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1.
J Hazard Mater ; 470: 134124, 2024 May 15.
Article de Anglais | MEDLINE | ID: mdl-38565020

RÉSUMÉ

Microplastics are known to negatively affect anaerobic digestion (AD) of waste activated sludge. However, whether thermal hydrolysis (TH) pretreatment alters the impact of microplastics on sludge AD remains unknown. Herein, the effect of TH on the impact of polyethylene (PE) microplastics in sludge AD was investigated. The results showed that the inhibition of methane production by PE at 100 particles/g total solids (TS) was reduced by 31.4% from 12.1% to 8.3% after TH at 170 °C for 30 min. Mechanism analysis indicated TH reduced the potential for reactive oxygen species production induced by PE, resulting in a 29.1 ± 5.5% reduction in cell viability loss. In addition, additive leaching increased as a result of rapid aging of PE microplastics by TH. Acetyl tri-n-butyl citrate (ATBC) release from PE with 10 and 100 particles/g TS increased 11.5-fold and 8.6-fold after TH to 68.2 ± 5.5 µg/L and 124.0 ± 5.1 µg/L, respectively. ATBC at 124.0 µg/L increased methane production by 21.4%. The released ATBC enriched SBR1031 and Euryarchaeota, which facilitate the degradation of proteins and promote methane production. This study reveals the overestimated impact of PE microplastics in sludge AD and provides new insights into the PE microplastics-induced impact in practical sludge treatment and anaerobic biological processes.


Sujet(s)
Méthane , Microplastiques , Polyéthylène , Eaux d'égout , Anaérobiose , Microplastiques/toxicité , Hydrolyse , Polyéthylène/toxicité , Méthane/métabolisme , Élimination des déchets liquides/méthodes , Température élevée , Polluants chimiques de l'eau/toxicité , Bioréacteurs
2.
ACS Appl Bio Mater ; 2024 Apr 25.
Article de Anglais | MEDLINE | ID: mdl-38661721

RÉSUMÉ

Drug-coated balloon (DCB) therapy is a promising endovascular treatment for obstructive arterial disease. The goal of DCB therapy is restoration of lumen patency in a stenotic vessel, whereby balloon deployment both mechanically compresses the offending lesion and locally delivers an antiproliferative drug, most commonly paclitaxel (PTX) or derivative compounds, to the arterial wall. Favorable long-term outcomes of DCB therapy thus require predictable and adequate PTX delivery, a process facilitated by coating excipients that promotes rapid drug transfer during the inflation period. While a variety of excipients have been considered in DCB design, there is a lack of understanding about the coating-specific biophysical determinants of essential device function, namely, acute drug transfer. We consider two hydrophilic excipients for PTX delivery, urea (UR) and poly(ethylene glycol) (PEG), and examine how compositional and preparational variables in the balloon surface spray-coating process impact resultant coating microstructure and in turn acute PTX transfer to the arterial wall. Specifically, we use scanning electron image analyses to quantify how coating microstructure is altered by excipient solid content and balloon-to-nozzle spray distance during the coating procedure and correlate obtained microstructural descriptors of coating aggregation to the efficiency of acute PTX transfer in a one-dimensional ex vivo model of DCB deployment. Experimental results suggest that despite the qualitatively different coating surface microstructures and apparent PTX transfer mechanisms exhibited with these excipients, the drug delivery efficiency is generally enhanced by coating aggregation on the balloon surface. We illustrate this microstructure-function relation with a finite element-based computational model of DCB deployment, which along with our experimental findings suggests a general design principle to increase drug delivery efficiency across a broad range of DCB designs.

3.
Luminescence ; 39(4): e4746, 2024 Apr.
Article de Anglais | MEDLINE | ID: mdl-38644460

RÉSUMÉ

The use of photochromism to increase the credibility of consumer goods has shown great promise. To provide mechanically dependable anticounterfeiting nanofibres, it has also been critical to improve the engineering processes of authentication patterns. Mechanically robust and photoluminescent electrospun poly(ethylene oxide)/glass (PGLS) nanofibres (150-350 nm) immobilized with nanoparticles of lanthanide-doped aluminate (NLA; 8-15 nm) were developed using electrospinning technology for anticounterfeiting purposes. The provided nanofibrous membranes changed colour from transparent to green when irradiated with ultraviolet light. By delivering NLA with homogeneous distribution without aggregations, we were able to keep the nanofibrous membrane transparent. When excited at 365 nm, NLA@PGLS nanofibres showed an emission intensity at 517 nm. The hydrophobicity of NLA@PGLS nanofibres improved by raising the pigment concentration as the contact angle was increased from 146.4° to 160.3°. After being triggered by ultraviolet light, NLA@PGLS showed quick and reversible photochromism without fatigue. It was shown that the suggested method can be applied to reliably produce various anticounterfeiting materials.


Sujet(s)
Verre , Nanofibres , Polyéthylène glycols , Rayons ultraviolets , Nanofibres/composition chimique , Polyéthylène glycols/composition chimique , Verre/composition chimique , Taille de particule , Propriétés de surface
4.
NanoImpact ; : 100508, 2024 Apr 23.
Article de Anglais | MEDLINE | ID: mdl-38663501

RÉSUMÉ

The objective of this investigation was to evaluate the influence of micro- and nanoplastic particles composed of polyethylene terephthalate (PET), a significant contributor to plastic pollution, on human brain vascular pericytes. Specifically, we delved into their impact on mitochondrial functionality, oxidative stress, and the expression of genes associated with oxidative stress, ferroptosis and mitochondrial functions. Our findings demonstrate that the exposure of a monoculture of human brain vascular pericytes to PET particles in vitro at a concentration of 50 µg/ml for a duration of 3, 6 and 10 days did not elicit oxidative stress. Notably, we observed a reduction in various aspects of mitochondrial respiration, including maximal respiration, spare respiratory capacity, and ATP production in pericytes subjected to PET particles for 3 days, with a mitochondrial function recovery at 6 and 10 days. Furthermore, there were no statistically significant alterations in mitochondrial DNA copy number, or in the expression of genes linked to oxidative stress and ferroptosis, but an increase of the expression of the gene mitochondrial transcription factor A (TFAM) was noted at 3 days exposure. These outcomes suggest that, at a concentration of 50 µg/ml, PET particles do not induce oxidative stress in human brain vascular pericytes. Instead, at 3 days exposure, PET exposure impairs mitochondrial functions, but this is recovered at 6-day exposure. This seems to indicate a potential mitochondrial hormesis response (mitohormesis) is incited, involving the gene TFAM. Further investigations are warranted to explore the stages of mitohormesis and the potential consequences of plastics on the integrity of the blood-brain barrier and intercellular interactions. This research contributes to our comprehension of the potential repercussions of nanoplastic pollution on human health and underscores the imperative need for ongoing examinations into the exposure to plastic particles.

5.
Health Sci Rep ; 7(4): e2047, 2024 Apr.
Article de Anglais | MEDLINE | ID: mdl-38655418

RÉSUMÉ

Background and Aims: Bowel preparation is considered as major obstacle before colonoscopy, and it is often reported as the most feared part of the procedure. The aim of this study is to determine the difference in efficacy between a split dose of PEG and the previous day regimen in cleaning the colon, using Boston bowel preparation scale. In addition, also to evaluate patient satisfaction regarding the modality of preparation. Methods: The study included 200 hospitalized patients undergoing colonoscopy at Beirut hospitals between 2021 and 2023. One of the two regimens will be prescribed randomly to the patients before colonoscopy: 98 (49%) in Group A (patients treated with PEG preparation as a split dose for 2 days), and 102 (51%) in Group B (patients taking PEG preparation as a whole dose). Data was analyzed using SPSS version 25. Results: Patients were distributed between 105 (52.5%) males and 95 (47.5%) females. The top two indications for colonoscopy were bleeding (34%), change in bowel habits (constipation/diarrhea) (32%). Patients experienced adverse events noting cramps (48.5%), stomach ache (32%), headache (31%), vomiting (53%), nausea (53%), sleep disturbance (27%), bloating (26.5%), and malaise (26%). A statistically significant difference (p = 0.040) was detected in sleep disturbance: 20.4% of patients in group A and 33.3% of patients in group B. The average satisfaction score was 3.02 ± 1.03 over 4 (Group A) and 3.04 ± 0.99 over 4 (Group B) (p = 0.896). The average BBPS was 8.07 ± 1.14 (Group A) and 8.28 ± 1.0 (Group B) (p = 0.162). Conclusion: The two administrations were almost similar in term of satisfaction and BBPS. As multiple factors like age, sexe, comorbidities may contribute in altering how much a given drug is safe and efficace, more research is needed to choose the best 3regimen for each patient.

6.
Int Med Case Rep J ; 17: 341-346, 2024.
Article de Anglais | MEDLINE | ID: mdl-38646456

RÉSUMÉ

This study aimed to optimize bowel preparation efficacy for colonoscopy in elderly constipation patients. A 71-year-old patient with chronic constipation and a history of poor bowel preparation. To address these challenges, we implemented a personalized strategy combining of PEG administration and walking exercise. The PEG was administered according to a protocol, with intermittent exercise breaks of 10 minute. Bowel cleanliness was assessed using the Boston Bowel Preparation Scale (BBPS). Adverse reactions and tolerance were closely monitored throughout the intervention. The patient's BBPS score improved from 3 to 8 post-intervention. The exercise intervention was well-tolerated (rating I), and mild nausea was observed only after the first PEG dose. No severe adverse reactions occurred. Subsequent Follow-up revealed symptom relief. The personalized approach combining (PEG and exercise intervention) successfully improved bowel preparation quality in the elderly constipation patient undergoing colonoscopy. This approach considers age-related changes in gastrointestinal function and activity level, offering an effective strategy to improve patient tolerance and reduce adverse reactions during bowel preparation. The findings underscore the importance of tailoring interventions for elderly constipation patients to optimize the colonoscopy experience.

7.
Toxics ; 12(4)2024 Mar 29.
Article de Anglais | MEDLINE | ID: mdl-38668477

RÉSUMÉ

Polyethylene (PE) is a common component of microplastic pollution, and cadmium (Cd) is a prevalent pollutant in contaminated freshwater bodies in China. Among cyanobacteria, Microcystis aeruginosa (M. aeruginosa) plays a crucial role in the formation of algal blooms in these water systems. However, there has been limited research on how microplastics and heavy metals affect cyanobacteria ecologically. This study aimed to evaluate the physiological effects of individual and combined exposure to Cd pollutants and microplastics on M. aeruginosa. The solutions containing 13 µm and 6.5 µm PE particles (100 mg/L) with Cd were used in the research. The results indicated that the combined treatment led to a significant inhibition of chlorophyll a content, dropping to zero by day 5. The treated groups exhibited higher microcystins (MCs) content compared to the control group, suggesting increased MCs release due to pollutant exposure. Interestingly, the adsorption of heavy metals by microplastics partially alleviated the toxicity of heavy metals on algal cells. Moreover, the combined treatment significantly suppressed catalase (CAT) activity compared to Cd treatment, indicating a synergistic effect that led to greater oxidative stress. Overall, this study provides valuable insights into the impact of PE and Cd pollution on freshwater ecosystems, elucidates the physiological responses of cyanobacteria to these pollutants, and establishes a theoretical groundwork for addressing complex water pollution using cyanobacteria-based strategies.

8.
Article de Anglais | MEDLINE | ID: mdl-38639902

RÉSUMÉ

This work has focused on the co-pyrolysis of sugarcane waste (SW) with polyethylene terephthalate (PET) to gain insight on its thermal decomposition, product distribution, kinetics, and synergistic effect. SW and PET were blended at different ratios (100:0, 80:20, 60:40, 40:60, and 0:100), and the Coats-Redfern method was used to determine the kinetics parameters. To ascertain the synergistic effect between SW and PET, product yields and composition of chemicals were compared with the synergistic effect of the individual components of pyrolysis. The bio-oil yield was significant at 60% of PET, with a difference of 19.41 wt% compared to the theoretical value. The synergistic impact of SW:PET on ester formation and acid compound inhibition was the most dominant at the 60:40 ratio. The kinetics analysis revealed that the diffusion mechanism, power law, and order of reactions were the most probable reaction models that can explain the pyrolysis of SW, and PET, and their blends. The resultant co-pyrolysis oil contained slightly larger hydrogen and carbon contents with low oxygen, and sulphur, and nitrogen contents, which improved the quality of the bio-oil. The results of this work could be used as a guide in selecting proper reaction conditions with optimal synergy during the co-pyrolysis process.

9.
Waste Manag ; 182: 91-101, 2024 Apr 20.
Article de Anglais | MEDLINE | ID: mdl-38643526

RÉSUMÉ

The recycling of polyethylene terephthalate (PET) stands as an effective strategy for mitigating plastic pollution and reducing resource waste. The study aimed to investigate the characterization and elimination efficiency of volatile organic compounds (VOCs) present in rPET at various recycling stages using comprehensive two-dimensional gas chromatography-quadrupole-time-of-flight-mass spectrometry coupled with chemometrics. The results revealed that 52, 135, 95, 44, and 33 VOCs, mostly classified into three chemical groups, were tentatively identified in virgin - PET (v-PET), cold water washed - rPET (C-rPET), decontaminated - rPET (D-rPET), melt-extruded - rPET (M-rPET), and solid-state polycondensation - rPET (S-rPET), respectively. Regarding the VOCs with high and median detection frequencies, fatty acyls showed the highest elimination efficiency (100 % and 92 %), followed by organooxygen compounds (81 % and 99 %), others (97 % and 95 %), and benzene and substituted derivatives (82 % and 95 %) in term of HS-SPME. Following the recycling process, there was a general decrease in the concentration of almost all VOCs, as evidenced by the substantial reduction of o-Xylene, hexanoic acid, octanal, and D-limonene from 18.11, 22.43, 30.74, and 7.41 mg/kg to 0, 0, 3.97, and 0 mg/kg, respectively. However, it was noteworthy that the VOCs identified in the samples were not completely extracted, owing to the limitations of HS-SPME. Furthermore, chemometrics analysis indicated significant discrimination among VOCs from vPET, C-rPET, D-rPET, and M-rPET, while indistinct differences were observed between M-rPET and S-rPET. This study contributes to the enhancement of the recycling process and emphasizes the importance of safeguarding consumer health in terms of elimination of VOCs.

10.
Article de Anglais | MEDLINE | ID: mdl-38644425

RÉSUMÉ

The ubiquitous proximity of the commonly used microplastic (MP) particles particularly polyethylene (PE), polypropylene (PP), and polystyrene (PS) poses a serious threat to the environment and human health globally. Biological treatment as an environment-friendly approach to counter MP pollution has recent interest when the bio-agent has beneficial functions in their ecosystem. This study aimed to utilize beneficial floc-forming bacteria Bacillus cereus SHBF2 isolated from an aquaculture farm in reducing the MP particles (PE, PP, and PS) from their environment. The bacteria were inoculated for 60 days in a medium containing MP particle as a sole carbon source. On different days of incubation (DOI), the bacterial growth analysis was monitored and the MP particles were harvested to examine their weight loss, surface changes, and alterations in chemical properties. After 60 DOI, the highest weight loss was recorded for PE, 6.87 ± 0.92%, which was further evaluated to daily reduction rate (k), 0.00118 day-1, and half-life (t1/2), 605.08 ± 138.52 days. The OD value (1.74 ± 0.008 Abs.) indicated the higher efficiency of bacteria for PP utilization, and so for the colony formation per define volume (1.04 × 1011 CFU/mL). Biofilm formation, erosions, cracks, and fragments were evident during the observation of the tested MPs using the scanning electron microscope (SEM). The formation of carbonyl and alcohol group due to the oxidation and hydrolysis by SHBF2 strain were confirmed using the Fourier transform infrared spectroscopic (FTIR) analysis. Additionally, the alterations of pH and CO2 evolution from each of the MP type ensures the bacterial activity and mineralization of the MP particles. The findings of this study have confirmed and indicated a higher degree of biodegradation for all of the selected MP particles. B. cereus SHBF2, the floc-forming bacteria used in aquaculture, has demonstrated a great potential for use as an efficient MP-degrading bacterium in the biofloc farming system in the near future to guarantee a sustainable green aquaculture production.

11.
Environ Sci Technol ; 58(15): 6772-6780, 2024 Apr 16.
Article de Anglais | MEDLINE | ID: mdl-38577774

RÉSUMÉ

The quality of chemical analysis is an important aspect of passive sampling-based environmental assessments. The present study reports on a proficiency testing program for the chemical analysis of hydrophobic organic compounds in silicone and low-density polyethylene (LDPE) passive samplers and hydrophilic compounds in polar organic chemical integrative samplers. The median between-laboratory coefficients of variation (CVs) of hydrophobic compound concentrations in the polymer phase were 33% (silicone) and 38% (LDPE), similar to the CVs obtained in four earlier rounds of this program. The median CV over all rounds was 32%. Much higher variabilities were observed for hydrophilic compound concentrations in the sorbent: 50% for the untransformed data and a factor of 1.6 after log transformation. Limiting the data to the best performing laboratories did not result in less variability. Data quality for hydrophilic compounds was only weakly related to the use of structurally identical internal standards and was unrelated to the choice of extraction solvent and extraction time. Standard deviations of the aqueous concentration estimates for hydrophobic compound sampling by the best performing laboratories were 0.21 log units for silicone and 0.27 log units for LDPE (factors of 1.6 to 1.9). The implications are that proficiency testing programs may give more realistic estimates of uncertainties in chemical analysis than within-laboratory quality control programs and that these high uncertainties should be taken into account in environmental assessments.


Sujet(s)
Polyéthylène , Polluants chimiques de l'eau , Polyéthylène/analyse , Polluants chimiques de l'eau/analyse , Surveillance de l'environnement/méthodes , Composés chimiques organiques , Silicone
12.
Comp Biochem Physiol C Toxicol Pharmacol ; 281: 109917, 2024 Apr 06.
Article de Anglais | MEDLINE | ID: mdl-38583695

RÉSUMÉ

Human activities have directly impacted the environment, causing significant ecological imbalances. From the different contaminants resulting from human activities, plastics are of major environmental concern. Due to their high use and consequent discharge, plastics tend to accumulate in aquatic environments. There, plastics can form smaller particles (microplastics, MPs), due to fragmentation and weathering, which are more prone to interact with aquatic organisms and cause deleterious effects, including at the basis of different food webs. This study assessed the effects of two microplastics (polyethylene terephthalate, PET; and polypropylene, PP; both of common domestic use) in the freshwater cladoceran species Daphnia magna. Toxic effects were assessed by measuring reproductive traits (first brood and total number of offspring), and activities of biomarkers involved in xenobiotic metabolism (phase I: cytochrome P-450 isoenzymes CYP1A1, 1A2 and 3A4; phase II/conjugation: glutathione S-transferases; and antioxidant defense (catalase)). Both MPs showed a potential to significantly reduce reproductive parameters in D. magna. Furthermore, PET caused a significant increase in some isoenzymes of CYP450 in acutely exposed organisms, but this effect was not observed in chronically exposed animals. Similarly, the activity of the antioxidant defense (CAT) was significantly increased in acutely exposed animals, but not in chronically exposed organisms. This pattern of effects suggests a possible mechanism of long-term adaptation to the presence of the tested MPs. In conclusion, the herein tested MPs have shown the potential to induce deleterious effects on D. magna mainly observed in terms of the reproductive outcomes. Changes at the biochemical level seems transient and are not likely to occur in long term, environmentally exposed crustaceans.

13.
Adv Sci (Weinh) ; : e2403002, 2024 Apr 16.
Article de Anglais | MEDLINE | ID: mdl-38626364

RÉSUMÉ

Polyester plastics, constituting over 10% of the total plastic production, are widely used in packaging, fiber, single-use beverage bottles, etc. However, their current depolymerization processes face challenges such as non-broad spectrum recyclability, lack of diversified high-value-added depolymerization products, and crucially high energy consumption. Herein, an efficient strategy is developed for dismantling the compact structure of polyester plastics to achieve diverse monomer recovery. Polyester plastics undergo swelling and decrystallization with a low depolymerization energy barrier via synergistic effects of polyfluorine/hydrogen bonding, which is further demonstrated via density functional theory calculations. The swelling process is elucidated through scanning electron microscopy analysis. Obvious destruction of the crystalline region is demonstrated through X-ray crystal diffractometry curves. PET undergoes different aminolysis efficiently, yielding nine corresponding high-value-added monomers via low-energy upcycling. Furthermore, four types of polyester plastics and five types of blended polyester plastics are closed-loop recycled, affording diverse monomers with exceeding 90% yields. Kilogram-scale depolymerization of real polyethylene terephthalate (PET) waste plastics is successfully achieved with a 96% yield.

14.
Macromol Rapid Commun ; : e2400064, 2024 Apr 09.
Article de Anglais | MEDLINE | ID: mdl-38594967

RÉSUMÉ

Polyethylene (PE), a highly prevalent non-biodegradable polymer in the field of plastics, presents a waste management issue. To alleviate this issue, bio-based PE (bio-PE), derived from renewable resources like corn and sugarcane, offers an environmentally friendly alternative. This review discusses various production methods of bio-PE, including fermentation, gasification, and catalytic conversion of biomass. Interestingly, the bio-PE production volumes and market are expanding due to the growing environmental concerns and regulatory pressures. Additionally, the production of PE and bio-PE biocomposites using agricultural waste as filler materials, highlights the growing demand for sustainable alternatives to conventional plastics. According to previous studies, addition of ≈50% defibrillated corn and abaca fibers into bio-PE matrix and a compatibilizer, results in the highest Young's modulus of 4.61 and 5.81 GPa, respectively. These biocomposites have potential applications in automotive, building construction, and furniture industries. Moreover, the advancement made in abiotic and biotic degradation of PE and PE biocomposites is elucidated to address their environmental impacts. Finally, the paper concludes with insights into the opportunities, challenges, and future perspectives in the sustainable production and utilization of PE and bio-PE biocomposites. In summary, production of PE and bio-PE biocomposites can contribute to a cleaner and sustainable future.

15.
J Contam Hydrol ; 263: 104339, 2024 Mar 27.
Article de Anglais | MEDLINE | ID: mdl-38564944

RÉSUMÉ

Plastic particles, measuring <5 mm in size, mainly originate from larger plastic debris undergoing degradation, fragmenting into even smaller fragments. The goal was to analyze the spatial diversity and polymer composition of microplastics (MPs) in North Chennai, South India, aiming to evaluate their prevalence and features like composition, dimensions, color, and shape. In 60 sediment samples, a combined count of 1589 particles were detected, averaging 26 particles per 5 g-1 of dry sediment. The water samples from the North Chennai vicinity encompassed a sum of 1588 particles across 71 samples, with an average of 22 items/L. The majority of MPs ranged in size from 1 mm to 500 µm. The ATR-FTIR results identified the predominant types of MPs as polystyrene, polyvinyl chloride, polyethylene, polyethylene terephthalate, and polypropylene in sediment and water. The spatial variation analysis revealed high MPs concentration in landfill sites, areas with dense populations, and popular tourist destinations. The pollution load index in water demonstrated that MPs had contaminated all stations. Upon evaluating the polymeric and pollution risks, it was evident that they ranged from 5.13 to 430.15 and 2.83 to 15,963.2, which is relatively low to exceedingly high levels. As the quantity of MPs and hazardous polymers increased, the level of pollution and corresponding risks also escalated significantly. The existence of MPs in lake water, as opposed to open well water, could potentially pose a cancer risk for both children and adults who consume it. Detecting MPs in water samples highlights the significance of implementing precautionary actions to alleviate the potential health hazards they create.

16.
Int J Biol Macromol ; 266(Pt 2): 131249, 2024 Apr 02.
Article de Anglais | MEDLINE | ID: mdl-38569998

RÉSUMÉ

This study investigated the development of biodegradable films made from a combination of polyethylene glycol (PEG), carboxymethyl cellulose (CMC) and mixtures from natamycin and ferulic acid. The films were characterized for their surface microstructure, antioxidant activity, thermal stability, mechanical properties, permeability and antifungal/bacterial activity. The addition of natamycin and ferulic acid to the film matrix enhanced antioxidant activity, thermal stability, antimicrobial activity, reduced the water vapor permeability (WVP) to 1.083 × 10-10 g × m-1s-1Pa-1, imparted opaque color and increased opacity up to 3.131 A mm-1. The attendance of natamycin and ferulic acid inside films created a clear roughness shape with agglomerates on the surface of films and caused a clear inhibition zone for Aspergillus niger, E. coli and C. botulinum. The utilization of PG/CMC/N-F packaging material on Ras cheese had a noticeable effect, resulting in a slight decrease in moisture content from 34.23 to 29.17 %. Additionally, it helped maintain the titrable acidity within the range of 0.99 % to 1.11 % and the force required for puncture from 0.035 to 0.052 N with non-significant differences. Importantly, these changes did not significantly affect the sensory qualities of Ras cheese during the storage period.

17.
Anal Chim Acta ; 1302: 342487, 2024 May 08.
Article de Anglais | MEDLINE | ID: mdl-38580405

RÉSUMÉ

BACKGROUND: Many of the chemicals frequently used as additives have been recognised as hazardous substances, and therefore their analysis is necessary to evaluate plastic contamination risk. Additives analysis in plastic samples is usually performed by methods involving high volumes of toxic solvents or having high detection limits. In this work, a novel, fast, solventless and reliable green method was developed for the automated analysis of plastic additives from plastic samples. The proposed method consists of in-tube extraction dynamic headspace sampling (ITEX-DHS) combined with gas chromatography (GC) and mass spectrometry (MS/MS) determination. RESULTS: Several parameters affecting the ITEX-DHS extraction of 47 additives in plastic samples (including phthalates, bisphenols, adipates, citrates, benzophenones, organophosphorus compounds, among others) were optimised. The use of matrix-matched calibration, together with labelled surrogate standards, minimises matrix effects, resulting in recoveries between 70 and 128%, with good quantitation limits (below 0.1 µg g-1 for most compounds) and precision (<20%). The method proposed can be applied to any type of polymer, but due to the existence of the matrix effect, calibrates with the adequate matrix should be performed for each polymer. SIGNIFICANCE: This method represents an effective improvement compared to previous methods because it is fast, solvent-free, fully automated, and provides reliable quantification of additives in plastic samples.

18.
G3 (Bethesda) ; 2024 Apr 02.
Article de Anglais | MEDLINE | ID: mdl-38564250

RÉSUMÉ

Galleria mellonella is a pest of honeybees in many countries because its larvae feed on beeswax. However, G. mellonella larvae can also eat various plastics, including polyethylene, polystyrene and polypropylene, so the species is garnering increasing interest as a tool for plastic biodegradation research. This paper presents an improved genome (99.3% completed lepidoptera_odb10 BUSCO; genome mode) for G. mellonella. This 472 Mb genome is in 221 contigs with an N50 of 6.4 MB and contains 13,604 protein-coding genes. Genes that code for known and putative polyethylene-degrading enzymes and their similarity to proteins found in other Lepidoptera are highlighted. An analysis of secretory proteins more likely to be involved in the plastic catabolic process has also been carried out.

19.
Adv Mater ; : e2311634, 2024 Apr 24.
Article de Anglais | MEDLINE | ID: mdl-38657970

RÉSUMÉ

Nucleic acid amplification, the bedrock of biotechnology and molecular diagnostics, surges in applications-especially isothermal approaches-heightening the demand for advanced and precisely engineered methods. Here, we present a novel approach for Amplifying DNA with Multi-arm Priming and Looping Optimization of Nucleic Acid (AMPLON). AMPLON relied on a novel polymeric material that utilizes a unique set of multi-arm polyethylene glycol-DNA primers for efficient DNA amplification under isothermal conditions. Each arm carries ssDNA complementing the sense or antisense sequence of the target DNA (n = 6; 50% sense to 50% antisense sequences). The amplification reaction begins with antisense arms binding to the target DNA, forming a template for sense-carrying arms to direct multi-arm large DNA amplicon synthesis through successive DNA looping and unlooping steps. The developed AMPLON enables highly specific and sensitive detection of the targeted nucleic acid sequence. Using HIV-1 as a model clinical target, AMPLON exhibited high sensitivity, detecting target concentrations as low as 100 copies/mL, and selectively amplifying HIV-1 in the presence of other DNA and RNA viruses, such as HBV and HCV. Compared to a quantitative real-time PCR (qRT-PCR) assay using sensitive primers, AMPLON reliably identifies HIV-1 RNA in plasma samples (n = 20) with a significant agreement rate of 95%. With its ability to achieve highly specific and sensitive target amplification within 30 minutes, AMPLON holds immense potential to transform the field of nucleic acid research and unleashing new possibilities in medicine and biotechnology. This article is protected by copyright. All rights reserved.

20.
Article de Anglais | MEDLINE | ID: mdl-38659385

RÉSUMÉ

Here, an artificial intelligence (AI)-based approach was employed to optimize the production of electrospun scaffolds for in vivo wound healing applications. By combining polycaprolactone (PCL) and poly(ethylene glycol) (PEG) in various concentration ratios, dissolved in chloroform (CHCl3) and dimethylformamide (DMF), 125 different polymer combinations were created. From these polymer combinations, electrospun nanofiber meshes were produced and characterized structurally and mechanically via microscopic techniques, including chemical composition and fiber diameter determination. Subsequently, these data were used to train a neural network, creating an AI model to predict the optimal scaffold production solution. Guided by the predictions and experimental outcomes of the AI model, the most promising scaffold for further in vitro analyses was identified. Moreover, we enriched this selected polymer combination by incorporating antibiotics, aiming to develop electrospun nanofiber scaffolds tailored for in vivo wound healing applications. Our study underscores three noteworthy conclusions: (i) the application of AI is pivotal in the fields of material and biomedical sciences, (ii) our methodology provides an effective blueprint for the initial screening of biomedical materials, and (iii) electrospun PCL/PEG antibiotic-bearing scaffolds exhibit outstanding results in promoting neoangiogenesis and facilitating in vivo wound treatment.

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