicit drugs (AM, METH, MDMA and MC). The characterization results showed that electrostatic, hydrogen bond, and pi-pi interaction contributed to the adsorption process. The drug consumption in a city was investigated using WBE. MC was not detected in any of the wastewater samples. The detection rates of METH and MDMA were 100 % and 82 %, respectively, while AM was found in about 18 % of the wastewater samples. Thus, based on advantages of the DES/ZIF-MGO nanocomposite, the proposed method is a rapid, sensitive and reliable method for the determination of trace illicit drugs in wastewater.

Mephedrone (4-methylmethcathinone, MEPH) exhibited severe ecologic hazards and health detriments. A novel deep eutectic solvent functionalized magnetic ZIF-8/hierarchical porous carbon (DMZH) with excellent selectivity, interference resistance and recyclability, was developed for the rapid adsorption of MEPH. Initially, potential adsorption sites of MEPH were predicted. Then, pi-pi and hydrogen bonding interactions were proposed and verified from characterizations, comparative experiments and theoretical calculations. The synergistic effects of the hydrogen bonding and pi-pi interactions increased the adsorption energies from -15.26 kcal & sdot;mol(-1) to -21.83 kcal & sdot;mol(-1), enhanced the degree of pi-dissociation, enlarged the pi-pi isosurface area, extended the van der Waals surface mutual penetration distance, achieving stronger affinity and remarkable adsorption. Furthermore, offset (parallel-displaced) pi-pi stacking form existed between DMZH and MEPH. DMZH acted as the hydrogen bond donor and MEPH served as the hydrogen bond acceptor to form O-H & ctdot;O and N-H & ctdot;O hydrogen bonding interaction. Profiting from the synergistic effects, DMZH showed satisfactory adsorption for MEPH within 20 min with a maximum adsorption capacity of 3270.11 mu g center dot g(-1), displayed excellent performance in wide pH range of 5 similar to 11 and in the coexistence of multi-chemicals.

Herein, the capture and separation properties of the deep eutectic solvent-functionalized magnetic graphene oxide/ZIF-67 composite (ZMG-DES) towards amphetamine-type drugs (MDMA, MAM and AM) from water were investigated. Kinetic and isotherm models showed that the adsorption behaviors were monolayer chemisorption. Batch experiment results showed that the maximal adsorption of MDMA (933.652 μg⋅g-1) was 2.3 and 2.8 times higher than that of MAM (412.849 μg⋅g-1) and AM (328.652 μg⋅g-1), respectively, and this superiority remained consistent under varied environmental influences (pH, background ion and humic acid). Theoretical calculations and characterization analyses demonstrated the methylenedioxy group of MDMA led to the highly selective adsorption. Electrostatic potential (ESP) distribution indicated that the methylenedioxy added electron-rich areas and provided more adsorption sites. The Independent Gradient Model (IGMH) quantified the adsorption contribution of the functional groups in each system, which the contribution of the methylenedioxy reached 25.23%, significantly exceeding that of -NH- (18.80%) and benzene ring (20.76%), and proved that the H-bonds formed methylenedioxy enhanced adsorption. Furthermore, the Hirshfeld surface analysis proved that the methylenedioxy and -NH- of MDMA acted as H-bond acceptor and donor, respectively, which synergistically promoted the adsorption. The present study will help us to understand the structure-property relationship between amphetamine-type drugs and ZMG-DES.

Wastewater-based epidemiology (WBE) has become an objective and updated surveillance strategy for monitoring and estimating consumption trends of psychoactive substances (PSs) in the population. Firstly, magnetic shrimp shell biochar-based adsorbent (DZMBC) was synthesized and employed for extraction trace PSs from municipal wastewater. Proper pyrolysis temperature and increased KOH activator content favored the pore structure and surface area, thus facilitating extraction. DZMBC delivered exceptional extraction performance such as pH stability, anti-interference property, fast magnetic separation ability, reusability, and reproducibility. Then, a method based on magnetic solid-phase extraction (MSPE) followed by ultra-high-performance liquid chromatography–tandem mass spectrometry (UPLC–MS/MS) was developed, validated, and utilized for the quantitative determination of five PSs in real wastewater samples. Methodological validation results indicated a favorable linearity, low method limits of detection (1.00–4.75 ng/L), and good precisions (intra-day and inter-day relative standard deviations < 4.8

A new adsorbent(DES@ZIF@MG) was prepared by grafting deep eutectic solvents(DES) onto metal organic framework ZIF/magnetic reduced graphene oxide(MG) for the adsorption of methamphetamine. A series of structural characterization analyses (SEM, FT-IR, BET, VSM, TGA) were facilitated to explore the microscopic morphology and physicochemical properties of DES@ZIF@MG. The adsorption performances of methamphetamine onto the adsorbent were investigated by adsorption kinetics, isotherms, and adsorption effect experiments(pH, ionic strengths, and humic acid). The results showed that the adsorption of methamphetamine onto DES@ZIF@MG was consistent with the pseudo-second-order model and the Langmuir model, indicating that the adsorption process was an energetically homogeneous adsorption dominated by chemisorption. The XPS characterization illustrated that the adsorption process of methamphetamine by DES@ZIF@MG mainly involved hydrogen bonding, π-π interaction, electrostatic interaction, and chelation.

The accurate discovering and monitoring of 3,4-methylenedioxymethamphetamine (MDMA) are especially important because of its substantial toxicity and potential harm to human and the ecological systems. Three types of polymerized deep eutectic solvents functionalized magnetic biochar (MBC@poly (AA/AAC/AAm-ChCl)) were successfully synthesized to adsorb MDMA. The isotherm and kinetic data confirmed that MBC@poly (AAm-ChCl) had the strongest adsorption capacity, and the order of adsorption capacity is as follow: MBC@poly(AAm-ChCl) > MBC@poly(AA-ChCl) > MBC@poly(MAA-ChCl), which also revealed that the adsorption was heterogeneous multi-layer chemisorption. The findings of the characterizations manifested that MBC@poly(AAm-ChCl) was the optimal adsorbent owning to its higher nitrogen content, resulting in the formation of a greater number of hydrogen bonds. Due to the strong hydrogen bonding effect of C=O and -NH2 functional groups, MBC@poly(AAm-ChCl) exhibited the high selectivity towards MDMA under the coexistence of multiple chemical substances, and excellent adsorption performance over the pH range of 4-11. Urea as a hydrogen bond inhibitor further confirmed MBC@poly(AAm-ChCl) had high-density active hydrogen bonding sites. Furthermore, utilizing density functional theory (DFT) for simulating adsorption both before and after the process verified that the high selectivity of MBC@poly(AAm-ChCl) attributed to the formation of the dual-configured hydrogen bonds. This study provides support for the production of highly selective biochar for use in pretreatment during drug detection.

The efficient and selective removal of amphetamine (AMP) from water bodies is significant for environmental remediation. In this study, a novel strategy for screening deep eutectic solvent (DES) functional monomers was proposed based on density functional theory (DFT) calculations. Using magnetic GO/ZIF-67 (ZMG) as substrates, three DES-functionalized adsorbents (ZMG-BA, ZMG-FA, and ZMG-PA) were successfully synthesized. The isothermal results showed that the DES-functionalized materials introduced more adsorption sites and mainly contributed to the formation of hydrogen bonds. The order of the maximum adsorption capacity (Q(m)) was as follows: ZMG-BA (732.110 mu g.g(-1)) > ZMG-FA (636.518 mu g.g(-1)) > ZMG-PA (564.618 mu g.g(-1)) > ZMG (489.913 mu g.g(-1)). The adsorption rate of AMP on ZMG-BA was the highest (98.1%) at pH 11, which could be explained by the less protonation of -NH2 from AMP being more favorable for forming hydrogen bonds with the -COOH of ZMG-BA. The strongest affinity of the -COOH of ZMG-BA for AMP was reflected in the most hydrogen bonds and the shortest bond length. The hydrogen bonding adsorption mechanism was fully explained by experimental characterization (FT-IR, XPS) and DFT calculations. Frontier Molecular Orbital (FMO) calculations showed that ZMG-BA had the lowest HOMO-LUMO energy gap (E-gap), the highest chemical activity and the best adsorption

Development of a superior water pretreatment for monitoring the psychoactive substances in urban is requisite. Herein, a novel adsorbent with selective adsorption capacity for methamphetamine (MAMP) has been successfully designed through deep eutectic solvents (DES) as a modifier was used to regulate magnetic reduced graphene oxide/ZIF-67 (MGZ) composites. The DES, named as Choline chloride/Levulinic acid (LA), with high affinity towards MAMP, was screened by density functional theory (DFT). The DESs regulated MGZ to synthesize DES/MGZ, and the adsorption performances of diverse DES/MGZ were investigated by contrast experiment. The selective adsorption performances were investigated by selective experiment with multiple compounds. The MAMP adsorption amount of LA/MGZ was 365.96 & mu;g g-1, and enhanced 82.98% than MGZ (200.67 & mu;g g-1). The characteristic of pH-dependent occurred on the MAMP adsorption by LA/MGZ was attributed to the exfoliation of highly oxidized debris promote H-bonding and 7C-7C interactions between LA/MGZ and MAMP. Theoretical calculations in combination with characterization analyses illustrated the efficient recognition of LA toward MAMP was mainly dependent on the H-bonding interactions between carboxyl groups of LA and the -NH of MAMP, as well as the electron transfer from MAMP to levulinic acid. The proposed strategy in this work for designing DESs as a modifier to regulate the carrier materials based on DFT calculations to improve the selective adsorption ability would inspire more ideas in efficient water environmental treatment.

Exploring the structure-dependent adsorption mechanism of contaminants in wastewater is beneficial to high-efficiency adsorbents design and environmental remediation. In this study, emerging porous material of zeolitic imidazolate framework-67 (ZIF-67) has been modified by the magnetic graphene oxide-polydopamine nanohybrid (mGOP) to obtain three-dimensional ZIF-67/mGOP through an in-situ growth strategy, which was applied to adsorb 3,4-methylenedioxymethamphetamine (MDMA, "ecstasy") in wastewater. A combination of characterizations, experiments (pH, humic acid and ion strength effect) and quantum chemical calculations revealed the microscopic adsorption mechanism involves each single component, of which the hydrogen bond (O/N center dot center dot center dot H-O) and pi-pi electron donor acceptor (pi-pi EDA) interactions of mGOP endowed favourable adsorption of ZIF-67/mGOP, and mechanisms of the pore filling and Co-O chelation of ZIF-67 played synergistic effect. Such nanocomposite as a ZIFs-based adsorbent exhibited ultra-high porosity (total pore volume = 0.4033 cm(3)/g) and specific surface area (995.22 m(2)/g), revealed the heterogeneity and multilayer adsorption properties, and obtained a theoretical maximum adsorption capacity of 159.845 mu g/g which higher than that of mZIF-67 alone. Overall, this work provided an effective strategy for rationally modulate ZIFs-based composites and exploration of adsorption mechanism. (c) 2023 Elsevier B.V. All rights reserved.

Deep eutectic solvents (DESs), an innovative class of adsorbent modifiers and pore expanders, possessed millions of possible combinations that extend their application in tailor-made designs. According to the structural features of mephedrone (4-methylmethcathinone, 4MMC), a predictive virtual library comprising 20 candidates was designed to guide the screening of DESs using density functional theory (DFT). Then, three types of DESfunctionalized magnetic ZIF-8/shrimp shell biochar (DMZSCs) were successfully synthesized. Batch adsorption experiments and selectivity evaluation experiments consolidated the results of computational prediction. DMZSC-B had a maximum adsorption capacity of 3104.12 mu g g(-1) for 4MMC, and this adsorption process was spontaneous and almost irreversible, with one 4MMC molecule anchored to 1.47 receptor sites. The remarkable adsorption originated from a synergistic coordination between suitable pore size distribution and multiple adsorption sites. DMZSC-B further exhibited a stable adsorption capacity at a wide pH and selective properties for 4MMC in the coexistence of multi-chemicals. A combination of theoretical investigations, characterizations and experiments illustrated that the adsorption mechanisms were governed by pore-filling, hydrogen bonding and p- p interaction. The selective driving forces followed the sequence of p- p interaction > hydrogen bonding interaction and the proportion contribution of the three functional groups of DMZSC-B was aromatic ring > -OH > -COOH.

针对现有方法易堵、针色谱柱使用寿命短、离子源容易污染等问题,考察实验因素,建立超声辅助提取的气相色谱质谱检测方法.通过单因素实验设计和响应面优化结合的方法,对离心过程、取材量、超声时间等进行考察优化,建立了超声辅助提取的气相色谱质谱检测笔迹形成时间方法.优化后的实验方法提取效率高、操作简便、节省时间,为字迹形成时间的研究提供了参考依据.

Psychoactive substances can irreversibly harm human health and threaten ecologic environment after entering the environment. 3D hierarchically porous carbon obtained from magnetic biochar/metal–organic framework (MBC/MOF) has been successfully prepared by changing ZIF-8 and waste biomass ratio. Comprehensive characterization results before and after ketamine adsorption showed the possible adsorption mechanisms including chelation, π-π, H-bond interaction and pore filling. Batch experiments have proved chemical and physical adsorption coexist, in which chemisorption was dominant. π-π interaction and H-bond interaction were confirmed by the humic acid and pH experiments, respectively. Further analysis of Molecular Dynamics simulations indicated that the chelation was stronger than the π-π interaction and H-bond interaction. Specifically, the Zn of ZIF-8 in MBC/MOF acted as a chelating site, the π-π interaction occurred between the graphene-like structure of MBC and the benzene ring of ketamine, the hydrogen bonding interaction was found between the oxygen-rich functional groups of MBC/MOF and the oxygen atoms of ketamine (OH···O). Anion, cation, leaching and cycle experiments indicated the MBC/MOF had outstanding anti-interference ability, high reusability, excellent stability and safety. These findings will broaden the applications of metal organic framework and magnetic biochar in the field of pollutants adsorption.