Background: Photonic crystals (PC) change light’s phase and angle through periodic refractive index structures. PC with Dense Wavelength Division Multiplexing (DWDM) are used as filters, multiplexers, and demultiplexers. The existing optical sensing system has drawbacks for sensing ethanol in the liquid phase, including limited tunability, selectivity, and integration. Methods: A T-Shaped Photonic Crystal Narrowband Filter (TS-Phc)-based sensor is proposed with a two-dimensional square-lattice photonic crystal structure. The TS-Phc sensor has air holes with a radius of 0.112 μm, etched in silica with a lattice constant of 550 nm, on a 13 × 12 μm wafer. A line defect is introduced to form bus and drop waveguides in a T-shaped configuration. Point defects are added to improve selectivity. The design was optimized using the two-dimensional Finite-Difference Time-Domain (FDTD) method. A narrowband filter is used in TS-Phc for liquid ethanol concentration detection using DWDM. A Near-infrared (NIR) diode (OD-800L) is used as a light source. The OD-800L near-infrared diode is used as an independent proof-of-concept illumination source for optical signal acquisition and preprocessing studies. The 800 nm source does not directly excite the 1541–1556 nm photonic resonance mode. The optical signal passing through a liquid ethanol sample in a test tube and the photonic sensor was acquired by an APT 0800-3111-111 detector through the DAQ system. Detector signals are pre-processed using Discrete Wavelet Transform (DWT), Stationary Wavelet Transform (SWT), and Transverse Dyadic Wavelet Transform (TyDWT). Sub-band energy was extracted from the acquired signal using Tunable Q-factor Wavelet Transform (TQWT) and Rational Dilation Wavelet Transform (RADWT). Furthermore, Bayesian optimization is used to predict ethanol concentration. Results and Discussion: The TS-Phc sensor achieves accurate parts per million (PPM (mg/L)) prediction through Bayesian-optimized multiple regression and is verified through spectroscopic analysis. Conclusion: The proposed TS-Phc sensor provides a solution for detecting ethanol PPM (mg/L) levels and attained 96.5% accuracy. TS-Phc sensor system is suitable for environmental monitoring and biomedical diagnosis.
Cigar aging has become an important research focus; however, there is still limited systematic optimization of aging conditions. This study aimed to explore how different aging parameters affect cigar quality and to identify the best aging process for enhancing sensory evaluation. Methods: A three-factor, three-level experimental design was conducted using the Great Wall brand’s Red 132 sample, involving aging temperature (16, 20, 24°C), relative humidity (RH) (60%, 65%, 70%), and aging duration (30, 60, 90 days). This approach combined single-factor experiments with uniform design methods, using sensory evaluation scores and chemical composition as the response variables. Results: The analysis of the response variables showed that increasing the aging time decreased starch content by approximately 37.67% and reduced secondary alkaloids, while leading to an increase in sugar levels. Higher temperature (24°C) and humidity (70% RH) caused notable changes in nitrogen-containing compounds and enhanced sensory quality such as sweetness and mellowness. Pearson correlation analysis further explained the chemical reasons behind these sensory changes, indicating that amino acids were positively associated with favorable qualities like mellowness and sweetness, whereas starch and secondary alkaloids were negatively associated with permeability and offensive odors. A stepwise regression model (R² = 0.9974) was developed to quantify these relationships, pinpointing the best aging conditions as 23°C, 59 days, and 60% RH, which produced a predicted sensory score of 91.65 (confirmed at 91.5). Discussion: Aging temperature, humidity, and time significantly affect the chemical composition and sensory quality of cigars, with temperature having the strongest impact. Properly managing these factors leads to a significant reduction in large molecules and a considerable increase in small molecules, thereby enhancing the overall sensory quality. Conclusion: The optimal aging conditions for the tested cigar sample were found to be 23°C, 59 days, and 60% RH. These conditions promote chemical changes that greatly improve the aroma, flavor, and overall smoking experience.
Introduction: Currently, Cadmium (Cd2+) contamination in plant-based proteins is a significant food safety challenge that is not effectively treated by classical processing methods. Thus, the development of selective, efficient, and sustainable strategies for its remediation is essential to ensure compliance with regulatory standards and protect consumer health. Methods: EDTA-functionalized silica gel (EDTA@SiO2) sorbent was synthesized via silanization and EDTA grafting and characterized using FTIR, XRD, SEM, DLS, and zeta potential analysis. Optimization of adsorption conditions was carried out through Plackett–Burman design and response surface methodology, and selectivity and reusability were also evaluated. Results: Maximum adsorption efficiency was observed at pH 4.5, resulting in >99% Cd2+ removal from pea protein slurries. The Cd2+ concentration was reduced to 0.04 mg/kg. The sorbent retained >98% of its efficiency after five adsorption-desorption cycles. Discussion: The developed sorbent demonstrated excellent selectivity for Cd2+ in the presence of essential ions (Ca²⁺, Mg²⁺, Zn²⁺, K⁺), maintaining the nutritional quality of the supplement. Its high reusability proves its economic feasibility and suitability for repetitive use in industrial applications. Conclusion: The developed EDTA@SiO2 sorbent is an effective, selective, and reusable material for Cd2+ remediation, offering a practical and sustainable solution to enhance food safety in plant protein production.
Introduction: Sitagliptin (SIT) is a widely used oral antihyperglycaemic agent. While diverse analytical methods have emerged for its quantification, most of these methods lack green chemistry principles and suffer from limited throughput, highlighting the need for more sustainable approaches. Methods: In the present study, the aim was to develop and validate a green and efficient method for microwell spectrophotometry (MW-SPM) to quantify SIT in marketed tablet formulations. The MWSPM employs a novel, eco-friendly, and microscale single-step process to generate a colored chargetransfer complex (CTC) by reacting SIT with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ). The absorbance of the CTCs was measured by a microplate reader. The reaction conditions were optimized, and measurement accuracy was refined using UV-visible spectrophotometry, computational modeling, and response surface methodology (RSM). Results: The MW-SPM produced a stable 1:1 CTC complex with SIT, showing linearity in the range of 2-100 µg/well and a limit of quantification of 4.1 µg/well. This method effectively quantified SIT in tablet formulations, ensuring content uniformity. Based on computational modeling, the interactive site on SIT was identified, clarifying the reaction mechanism and the interaction dynamics with DDQ. The greenness of the MW-SPM was verified using GAPI and AGREE metrics. Discussion: A green, high-throughput MW-SPM was developed for Sitagliptin analysis using DDQ, and optimized via RSM for precision, sensitivity, and selectivity. The method outperforms traditional UV and HPLC techniques in efficiency, sustainability, and in practical tablet analysis. Conclusion: The MW-SPM provides a novel, high-throughput, cost-effective, and eco-friendly method for SIT quantification. Its procedural simplicity, sustainable design, and superior throughput offer significant advancements over existing spectrophotometric techniques, aligning with green analytical chemistry principles.
Sustainable biopolymeric nanoparticles or nanocomposites are gaining recognition as cutting-edge nanocarriers for biomedical applications, particularly drug delivery, providing a sustainable, long-lasting, and controlled release profile at targeted sites. These nanoparticles, sourced from natural biopolymers, offer significant advantages, including biodegradability, biocompatibility, low toxicity, and stability, making them superior alternatives to traditional metal nanoparticles. This review investigates the potential of biopolymeric nanoparticles derived from a variety of sources, including plant, animal, algal, fungal, and bacterial origins, as adaptable materials for drug delivery systems. Emphasising recent developments over the last decades, the review classifies biopolymeric nanoparticles according to their fabrication methods, such as emulsification, precipitation or desolvation, co-acervation, microfluidics including spray deposition, and their applications in biomedicine. It discusses biopolymers that act as nanocarriers commonly employed in drugdelivery systems. Additionally, the review addresses the challenges faced and future directions, providing a thorough resource for the development of customised biopolymeric nanoparticles for advancements in drug delivery.
Abstract: Geopolymer (GP) is an environmentally friendly cementitious material with an amorphous to semi-crystalline structure, synthesized from aluminosilicate precursors via chemical activation. Its preparation process is straightforward and eco-friendly, endowing the material with high compressive strength, excellent corrosion resistance, remarkable high-temperature and fire resistance, and effective ion sealing capability. As such, GP is regarded as one of the most promising green alternatives to ordinary Portland cement. However, similar to conventional cement, GP exhibits brittle failure behavior. Although it possesses high compressive strength, its tensile and flexural performance requires further improvement. Studies have shown that incorporating an appropriate amount of fiber can significantly enhance the mechanical and functional properties of GP. This review examines the effects of various commonly used fibers—including natural, steel, synthetic, and other fiber types—on the physical and mechanical characteristics of GP. Furthermore, it addresses current challenges in fiberreinforced geopolymer (F/GP) research and identifies prospective directions for future investigation and engineering applications.
Introduction The accurate and efficient detection of Uric Acid (UA) is of great importance for monitoring metabolic and clinical conditions, which are linked to human health, disease diagnosis, and medical analysis. Conventional analytical techniques often face limitations in sensitivity, cost, and operational simplicity. To address these challenges, this study introduces an electrochemical sensor utilizing a graphitic carbon nitride (g-C3N4) and cobalt oxide (Co3O4) nanocomposite designed to achieve high-performance UA sensing.Methods Co3O4 nanoparticles were synthesized through a controlled hydrothermal method, while g-C3N4 was obtained via thermal exfoliation. The as-prepared materials were combined to form the g-C3N4/Co3O4 nanocomposite. Comprehensive physicochemical characterization was performed using Scanning Electron Microscopy (SEM), Energy-Dispersive X-ray spectroscopy (EDX), X-Ray Diffraction (XRD), UV-Visible (UV-Vis) spectroscopy, and Fourier-Transform Infrared (FTIR) spectroscopy to analyze morphological and structural properties.Results Electrochemical measurements revealed that the g-C3N4/Co3O4-modified electrode exhibited a broad linear range for UA detection from 20 to 200 & micro;M, along with an exceptionally low Limit of Detection (LOD) of 0.165 & micro;M. These findings demonstrated the excellent electrocatalytic activity and sensitivity of the developed sensing platform.Discussion The superior sensing behavior can be attributed to the synergistic effect between g-C3N4 and Co3O4, where g-C3N4 provides a high surface area and excellent conductivity, while Co3O4 contributes active sites for redox reactions. This hybrid structure facilitated rapid charge transfer and efficient UA oxidation, ensuring improved analytical performance compared with conventional sensors.Conclusion The g-C3N4/Co3O4 nanocomposite-based electrochemical sensor demonstrated remarkable sensitivity, a wide detection range, and reliable stability, positioning it as a highly promising platform for uric acid detection in biomedical and environmental samples.
Introduction: Artificial Intelligence (AI) and Machine Learning (ML) are currently integrated with pharmaceutical analysis techniques used for drug identification and separation. The integration of analytical techniques such as spectroscopy, chromatography, and mass spectrometry significantly increases sensitivity, specificity, and processing speed. In this review, AI/ML utilization in the identification of different pharmaceutical compounds is presented, including enhancement of performance, classification techniques, and current limitations in pharmaceutical, clinical, and environmental applications. Methods: An extensive review of literature was conducted, reviewing peer-reviewed journals and newer advancements involving AI/ML in pharmaceutical analytical techniques. The considered models are Support Vector Machines (SVM), Convolutional Neural Networks (CNN), decision trees, and ensemble methods. Studies were categorized based on different drug types to identify challenges related to chemical structures, detection, and comparisons to traditional methods. Results and Discussion: The AI/ML models produced have improved ability to detect lowconcentration analytes in complex matrices such as blood, milk, wastewater, and pharmaceutical products. These techniques significantly surpass conventional analytical techniques in detection limits, stability, and computation speed. AI-based spectroscopic data supports rapid and accurate classification, especially in multi-residue analyses. However, model interpretability, data heterogeneity, hardware requirements, and regulation remain major challenges to widespread adoption. Conclusion: Pharmaceutical analytics with the application of AI/ML is of great value for detecting, classifying, and separating compounds, especially in challenging environments. Yet, to reach their maximum capability, issues related to data quality, model interpretability, cross-disciplinary expertise, and regulatory adoption must be addressed. Future research must focus on the development of standardized procedures, enhancing model generalizability, and improving accessibility for broader application in laboratory and field analysis.
Introduction This study introduces a previously unreported sulfonated Naphthalimide derivative (NAP) designed as a multifunctional molecular scaffold for integrated fluorescence sensing and antimicrobial applications. Following functionalization with 3-(methylthio)propylamine, the compound was successfully immobilized onto silver nanoparticles (AgNPs) via thiomethyl anchoring, yielding a stable and highly functional nanohybrid system. The photophysical characteristics and selective metal ion sensing behavior of the resulting NAP-AgNPs were systematically evaluated. Importantly, this work constitutes the first example of sulfonate-bearing naphthalimide-functionalized AgNPs that simultaneously act as nanoparticle stabilizers, fluorescent sensing elements, and antimicrobial agents, thereby establishing a new multifunctional strategy for naphthalimide-silver nanomaterials.Methods NAP was synthesized via the reaction of 4-sulfo-1,8-naphthalic anhydride with 3- (methylthio)propylamine and subsequently immobilized onto AgNPs through its thiomethyl groups. Structural and morphological characterizations were performed using NMR, FTIR, SEM, XRD, and DLS techniques. Photophysical properties were investigated by UV-Vis and fluorescence spectroscopy. Interaction studies with Cd2+, Mn2+, Cu2+, Co2+, Ni2+, Zn2+, Fe2+, Fe3+, Pb2+, Hg2+, and Ag+ ions were carried out. Antimicrobial activity was assessed against Gram- positive and Gram-negative bacteria.Results NAP exhibited strong fluorescence emission at 520 nm, while NAP-AgNPs showed surface plasmon resonance with complete fluorescence quenching. Selective optical responses to Fe2+, Fe3+, Hg2+, and Ag+ were observed in both UV-Vis and fluorescence spectra, indicating promising sensing ability. Additionally, NAP-AgNPs displayed significant antimicrobial activity.Discussion The study demonstrates that sulfonated NAP derivatives can serve as sensitive and selective probes for specific metal ions. The incorporation into AgNPs provided unique plasmonic properties, which may enhance sensing applications and enable dual-functional materials with antimicrobial capability.Conclusion This work highlights the potential of NAP and NAP-AgNPs as photofunctional materials for selective metal ion sensing and as effective antimicrobial agents, suggesting future applications in environmental monitoring and biomedical fields.
Abstract: Nitrosamines (NA) are potent genotoxic impurities, continuously reported due to their mutagenic and carcinogenic effects in animal species. Recently, these substances were detected as contaminants in various pharmaceutical products, prompting several product recalls due to risks to public health. Certain derivatives Of Angiotensin II Receptor Blockers (ARBs), such as losartan, valsartan, and olmesartan, have been identified as problematic in the presence of NAs, primarily due to contamination-related factors. Other drugs and classes, including nizatidine, metformin, quetiapine, sitagliptin, and amitriptyline, have also been reported as potential sources of NA contamination during pharmaceutical production. This review aims to provide a comprehensive reference for scientists, technical analysts, and regulatory bodies regarding NAs, focusing on their possible presence in drug synthesis and pharmaceutical production. The review integrates published information concerning contamination sources, genotoxic effects, physicochemical properties, regulatory guidelines, analytical methods, and sample pre-treatment strategies. An updated overview of regulatory aspects highlights the need for continuous revisions, considering available analytical technologies capable of detecting NAs at the lowest possible concentrations. The established detection limits must align with regulatory recommendations, which take into account daily drug intake and its relationship with toxicological effects. Much of the information published in the literature is applicable to drug products, and it is important to develop new strategies in regulatory, scientific, and technical areas that address the new challenges arising from a focus on continuous prevention. Future pharmaceutical product design should allocate more resources to preventing NA formation, prioritizing the selection of molecules with lower contamination risks or adopting alternative synthetic routes. This integrative perspective enhances comprehension and serves as complementary material for new investigations concerning NA and pharmaceuticals.
Abstract: Heavy metal pollution from anthropogenic activities poses a threat to marine ecosystems, causing complex, often sub-lethal biochemical disturbances in aquatic organisms. Studies using traditional toxicological assessments mainly offer limited insight into the underlying mechanisms of metal- induced stress. While metabolomics, in particular Nuclear Magnetic Resonance (NMR) and Mass Spectrometry (MS) based studies, has emerged as an important tool in investigating organism-level responses at a systems biology level. This review has made effort in compiling current metabolomic research on the impacts of heavy metals, that includes cadmium (Cd), mercury (Hg), copper (Cu), zinc (Zn), arsenic (As), and silver (Ag), on marine model organisms such as the Manila clam (Ruditapes philippinarum), green mussel (Perna viridis), Mediterranean mussel (Mytilus galloprovincialis), oyster (Crassostrea hongkongensis), various fish species, and crustaceans. It is observed that there are consistent metabolic disruptions in pathways related to energy metabolism (e.g., ATP, succinate), osmoregulation (e.g., taurine, betaine), and amino acid balance (e.g., branched-chain amino acids, glutamate). The metabolic responses were mainly tissue-specific and depended on life stage and environmental variables, such as salinity or co-exposure to other pollutants. Altogether, metabolomics provides sensitive, early biomarkers of heavy metal stress. This can contribute to a deeper understanding of ecological risk assessment and to develop more effective marine conservation strategies.
Introduction This work reports the preparation of a series of novel Mannich bases derived from the imidazo[1,2-a]pyridine scaffold. The development of a simple new purification strategy using preparative Thin-Layer Chromatography (TLC) is described. This technique is highly efficient, economical, and readily accessible in standard laboratory settings. Methods The crude product was dissolved in a minimal amount of dichloromethane and applied as a uniform band onto preparative silica gel TLC plates (silica gel 60 F254, 20 & times; 20 cm, 2 mm thickness). Plate development was conducted using an optimized solvent system, typically ethyl acetate/hexane (1:1, v/v). Following development, the plates were dried and examined under UV light at 254 nm. Results The target molecules were obtained in high yields (81-95) through a one-pot three-component Mannich reaction. Discussion Due to the limited availability of conventional chromatographic equipment during the COVID-19 period, an alternative purification protocol based on preparative TLC was optimized. The structures of all products were confirmed by H-1 NMR, C-13 NMR, IR, and UV spectroscopy. Conclusion:The proposed method offers a rapid, low-cost and solvent-saving approach for the puri-fication of small-scale heterocyclic libraries.
Introduction: River dredging generates large volumes of high-water-content sludge, and reuse-oriented treatment can reduce disposal pressure and environmental risk. This study quantifies the influence of bentonite dosage on the strength, deformability, and pore structure of cementstabilized dredged silty sludge, and examines its field applicability at a groundwater-sensitive metro portal. Methods: Specimens were prepared with 6-25% cement and 0-12% calcium bentonite. Unconfined compressive strength (UCS), failure strain, and secant modulus E50 were measured at 7, 28, and 90 days. The 28-day microstructural interpretation was based on SEM, XRD phase-related features, and mercury intrusion porosimetry (MIP) pore metrics. Engineering verification was conducted using 28-day cores from a triple-axis mixed portal zone, and a coupled seepage-deformation model was calibrated using the measured UCS and permeability. Results: UCS increased with bentonite content to an optimum at 9% and declined at higher contents; the 7-day UCS reached approximately 45% of the 90-day value, and the 28-day UCS exceeded approximately 75%. MIP showed reduced accessible pore volume at moderate bentonite contents, consistent with gains in UCS and E50, while SEM indicated a denser and more continuously cemented fabric. In the field verification, the 28-day core UCS was 0.6-1.0 MPa in weak reinforcement zones and >1.0 MPa in strong reinforcement zones, with a maximum value of 1.48 MPa. Permeability was on the order of 10-6 cm/s, with a minimum value of 3.27 & times; 10-8 cm/s. The coupled seepage-deformation model reproduced the monitored settlement trend, with discrepancies typically within 30%. Discussion: The results indicate that moderate bentonite addition can refine the pore structure and improve the mechanical performance of cement-stabilized dredged silty sludge. The consistency between the laboratory observations and field verification suggests that bentonite contributes positively to both strength development and seepage control in groundwater-sensitive reinforcement applications. Conclusion: Overall, 9% bentonite provides a practical balance between pore refinement and mechanical performance, and the combined laboratory and field evidence supports its use for portal reinforcement where seepage control is critical.
Introduction: Electrochemical sensors have a key role in monitoring the existence of organic chemicals found in samples. Discharging industrial toxic chemicals and the incomplete burning of coal have been linked to carcinogenic effects on humans. As such, hazardous organic chemicals must be determined and monitored. Detecting these organic compounds is crucial due to their detrimental environmental impact. Methods: Researchers have shown significant interest in the development of nanomaterials-based electrochemical sensors for detecting organic compounds. Results: Different databases were searched (e.g., Google Scholar, Web of Science, SCOPUS, ScienceDirect, etc.), and it was found that organic chemical hazards i.e., nitrophenols, bisphenol A, resorcinol, catechol, nitrotoluenes, etc are commonly used in different products that are being used in our daily life routine. Those substances, including their byproducts, raise serious human health concerns. Discussion: With their excellent surface-to-volume ratio, strong catalytic properties, and easy miniaturization, nanocomposite materials are now the leading ‘electrode materials’ for sensing toxic chemical compounds. Conclusion: The authors attempted to summarise the recent advances in electrochemical sensing of other analytes (as chemical hazards) in various samples or bodies, including water, food, pharmaceuticals, and milk, based on the literature reported from 2017 to 2025.
The quality of veterinary pharmaceutical products has an impact on pharmacotherapy, animal health, and food safety. Therefore, analytical development and quality control are of utmost importance, providing effective and reliable analytical methods that are also aligned with the United Nations Sustainable Development Goals. Objective This study aimed to develop and validate an eco-efficient, stability-indicating method to evaluate IVE for veterinary use by HPLC, based on the principles of Green Analytical Chemistry (GAC) and White Analytical Chemistry (WAC). Methods The method was performed in isocratic mode at room temperature. The mobile phase consisted of ethanol: purified water (75:25, v/v); injection volume was 10 mu L; flow rate was 0.8 mL min(-1); separation was carried out on a Kinetex XB column (150 & times; 4.6 mm, 5 & micro;m) at 245 nm. The eco-efficiency of the method was evaluated by the National Environmental Methods Index (NEMI), Eco-Scale Assessment (ESA), Analytical Greenness Evaluation (AGREE), Green Analytical Procedure Index (GAPI), Blue Applicability Grade Index (BAGI), Carbon Footprint Reduction Index (CaFRI), and Click Analytical Chemistry Index (CACI). Results The proposed method was shown to be linear in the range of 1 to 10 mu g mL-1, and stability-indicating based on the stress test; it was precise (RSD < 2%), and accurate (average recovery of 98.99%). Robustness was proven by the Youden & Steiner test. Furthermore, it was demonstrated to be eco-efficient, as evidenced by NEMI (four green quadrants), ESA (90 points), AGREE (0.63 points), GAPI (predominantly yellow and green), CaFRI (68 points), BAGI (65 points), and CACI (75 points). Discussion Thus, the results of the proposed validated method, according to the specifications, were considered an eco-efficient alternative for the evaluation of IVE in an injectable solution. Moreover, the HPLC method was considered green, practical, aligned with the Sustainable Development Goals, and a valuable contribution to the quality control sector. Conclusions The proposed method is an ecologically sustainable option for the analysis of IVE for veterinary use, as it is in accordance with the principles of green and white analytical chemistry.
Introduction This pilot study aimed to identify novel serum protein biomarkers distinguishing antepartum stillbirth from live birth cases using LC-MS-based proteomics. Methods After obtaining ethical approval and the patient consent, serum from three stillbirth cases and three live birth controls was analyzed using liquid chromatography-mass spectrometry. Z-scores and t-tests identified significantly differentially expressed proteins (p < 0.05), with the top candidate proteins being evaluated against validated against clinical profiles of cases and controls. Results Of 3,076 detected proteins, 472 were unique to the stillbirth group, and 1,275 were unique to the control group. We identified 100 proteins that were significantly downregulated in stillbirth cases compared to controls, while 48 proteins were significantly upregulated. Subsequently, the top 14 proteins were evaluated in relation to the clinical complications of the subjects. Among these, Vacuolar protein sorting-associated protein 13D, immunoglobulin kappa variable 3-20, and Lysozyme C demonstrated markedly distinct expression patterns.Discussion These novel proteins reflect vascular and placental dysfunction, cellular stress, and immune dysregulation that may contribute to stillbirth pathogenesis, acting as a multi-marker diagnostic panel. Conclusion This study identifies three promising protein biomarker candidates for stillbirth prediction, paving the way for validation in larger cohorts and clinical assay development.
Abstract: Microplastics (MPs) have gained increasing recognition as ubiquitous contaminants with a widespread presence across diverse environmental compartments. Characterized by a high specific surface area, small particle size, and strong adsorption affinity for pollutants, MPs pose considerable environmental concerns. Over recent decades, substantial quantities of MPs from varied sources have been released globally, and their intricate environmental behaviors present significant risks to ecosystem stability. Landfills, acting as major reservoirs for plastic waste, have been identified as critical sources of MP contamination. This review synthesizes recent advancements in understanding the occurrence and environmental behaviors of MPs in landfill environments, with particular emphasis on MP-derived dissolved organic matter. Furthermore, it critically reviews and discusses the progress and limitations of current characterization methodologies—covering sample collection, pretreatment, and detection techniques—based on both physical properties and chemical composition. Special attention is given to the urgent need for developing robust analytical approaches to assess the ecological toxicity of MPs and their associated additives. Finally, future research perspectives and directions concerning MPs in landfill settings are proposed.
Introduction: As the core water source for the Middle Route of China's South-to-North Water Diversion Project, the Danjiangkou Reservoir necessitates stringent water protection as a key national strategic requirement. Nanofiltration (NF) is a promising technology for water purification. Compared to other materials, commercial NF membranes exhibit less than 40% rejection rate for neutral small-molecule organic pollutants with molecular weights below 200 Da and a water flux of only about 10 L·m-2·h-1·bar-1, restricting their practical application. Methods: In this study, a poly(methyl methacrylate) (PMMA)/poly (vinyl alcohol) (PVA) blend nanofiltration membrane was fabricated by dissolving PMMA and PVA in N,N-dimethylformamide (DMF) to prepare a casting solution. These membranes were followed by blade coating, solvent evaporation, and phase inversion, achieving effective separation for chlorinated phenolic disinfection byproduct (DBP) removal. Results: When the PMMA/PVA ratio was 7.5:2.5, the rejection rates of the blend nanofiltration membrane were 56.1% for 4-chlorophenol and 72.2% for 2,4-dichlorophenol, respectively, and water fluxes were 49.2 and 47.7 L·m-2·h-1·bar-1. In real water samples, the rejection rates for 4-chlorophenol and 2,4-dichlorophenol were 54.65% and 66.42%, respectively. The water fluxes for 4-chlorophenol and 2,4-dichlorophenol in real water samples were 16.0 and 4.1 L·m-2·h-1·bar-1, respectively. Discussion: These results provide a viable alternative membrane material for the separation and removal of neutral small-molecule organic pollutants from wastewater. Conclusion: The PMMA/PVA blend membrane was constructed using a simple blending method, which exhibited rejection rates of 56.1% and 72.2% for 4-chlorophenol and 2,4-dichlorophenol, respectively. Compared to commercial NF membranes, which usually exhibit rejection of less than 40% for neutral small‑molecule pollutants, this blend membrane shows significant improvements.
