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Journal of Hazardous Materials Jul 2024The surge in face mask use due to COVID-19 has raised concerns about micro(nano)plastics (MNPs) from masks. Herein, focusing on fabric structure and polymer composition,...
The surge in face mask use due to COVID-19 has raised concerns about micro(nano)plastics (MNPs) from masks. Herein, focusing on fabric structure and polymer composition, we investigated MNP generation characteristics, mechanisms, and potential risks of surgical polypropylene (PP) and fashionable polyurethane (PU) masks during their wearing and photoaging based on stereomicroscope, μ-Fourier transform infrared spectroscopy (μ-FTIR), and scanning electron microscope (SEM) techniques. Compared with new PP and PU masks (66 ± 16 MPs/PP-mask, 163 ± 83 MPs/PU-mask), single- and multiple-used masks exhibited remarkably increased MP type and abundance (600-1867 MPs/PP-mask, 607-2167 MPs/PU-mask). Disinfection exacerbated endogenous MP generation in masks, with washing (416 MPs/PP-mask, 30,708 MPs/PU-mask) being the most prominent compared to autoclaving (219 MPs/PP-mask, 553 MPs/PU-mask) and alcohol spray (162 MPs/PP-mask, 18,333 MPs/PU-mask). Photoaging led to massive generation of MPs (8.8 × 10-3.7 × 10 MPs/PP-layer, 1.0 × 10 MPs/PU-layer) and NPs (5.2 × 10-3.6 × 10 NPs/PP-layer, 3.5 × 10 NPs/PU-layer) from masks, presenting highly fabric structure-dependent aging modes as "fragmentation" for fine fiber-structure PP mask and "erosion" for 3D mesh-structure PU mask. The MNPs derived from PP/PU mask caused significant deformities of Zebrafish (Danio rerio) larvae. These findings underscore the potential adverse effects of masks on humans and aquatic organisms, advocating to enhance proper use and rational disposal for masks.
PubMed: 38959827
DOI: 10.1016/j.jhazmat.2024.135089 -
Advances in Colloid and Interface... Jun 2024Adsorption of surfactants to fluid interfaces occurs in numerous technological and daily-life contexts. The coverage at the interface and other properties of the formed...
Adsorption of surfactants to fluid interfaces occurs in numerous technological and daily-life contexts. The coverage at the interface and other properties of the formed adsorption layers determine the performance of a surfactant with regard to the desired application. Given the importance of these applications, there is a great demand for the comprehensive characterization and understanding of surfactant adsorption layers. In this review, we provide an overview of suitable experimental and simulation-based techniques and review the literature in which they were used for the investigation of surfactant adsorption layers. We come to the conclusion that, while these techniques have been successfully applied to investigate Langmuir monolayers of water-insoluble surfactants, their application to the study of Gibbs adsorption layers of water-soluble surfactants has not been fully exploited. Finally, we emphasize the great potential of these methods in providing a deeper understanding of the behavior of soluble surfactants at interfaces, which is crucial for optimizing their performance in various applications.
PubMed: 38959812
DOI: 10.1016/j.cis.2024.103237 -
Food Chemistry Jun 2024A selection of formulations with different polymers and concentrations of green tea extract was conducted for application as interleafs in sliced meat products. Films...
A selection of formulations with different polymers and concentrations of green tea extract was conducted for application as interleafs in sliced meat products. Films were formulated using cellulose acetate, corn starch, and chitosan with the addition of 1.0, 2.5, and 5.0% green tea extract. Higher antioxidant activity was observed with the 1.0% concentration of green tea extract (P < 0.05), regardless of the formulation, with continuous release of the extract for up to 60 days and average IC of 0.09 and 0.31 mg/mL for the corn starch and chitosan active films, respectively. Interleafing the sliced ham resulted in lower lipid oxidation after 60 days of storage (P < 0.05). Starch-based films with green tea extract were effective, significantly reducing lipid oxidation in sliced and interleafed cooked ham, suggesting their potential to extend the shelf life of these refrigerated products.
PubMed: 38959804
DOI: 10.1016/j.foodchem.2024.140159 -
Food Chemistry Jun 2024Aflatoxin B (AFB), a pernicious constituent of the aflatoxin family, predominantly contaminates cereals, oils, and their derivatives. Acknowledged as a Class I...
Aflatoxin B (AFB), a pernicious constituent of the aflatoxin family, predominantly contaminates cereals, oils, and their derivatives. Acknowledged as a Class I carcinogen by the World Health Organization (WHO), the expeditious and quantitative discernment of AFB remains imperative. This investigation delineates that aluminum ions can precipitate the coalescence of iodine-modified silver nanoparticles, thereby engendering hot spots conducive for label-free AFB identification via Surface-Enhanced Raman Spectroscopy (SERS). This methodology manifests a remarkable limit of detection (LOD) at 0.47 fg/mL, surpassing the sensitivity thresholds of conventional survey techniques. Moreover, this method has good anti-interference ability, with a relative error of less than 10% and a relative standard deviation of less than 6% in quantitative results. Collectively, these findings illuminate the substantial application potential and viability of this approach in the quantitative analysis of AFB, underpinning a significant advancement in food safety diagnostics.
PubMed: 38959803
DOI: 10.1016/j.foodchem.2024.140231 -
Food Chemistry Jul 2024Staphylococcus aureus contamination continues to be a harmful foodborne pathogen threatening of human health, and there is a growing need for rapid detection...
Staphylococcus aureus contamination continues to be a harmful foodborne pathogen threatening of human health, and there is a growing need for rapid detection technologies. This study proposed a novel paper biosensor based on a polydiacetylene (PDA) polymer functionalized fibrinogen (Fg) for the detection of S. aureus in food sources. The fluorophore was developed based on the high binding ability of fibrinogen-binding proteins on the surface of S. aureus. This binding caused twisting in the PDA backbone, leading to changes in chromatic and fluorescent. The detection limit of this method was 50.1 CFU/mL for S. aureus-contaminated foodstuffs and 65.0 CFU/mL for the pure S. aureus culture, and the novelty came from its rapidity and selectivity for S. aureus compared to other foodborne bacteria. In summary, the present work provides a rapid detection method for S. aureus detection, which will help in addressing food safety-related issues.
PubMed: 38959795
DOI: 10.1016/j.foodchem.2024.140291 -
Journal of Environmental Management Jul 2024Ultrafiltration technology, separating water from impurities by the core membrane, is an effective strategy for treating wastewater to meet the ever-growing requirement...
Ultrafiltration technology, separating water from impurities by the core membrane, is an effective strategy for treating wastewater to meet the ever-growing requirement of clean and drinking water. However, the similar nature of hydrophobic organic pollutants and the membrane surface leads to severe adsorption and aggregation, resulting unavoidable membrane degradation of penetration and rejection. The present study presents a novel block amphiphilic polymer, polyethersulfone-g-carboxymethyl chitosan@MWCNT (PES-g-CMC@MWCNT), which is synthesized by grafting hydrophobic polyethersulfone to hydrophilic carboxymethyl chitosan in order to suspend CMC in organic solution. A mixture of hydrophilic carboxymethyl chitosan and hydrophobic polymers (polyethersulfone), in which hydrophilic segments are bonded to hydrophobic segments, could provide hydrophilic groups, as well as gather and remain stable on membrane surfaces by their hydrophobic interaction for improved compatibility and durability. The resultant ultrafiltration membranes exhibit high water flux (198.10 L m·h), suitable hydrophilicity (64.77°), enhanced antifouling property (82.96%), while still maintains excellent rejection of bovine serum albumin (91.75%). There has also been an improvement in membrane cross-sectional morphology, resulting in more regular pores size (47.64 nm) and higher porosity (84.60%). These results indicate that amphiphilic polymer may be able to significantly promote antifouling and permeability of ultrafiltration membranes.
PubMed: 38959769
DOI: 10.1016/j.jenvman.2024.121611 -
Spectrochimica Acta. Part A, Molecular... Jun 2024Terahertz (THz) technology integration with nanomaterials is receiving excellent attention for next-generation applications, including enhanced imaging and...
Terahertz (THz) technology integration with nanomaterials is receiving excellent attention for next-generation applications, including enhanced imaging and communication. The excellent optical properties in THz domain can lead to preparation of low-cost CMOS camera which can convert THz radiation into optical signal in very efficient manner. In the present study, we have studied the properties of Zinc Sulfide quantum dots (ZnS QDs) embedded with Polyvinyl Alcohol (PVA) composites films using THz Signal at room temperature. The optical characterizations such as refractive index, absorption coefficients and dielectric constants of these samples were measured in the 0.1-2.0 THz range. Additionally, optical impedance, surface roughness, and reflection coefficient in TE and TM mode between 0.1 and 2.0 THz range were determined for these samples based on surface roughness-based reflection and scattering properties. The surface roughness factor was used to measure the optical impedance of the ZnS QDs based polymer films. The measured values of the absorption coefficient at 266 nm are compared with THz radiation, and the refractive indices of these samples range from 1.75 to 2.0. Finally, these samples were subjected to UV light excitation (λ = 266 nm) of 0.15 ns duration and 400 nm for the fluorescence and corresponding life time measurements. We observed two numbers of fluorescence lines in nanosecond based excited domain whereas 400 nm excitation-based fluorescence life time lies between 13.8-11.39 ns range along with shift in fluorescence lines between 538.7 to 560.7 nm, respectively.
PubMed: 38959691
DOI: 10.1016/j.saa.2024.124697 -
Journal of Chromatography. A Jun 2024Polymer monoliths can be polymerised within different molds, but limited options are available for the preparation of free-standing polymer monoliths for analytical...
Polymer monoliths can be polymerised within different molds, but limited options are available for the preparation of free-standing polymer monoliths for analytical sample preparation, and in particular, solid-phase extraction (SPE). Commercial melamine-formaldehyde sponges can be used as supports for the preparation of polymer monoliths, due its flexibility, giving various shapes to monoliths. Herein, the crosslinker/porogen ratio of highly porous sponge-nested divinylbenzene (DVB) polymer monoliths has been evaluated. Monoliths prepared using different crosslinker/porogen ratios were applied to the extraction of bisphenol F, bisphenol A, bisphenol AF, and bisphenol B. Monoliths containing 50 wt % DVB and 50 wt % porogens presented the highest recovery of bisphenols. Under the optimised conditions, the developed method showed a linear range between 2.5 µg L and 150 µg L for BPA and BPAF, and between 5 µg L and 150 µg L for BPB and BPF. The limits of detection (LOD, S/N = 3) and limits of quantification (LOQ, S/N = 10) ranged from 0.36 µg L to 1.09 µg L, and from 1.20 µg L to 3.65 µg L, respectively. The recoveries for spiked bisphenols (10 µg L) in tap water and water contained in a polycarbonate containers were between 82 % and 114 %.
PubMed: 38959657
DOI: 10.1016/j.chroma.2024.465124 -
Spectrochimica Acta. Part A, Molecular... Jun 2024Coffee is a globally consumed commodity of substantial commercial significance. In this study, we constructed a fluorescent sensor array based on two types of polymer...
Coffee is a globally consumed commodity of substantial commercial significance. In this study, we constructed a fluorescent sensor array based on two types of polymer templated silver nanoclusters (AgNCs) for the detection of organic acids and coffees. The nanoclusters exhibited different interactions with organic acids and generated unique fluorescence response patterns. By employing principal component analysis (PCA) and random forest (RF) algorithms, the sensor array exhibited good qualitative and quantitative capabilities for organic acids. Then the sensor array was used to distinguish coffees with different processing methods or roast degrees and the recognition accuracy achieved 100%. It could also successfully identify 40 coffee samples from 12 geographical origins. Moreover, it demonstrated another satisfactory performance for the classification of pure coffee samples with their binary and ternary mixtures or other beverages. In summary, we present a novel method for detecting and identifying multiple coffees, which has considerable potential in applications such as quality control and identification of fake blended coffees.
PubMed: 38959644
DOI: 10.1016/j.saa.2024.124760 -
Biomaterials Jun 2024Immunotherapy is regarded as one of the most promising approaches for treating tumors, with a multitude of immunotherapeutic thoughts currently under consideration for... (Review)
Review
Immunotherapy is regarded as one of the most promising approaches for treating tumors, with a multitude of immunotherapeutic thoughts currently under consideration for the lethal glioblastoma (GBM). However, issues with immunotherapeutic agents, such as limited in vivo stability, poor blood-brain barrier (BBB) penetration, insufficient GBM targeting, and represented monotherapy, have hindered the success of immunotherapeutic interventions. Moreover, even with the aid of conventional drug delivery systems, outcomes remain suboptimal. Biomimetic strategies seek to overcome these formidable drug delivery challenges by emulating nature's intelligent structures and functions. Leveraging the variety of biological structures and functions, biomimetic drug delivery systems afford a versatile platform with enhanced biocompatibility for the co-delivery of diverse immunotherapeutic agents. Moreover, their inherent capacity to traverse the BBB and home in on GBM holds promise for augmenting the efficacy of GBM immunotherapy. Thus, this review begins by revisiting the various thoughts and agents on immunotherapy for GBM. Then, the barriers to successful GBM immunotherapy are analyzed, and the corresponding biomimetic strategies are explored from the perspective of function and structure. Finally, the clinical translation's current state and prospects of biomimetic strategy are addressed. This review aspires to provide fresh perspectives on the advancement of immunotherapy for GBM.
PubMed: 38959533
DOI: 10.1016/j.biomaterials.2024.122694