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1.
Sci Rep ; 14(1): 16468, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39013981

RESUMO

This study explores the optimization of iron electrocoagulation for treating laundry greywater, which accounts for up to 38% of domestic greywater. Characterized by high concentrations of surfactants, detergents, and suspended solids, laundry greywater presents complex challenges for treatment processes, posing significant environmental and health risks. Utilizing response surface methodology (RSM), this research developed a second-order polynomial regression model focused on key operational parameters such as the area-to-volume ratio (A/V), current density, electrolysis time, and settling time. Optimal treatment conditions were identified: an A/V ratio of 30 m2/m3, a current density of 10 mA/cm2, an electrolysis duration of 50 min, and a settlement period of 12 h. Under these conditions, exceptional treatment outcomes were achieved, with turbidity removal reaching 94.26% and COD removal at 99.64%. The model exhibited high effectiveness for turbidity removal, with an R2 value of 94.16%, and moderate effectiveness for COD removal, with an R2 value of 75.90%. The interaction between the A/V ratio and electrolysis time particularly underscored their critical role in electrocoagulation system design. Moreover, these results highlight the potential for optimizing electrocoagulation parameters to adapt to daily fluctuations in greywater production and meet specific household reuse needs, such as toilet flushing. This tailored approach aims to maximize contaminant separation and coagulant efficiency, balance energy use and operational costs, and contribute to sustainable water management.

2.
Ther Deliv ; 15(6): 427-447, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38722230

RESUMO

Aim: This study aimed to formulate erlotinib hydrochloride (ERT-HCL)-loaded chitosan (CS) and poly (lactic-co-glycolic acid) (PLGA) nanoparticles (NPs) using Quality-by-Design (QbD) to optimize critical quality attributes (CQAs). Materials & methods: Quality target product profile (QTPP) and CQAs were initially established. Based on L8-Taguchi screening and risk assessments, central composite design (CCD) design was used to optimize NPs. Results: ERT-HCL-loaded CS-PLGA NPs had a mean particle diameter, zeta potential and entrapment efficiency of 226.50 ± 1.62 d.nm, 27.66 ± 0.64 mV and 78.93 ± 1.94 %w/w, respectively. The NPs exhibited homogenous spherical morphology and sustained release for 72 h. Conclusion: Using systematic QbD approach, ERT-HCL was encapsulated in CS-PLGA NPs, optimizing CQAs. These findings propel future research for improved NSCLC treatment.


Innovative erlotinib-loaded chitosan-PLGA nanoparticles, developed through a systematic QbD approach, promise enhanced drug delivery for NSCLC. Optimized for size, potential and entrapment efficiency, these particles demonstrate sustained release over 72 h. #DrugDelivery #QBD #NSCLC.


Assuntos
Quitosana , Cloridrato de Erlotinib , Ácido Láctico , Nanopartículas , Tamanho da Partícula , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Cloridrato de Erlotinib/administração & dosagem , Cloridrato de Erlotinib/química , Quitosana/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Nanopartículas/química , Ácido Láctico/química , Ácido Poliglicólico/química , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Química Farmacêutica/métodos , Preparações de Ação Retardada , Antineoplásicos/administração & dosagem , Antineoplásicos/química
3.
Heliyon ; 10(7): e28913, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38596064

RESUMO

Magnesium phosphate cement (MPC) is a high-performance repairing material suitable for the interfacial disease of slab track. In this study, the early properties of MPC were optimized using central composite design (CCD) approach based on response surface methodology (RSM). Three factors with five levels and three responses were considered. The significance of the factors and their interactions were verified by using analysis of variance (ANOVA). The result show that the mass ratio of water-to-binder (W/b) affects fluidity, while the mass ratio of magnesia-to-phosphate (M/P) and borax-to-magnesia (B/M) impact the setting time of MPC. Higher W/b results in higher fluidity, while an increase in M/P reduces the setting time by increasing the neutralization reaction. Borax addition retards the reaction, prolonging the setting time. The three factors significantly affect the early compressive strength of MPC. At M/P = 3.5, the interweaving of MgO and K-struvite (MKP) forms a dense network structure, enhancing the strength. Borax and W/b interact to affect compressive strength, with borax retarding MKP crystal growth and higher W/b reducing compactness. Combined with microscopic property test, the strength generation mechanism of MPC with optimized mixing ratio was revealed, And the feasibility of field application of MPC was verified by strength test.

4.
Artigo em Inglês | MEDLINE | ID: mdl-38658186

RESUMO

Lactobacillus paracasei IMC502® is a commercially successful probiotic strain. However, there are no reports that investigate growth medium composition in relation to improved biomass production for this strain. The major outcome of the present study is the design and optimization of a growth medium based on vegan components to be used in the cultivation of Lactobacillus paracasei IMC502®, by using Design of Experiments. Besides comparing different carbon sources, the use of plant-based peptones as nitrogen sources was considered. In particular, the use of guar peptone as the main nitrogen source, in the optimization of fermentation media for the production of probiotics, could replace other plant peptones (e.g. potato, rice, wheat, and soy) which are part of the human diet, thereby avoiding an increase in product and process prices. A model with R2 and adjusted R2 values higher than 95% was obtained. Model accuracy was equal to 94.11%. The vegan-optimized culture medium described in this study increased biomass production by about 65% compared to growth on De Man-Rogosa-Sharpe (MRS) medium. Moreover, this approach showed that most of the salts and trace elements generally present in MRS are not affecting biomass production, thus a simplified medium preparation can be proposed with higher probiotic biomass yield and titer. The possibility to obtain viable lactic acid bacteria at high density from vegetable derived nutrients will be of great interest to specific consumer communities, opening the way to follow this approach with other probiotics of impact for human health.


Assuntos
Meios de Cultura , Fermentação , Lacticaseibacillus paracasei , Probióticos , Meios de Cultura/química , Probióticos/metabolismo , Lacticaseibacillus paracasei/metabolismo , Lacticaseibacillus paracasei/crescimento & desenvolvimento , Biomassa , Nitrogênio/metabolismo , Peptonas/metabolismo , Carbono/metabolismo
5.
Sci Rep ; 14(1): 9412, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38658625

RESUMO

Textile industry dye effluent contains a mixture of different kinds of dyes. Many times, photocatalysis is targeted as a solution for the treatment of dye effluent from the textile industry. Many researches have been published related to the photocatalysis of single textile dyes but in the real-world scenario, effluent is a mixture of dyes. Magnesium oxide (MgO) is used as a photocatalyst to treat a mixture (binary solution) of Methylene blue (MB) and Methylene violet (MV) along with individual MB and MV dyes in this article. MgO shows remarkable photocatalytic activity at about 93 and 88% for MB and MV dye in binary solution within 135 min. Furthermore, to study the influence of process parameters, experiments are designed with the help of the central composite design (CCD), and Response surface methodology (RSM) is used to study the interactions between parameters. For this study, five parameters are selected i.e., Photocatalyst dosage, initial concentration of both dyes, time of exposure to the light source, and pH of the binary solution. The photocatalytic process is also optimized and finally optimization of process parameters is validated with an experiment. The result of the validation experiment is very close to the predicted photocatalytic activity.

6.
Bull Environ Contam Toxicol ; 112(3): 48, 2024 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-38459992

RESUMO

This study aimed on the development of a SPE-UHPLC-MS/MS method for the simultaneous determination of pesticide residues in drinking water samples. A chemometric approach was applied to optimize the efficiency of the SPE pretreatment procedure. This study involved (i) the application of a Full Factorial Design for the screening of the significant factors, (ii) the application of a Central Composite Design for the determination of the optimal conditions and (iii) the evaluation and validation of the significance of the statistically proposed models. Oasis HLB cartridges were used for the extraction. The optimum sample volume was 300 mL and the elution solvent 3 mL of the mixture of methanol:ethylacetate 70:30 v/v. The method was validated according to the international guidelines. Recoveries were ranged from 63 to 116% and the detection limits were between 0.1 and 1.5 pg mL- 1. The validated method could be used in routine analysis for pesticides screening.


Assuntos
Praguicidas , Praguicidas/análise , Espectrometria de Massas em Tandem/métodos , Cromatografia Líquida de Alta Pressão/métodos , Quimiometria , Extração em Fase Sólida/métodos , Água
7.
World J Microbiol Biotechnol ; 40(3): 91, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38345638

RESUMO

α-Galactosidase is an important exoglycosidase belonging to the hydrolase class of enzymes, which has therapeutic and industrial potential. It plays a crucial role in hydrolyzing α-1,6 linked terminal galacto-oligosaccharide residues such as melibiose, raffinose, and branched polysaccharides such as galacto-glucomannans and galactomannans. In this study, Actinoplanes utahensis B1 was explored for α-galactosidase production, yield improvement, and activity enhancement by purification. Initially, nine media components were screened using the Plackett-Burman design (PBD). Among these components, sucrose, soya bean flour, and sodium glutamate were identified as the best-supporting nutrients for the highest enzyme secretion by A. Utahensis B1. Later, the Central Composite Design (CCD) was implemented to fine-tune the optimization of these components. Based on sequential statistical optimization methodologies, a significant, 3.64-fold increase in α-galactosidase production, from 16 to 58.37 U/mL was achieved. The enzyme was purified by ultrafiltration-I followed by multimode chromatography and ultrafiltration-II. The purity of the enzyme was confirmed by Sodium Dodecyl Sulphate-Polyacrylamide Agarose Gel Electrophoresis (SDS-PAGE) which revealed a single distinctive band with a molecular weight of approximately 72 kDa. Additionally, it was determined that this process resulted in a 2.03-fold increase in purity. The purified α-galactosidase showed an activity of 2304 U/mL with a specific activity of 288 U/mg. This study demonstrates the isolation of Actinoplanes utahensis B1 and optimization of the process for the α-galactosidase production as well as single-step purification.


Assuntos
Actinoplanes , Oligossacarídeos , alfa-Galactosidase , alfa-Galactosidase/química , Peso Molecular , Concentração de Íons de Hidrogênio
8.
Biomed Chromatogr ; 38(3): e5812, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38228470

RESUMO

A systematic and novel quality by design-enabled, rapid, simple, and economic stability-indicating HPLC method for quantifying nirmatrelvir (NMT) was successfully developed and validated. An analytical target profile (ATP) was established, and critical analytical attributes (CAAs) were allocated to meet the ATP requirements. The method used chromatographic separation using a Purosphere column with a 4.6 mm inner diameter × 250 mm (2.5 µm). The analysis occurred at 50°C with a flow rate of 1.2 mL/min and detection at 220 nm. A 10 µL sample was injected, and the mobile phase consisted of two components: mobile phase A, containing 0.1% formic acid in water (20%), and mobile phase B, containing 0.1% formic acid in acetonitrile (80%). The diluent was prepared by mixing acetonitrile and water at a 90:10 v/v ratio. The retention time for the analyte was determined to be 2.78 min. Accuracy exceeded 99%, and the correlation coefficient was greater than 0.999. The validated HPLC method was characterized as precise, accurate, and robust. Significantly, NMT was found to be susceptible to alkaline, acidic, and peroxide conditions during forced degradation testing. The stability-indicating method developed effectively separated the degradation products formed during stress testing, underlining its effectiveness in stability testing and offering accuracy, reliability, and sensitivity in determining NMT.


Assuntos
Trifosfato de Adenosina , Formiatos , Água , Cromatografia Líquida de Alta Pressão/métodos , Reprodutibilidade dos Testes , Estabilidade de Medicamentos , Acetonitrilas , Preparações Farmacêuticas
9.
Int J Phytoremediation ; 26(1): 98-113, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37390844

RESUMO

The applicability of Zeolitic Imidazolate-67, Modified by Fe3O4 Nanoparticles, was studied for removing textile dye Reactive yellow 105 from wastewater by adsorption method using response surface methodology (RSM). For the adsorption characterization of the adsorbent used in HE-4G dye adsorption, BET, FTIR, XRD, and SEM analyses were performed. The impacts of variables, including initial HE-4G dye concentration (X1), pH (X2), adsorbent dosage (X3), and sonication time (X4), the highest removal efficiency as 98%, 10 mg/L initial concentration, pH 6, 0.025 g adsorbent dosage, and 6.0 min time respectively. Adsorption equilibrium and kinetic data it, that data were for the Langmuir isotherm, pseudo-second-order kinetics, and maximum adsorption capacity (105.0 mg/g), respectively. Thermodynamic parameters indicated HE-4G dye adsorption is feasible, spontaneous and exothermic. Promising treatment capabilities of the ZIF-67-Fe3O4NPs have been during the comparative adsorption removal of HE-4G dye from DI water against spiked natural water samples and synthetic Na+, K+, Ca2+, and Mg2+ solutions. The observed outcome is the suitability of the artificial neural network model as a tool for mean square error, (MSEANN = 0.53, and R2 = 0.9926) for removing HE-4G dye. Results that ZIF-67-Fe3O4NPs, like being recyclable, and cost-efficient made it a promising absorbent for wastewater.


Assuntos
Nanopartículas , Poluentes Químicos da Água , Purificação da Água , Zeolitas , Águas Residuárias , Purificação da Água/métodos , Biodegradação Ambiental , Redes Neurais de Computação , Água/análise , Têxteis , Adsorção , Cinética , Poluentes Químicos da Água/química , Concentração de Íons de Hidrogênio
10.
Microorganisms ; 11(12)2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-38137979

RESUMO

Fungal infections currently pose a real threat to human lives. In the current study, soil bacterial isolates were screened for the production of antifungal compounds to combat human fungal pathogens. Notably, the bacterial F1 isolate exhibited antimycotic action towards the Candida albicans ATCC 10231 and Aspergillus niger clinical isolates. By employing phenotypic and molecular techniques, we identified the F1 isolate as the Bacillus toyonensis isolate OQ071612. The purified extract showed stability within a pH range of 6-7 and at temperatures of up to 50 °C. It demonstrated potential antifungal activity in the presence of various surfactants, detergents, and enzymes. The purified extract was identified as 6-methoxy-1H-Indole-2-carboxylic acid using advanced spectroscopic techniques. To optimize the antifungal metabolite production, we utilized response surface methodology (RSM) with a face-centered central composite design, considering nutritional and environmental variables. The optimal conditions were as follows: starch (5 g/L), peptone (5 g/L), agitation rate of 150 rpm, pH 6, and 40 °C temperature. A confirmatory experiment validated the accuracy of the optimization process, resulting in an approximately 3.49-fold increase in production. This is the first documented report on the production and characterization of 6-methoxy-1H-Indole-2-carboxylic acid (MICA) antifungal metabolite from Bacillus toyonensis.

11.
Polymers (Basel) ; 15(19)2023 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-37836023

RESUMO

Additive manufacturing using continuous carbon-fibre-reinforced polymer (CCFRP) presents an opportunity to create high-strength parts suitable for aerospace, engineering, and other industries. Continuous fibres reinforce the load-bearing path, enhancing the mechanical properties of these parts. However, the existing additive manufacturing processes for CCFRP parts have numerous disadvantages. Resin- and extrusion-based processes require time-consuming and costly post-processing to remove the support structures, severely restricting the design flexibility. Additionally, the production of small batches demands considerable effort. In contrast, laser sintering has emerged as a promising alternative in industry. It enables the creation of robust parts without needing support structures, offering efficiency and cost-effectiveness in producing single units or small batches. Utilising an innovative laser-sintering machine equipped with automated continuous fibre integration, this study aims to merge the benefits of laser-sintering technology with the advantages of continuous fibres. The paper provides an outline, using a finite element model in COMSOL Multiphysics, for simulating and identifying an optimised operating point range for the automated integration of continuous fibres. The results demonstrate a remarkable reduction in processing time of 233% for the fibre integration and a reduction of 56% for the width and 44% for the depth of the heat-affected zone compared to the initial setup.

12.
Polymers (Basel) ; 15(18)2023 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-37765702

RESUMO

In this study, a novel technique is introduced that involves the combination of an ion-imprinted polymer and solid-phase extraction to selectively adsorb lithium ions from reverse osmosis brine. In the process of synthesizing ion-imprinted polymers, phthalocyanine acrylate acted as the functional monomer responsible for lithium chelation. The structural and morphological characteristics of the molecularly imprinted polymers and non-imprinted polymers were assessed using Fourier transform infrared spectroscopy and scanning electron microscopy. The adsorption data for Li on an ion-imprinted polymer showed an excellent fit to the Langmuir isotherm, with a maximum adsorption capacity (Qm) of 3.2 mg·g-1. Comprehensive chemical analyses revealed a significant Li concentration with a higher value of 45.36 mg/L. Through the implementation of a central composite design approach, the adsorption and desorption procedures were systematically optimized by varying the pH, temperature, sorbent mass, and elution volume. This systematic approach allowed the identification of the most efficient operating conditions for extracting lithium from seawater reverse osmosis brine using ion-imprinted polymer-solid-phase extraction. The optimum operating conditions for the highest efficiency of adsorbing Li+ were determined to be a pH of 8.49 and a temperature of 45.5 °C. The efficiency of ion-imprinted polymer regeneration was evaluated through a cycle of the adsorption-desorption process, which resulted in Li recoveries of up to 80%. The recovery of Li from the spiked brine sample obtained from the desalination plant reverse osmosis waste through the ion-imprinted polymer ranged from 62.8% to 71.53%.

13.
Microb Cell Fact ; 22(1): 176, 2023 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-37679768

RESUMO

BACKGROUND: Bioemulsifiers are natural or microbial-based products with the ability to emulsify hydrophobic compounds in water. These compounds are biodegradable, eco-friendly, and find applications in various industries. RESULTS: Thirteen yeasts were isolated from different sources in Alexandria, Egypt, and evaluated for their potential to produce intracellular bioemulsifiers. One yeast, isolated from a local market in Egypt, showed the highest emulsification index (EI24) value. Through 26S rRNA sequencing, this yeast was identified as Saccharomyces cerevisiae strain MYN04. The growth kinetics of the isolate were studied, and after 36 h of incubation, the highest yield of cell dry weight (CDW) was obtained at 3.17 g/L, with an EI24 of 55.6%. Experimental designs were used to investigate the effects of culture parameters on maximizing bioemulsifier SC04 production and CDW. The study achieved a maximum EI24 of 79.0 ± 2.0%. Furthermore, the crude bioemulsifier was precipitated with 50% ethanol and purified using Sephadex G-75 gel filtration chromatography. Bioemulsifier SC04 was found to consist of 27.1% carbohydrates and 72.9% proteins. Structural determination of purified bioemulsifier SC04 was carried out using Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDX), high-performance liquid chromatography (HPLC), and nuclear magnetic resonance spectroscopy (NMR). FTIR spectroscopy revealed characteristic bands associated with carboxyl and hydroxyl groups of carbohydrates, as well as amine groups of proteins. HPLC analysis of monosaccharide composition detected the presence of mannose, galactose, and glucose. Physicochemical characterization of the fraction after gel filtration indicated that bioemulsifier SC04 is a high molecular weight protein-oligosaccharide complex. This bioemulsifier demonstrated stability at different pH values, temperatures, and salinities. At a concentration of 0.5 mg/mL, it exhibited 51.8% scavenging of DPPH radicals. Furthermore, in vitro cytotoxicity evaluation using the MTT assay revealed a noncytotoxic effect of SC04 against normal epithelial kidney cell lines. CONCLUSIONS: This study presents a new eco-friendly bioemulsifier, named SC04, which exhibits significant emulsifying ability, antioxidant and anticancer properties, and stabilizing properties. These findings suggest that SC04 is a promising candidate for applications in the food, pharmaceutical, and industrial sectors.


Assuntos
Antioxidantes , Saccharomyces cerevisiae , Linhagem Celular , Cromatografia em Gel , Galactose
14.
Polymers (Basel) ; 15(15)2023 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-37571173

RESUMO

Styrene, a chemical widely used in various industries, undergoes metabolic breakdown in the human body, resulting in the production of phenylglyoxylic acid (PGA). A novel molecularly imprinted polymer (MIP) was synthesised for selective extraction and enrichment of PGA in urine samples prior to high-performance liquid chromatography. The MIP employed in this research was a 4-vinylpyridine molecularly imprinted polymer (4-VPMIP) prepared via mass polymerisation using a noncovalent method. The structural and morphological characteristics of the molecularly imprinted polymers (MIPs) and non-imprinted polymers (NIPs) were evaluated using Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM). The efficiency of the molecularly imprinted solid-phase extraction (MISPE) process was optimised by investigating critical variables such as sample pH, sorbent mass, sample flow rate, and volume of the elution solvent. A central composite design (CCD) within the response surface methodology was utilised to develop separate models for the adsorption and desorption steps. Analysis of variance (ANOVA) confirmed the excellent fit of the experimental data to the proposed response models. Under the optimised conditions, the molecularly imprinted polymers exhibited a higher degree of selectivity and affinity for PGA, with a relative selectivity coefficient (α) of 2.79 against hippuric acid. The limits of detection (LOD) and quantification (LOQ) for PGA were determined to be 0.5 mg/L and 1.6 mg/L, respectively. The recoveries of PGA ranged from 97.32% to 99.06%, with a relative standard deviation (RSD) lower than 4.6%. Furthermore, MIP(4VP)SPE demonstrated the potential for recycling up to three times without significant loss in analyte recovery.

15.
Nanomedicine (Lond) ; 18(14): 963-985, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37503870

RESUMO

Background: Melanoma is the most aggressive and deadly form of skin cancer. The stratum corneum of the skin is a major obstacle to dermal and transdermal drug delivery. Ultradeformable nanovesicular transferosome has the capacity for deeper skin penetration and its incorporation into hydrogel forms a transgelosome that has better skin permeability and patient compliance. Method: Here, the quality-by-design-based development and optimization of nanovesicular transgelosome of standardized Piper longum fruit ethanolic extract (PLFEE) for melanoma therapy are reported. Results: Compared with standardized PLFEE-loaded plain gel, the transgelosome displayed optimal pharmaceutical properties and improved ex vivo skin permeability and in vivo tumor regression in B16F10 melanoma-bearing C57BL/6 mice. Conclusion: The results reflect the potential of transgelosome for melanoma therapy.


Melanoma is a deadly form of skin cancer that originates from melanocytes in the skin. Skin is a major barrier to drug delivery. Transferosome is a liquid nanoformulation that has the capacity for deeper skin penetration. The transferosome was prepared from standardized Piper longum fruit ethanolic extract (PLFEE) and loaded into gel to form a transgelosome for improved skin application and patient compliance. Compared with extract-loaded plain gel, the transgelosome showed good pharmaceutical properties with better activity in melanoma (B16F10)-bearing female C57BL/6 mice. The therapeutic activity of the standard anticancer drug dacarbazine was improved with the prepared PLFEE transgelosome.


Assuntos
Melanoma , Piper , Camundongos , Animais , Camundongos Endogâmicos C57BL , Melanoma/tratamento farmacológico , Extratos Vegetais , Pele , Administração Cutânea , Etanol
16.
Polymers (Basel) ; 15(14)2023 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-37514479

RESUMO

The optimal process conditions for fabricating carbon nanotube (CNT)/polyvinylidene fluoride (PVDF) fibers with varying properties using a wet spinning process were experimentally determined. A dope solution was prepared using multi-walled nanotubes, PVDF, and dimethylacetamide, and appropriate materials were selected. Design parameters affecting the chemical and physical properties of CNT/PVDF fibers, such as bath concentration, bath temperature, drying temperature, and elongation, were determined using a response surface method. The wet-spinning conditions were analyzed based on the tensile strength and electrical conductivity of the fibers using an analysis of variance and interaction analysis. The optimized process conditions for fabricating CNT/PVDF fibers with different properties were derived and verified through fabrication using the determined design parameters.

17.
Environ Sci Pollut Res Int ; 30(34): 82387-82405, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37326738

RESUMO

This research aims to remove two phenothiazines, promazine (PRO) and promethazine (PMT), from their individual and binary mixtures using olive tree pruning biochar (BC-OTPR). The impact of individual and combinatory effects of operational variables was evaluated for the first time using central composite design (CCD). Simultaneous removal of both drugs was maximized utilizing the composite desirability function. At low concentrations, the uptake of PRO and PMT from their individual solutions was achieved with high efficiency of 98.64%, 47.20 mg/g and 95.87%, 38.16 mg/g, respectively. No major differences in the removal capacity were observed for the binary mixtures. Characterization of BC-OTPR confirmed successful adsorption and showed that the OTPR surface was predominantly mesoporous. Equilibrium investigations revealed that the Langmuir isotherm model best describes the sorption of PRO/PMT from their individual solutions with maximum adsorption capacities of 640.7 and 346.95 mg/g, respectively. The sorption of PRO/PMT conforms to the pseudo-second-order kinetic model. Regeneration of the adsorbent surface was successfully done with desorption efficiencies of 94.06% and 98.54% for PRO and PMT, respectively, for six cycles.


Assuntos
Olea , Poluentes Químicos da Água , Águas Residuárias , Prometazina , Promazina , Cinética , Adsorção , Carvão Vegetal , Poluentes Químicos da Água/análise , Concentração de Íons de Hidrogênio
18.
Heliyon ; 9(5): e16254, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37251871

RESUMO

Blood clot formation increases cases of myocardial infarction (AMI) and stroke, thus urges directing much research works for treatment and prevention of the causes. One of these directions is the microbial production of fibrinolytic enzymes as thrombolytic agents. In the current work, Bacillus subtilis Egy has been used for enzyme production under solid state fermentation. Among twelve nutrient meals in addition to wheat bran as a control fodder yeast yielded the highest enzyme activity reaching 114U/g. Applying statistical model for optimization of enzyme production revealed that 3.6%, fodder yeast; 40%, moisture content; 6 days, incubation period and 2%, inoculum size were the optimum conditions for maximum fibrinolytic enzyme production (141.02 U/g) by Bacillus subtilis Egy under solid-state fermentation The model was significant and data were experimentally validated. The produced fibrinolytic enzyme was evaluated for in vitro and in vivo cytotoxicity. In-vivo examination of the enzyme resulted in no mortality during the first 24 h after treatment. After 14 days, the results revealed no significant changes detected in hematological parameters (RBCs, MCV, hemoglobin except WBCs which showed an increase for both sexes. Histopathological examination of liver and kidney of rats received oral and subcutaneous treatments showed normal architecture. The data showed the applicability of the produced enzyme for the treatment of blood clot with no significant effect on living cells or on physiological functions.

19.
Toxics ; 11(3)2023 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-36976968

RESUMO

Neonicotinoid insecticides (NEOs) are commonly used to prevent unwanted insects in urban fields. Degradation processes have been one of the important environmental behaviors of NEOs in an aquatic environment. In this research, hydrolysis, biodegradation, and photolysis processes of four typical NEOs (i.e., thiacloprid (THA), clothianidin (CLO), acetamiprid (ACE), and imidacloprid (IMI)) were examined through the adoption of response surface methodology-central composite design (RSM-CCD) for an urban tidal stream in South China. The influences of multiple environmental parameters and concentration levels on the three degradation processes of these NEOs were then evaluated. The results indicated that the three degradation processes of the typical NEOs followed a pseudo-first-order reaction kinetics model. The primary degradation process of the NEOs were hydrolysis and photolysis processes in the urban stream. The hydrolysis degradation rate of THA was the highest (1.97 × 10-5 s-1), and that of CLO was the lowest (1.28 × 10-5 s-1). The temperature of water samples was the main environmental factor influencing the degradation processes of these NEOs in the urban tidal stream. Salinity and humic acids could inhibit the degradation processes of the NEOs. Under the influence of extreme climate events, the biodegradation processes of these typical NEOs could be suppressed, and other degradation processes could be further accelerated. In addition, extreme climate events could pose severe challenges to the migration and degradation process simulation of NEOs.

20.
Talanta ; 252: 123799, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36027621

RESUMO

According to the annual production of plastics worldwide, in 2020 about 370 million tons of plastic were produced in the world. Chemical recycling, particularly pyrolysis of plastic wastes, could be a valuable solution to resolve these problems and provide an alternative pathway to produce "recycled" chemical products for the petrochemical industry. Nevertheless, the pyrolysis oils need a detailed characterization before the upgrading test to re-use them to generate new recycled products. Multidimensional gas chromatography coupled with both low- and high-resolution time-of-flight mass spectrometers was employed for a detailed investigation among and within different chemical classes present in bio-plastic oil. The presence of several isomeric species as well as homologs series did not allow a reliable molecular identification, except for a few compounds that showed both MS similarity >800/1000 and retention index within ±20. Indeed, the identification of several isomeric species was assessed by high-resolution mass spectrometry equipped with photoionization interface. This soft ionization mode was an additional filter in the identification step allowing unambiguous identification of analytes not identified by the standard electron ionization mode at 70 eV. The injection method was also optimized using a central composite design to successfully introduce a wide range of carbon number compounds without discrimination of low/high boiling points.


Assuntos
Plásticos , Pirólise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Espectrometria de Massas/métodos , Óleos de Plantas/química , Compostos Orgânicos
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