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1.
Molecules ; 29(11)2024 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-38893494

RESUMO

Syzgium cumini (L.) Skeels powder (S. cumini powder), also known as Jamun, is well-known for its various medical and health benefits. It is especially recognized for its antidiabetic and antioxidant properties. Thus, S. cumini powder is used in various industries, such as the food and cosmetic industries. In this work, the fruit of S. cumini was utilized; its seeds were extracted, dried, and ground into powder. The ground powders were subjected to various techniques such as physicochemical tests, Fourier transform infrared (FTIR) spectroscopy, X-ray diffractometry (XRD), particle size analysis, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and antioxidant analysis. From the physicochemical tests, it was revealed that the jamun seed filler contained cellulose (43.28%), hemicellulose (19.88%), lignin (23.28%), pectin (12.58%), and wax (0.98%). The FTIR analysis supported these results. For instance, a peak at 2889 cm-1 was observed and associated with CH stretching, typically found in methyl and methylene groups, characteristic of cellulose and hemicellulose structures. The XRD results demonstrated that the crystallinity index of the jamun seed filler was 42.63%. The particle analysis indicated that the mean (average) particle size was 25.34 µm. This observation was ensured with SEM results. The EDX spectrum results showed the elemental composition of the fillers. Regarding thermal degradation, the jamun seed filler had the ability to withstand temperatures of up to 316.5 °C. Furthermore, endothermic and exothermic peaks were observed at 305 °C and 400 °C, respectively. Furthermore, the antioxidant property of the powder displayed a peak scavenging activity of 91.4%. This comprehensive study not only underscores the viability of S. cumini powder as a sustainable and effective particulate filler in polymer composites but also demonstrates its potential to enhance the mechanical properties of composites, thereby offering significant implications for the development of eco-friendly materials in various industrial applications.

2.
Environ Res ; 238(Pt 2): 117288, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-37797665

RESUMO

Hydrogen production, catalytic organic synthesis, carbon dioxide reduction, environmental purification, and other major fields have all adopted photocatalytic technologies due to their eco-friendliness, ease of use, and reliance on sunlight as the driving force. Photocatalyst is the key component of photocatalytic technology. Thus, it is of utmost importance to produce highly efficient, stable, visible-light-responsive photocatalysts. CIS stands out among other visible-light-response photocatalysts for its advantageous combination of easy synthesis, non-toxicity, high stability, and suitable band structure. In this study, we took a brief glance at the synthesis techniques for CIS after providing a quick introduction to the fundamental semiconductor features, including the crystal and band structures of CIS. Then, we discussed the ways doping, heterojunction creation, p-n heterojunction, type-II heterojunction, and Z-scheme may be used to modify CIS's performance. Subsequently, the applications of CIS towards pollutant degradation, CO2 reduction, water splitting, and other toxic pollutants remediation are reviewed in detail. Finally, several remaining problems with CIS-based photocatalysts are highlighted, along with future potential for constructing more superior photocatalysts.


Assuntos
Poluentes Ambientais , Recuperação e Remediação Ambiental , Catálise , Luz , Tecnologia
3.
Chem Biodivers ; : e202300970, 2023 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-37715949

RESUMO

BACKGROUND: Alpinia calcarata (AC) Roscoe of Zingiberaceae popularly known as lesser galangal has a widespread occurrence in China, India, Sri-Lanka, Bangladesh, Malaysia, Indonesia and Thailand. Essential oil (Eoil) was obtained from leaves/rhizomes of AC via hydro-distillation process. METHODS: To identify chemical ingredients in oil from leaves/rhizomes of AC through GC/MS technique for volatile components and their anti-oxidant, inflammatory/diabetic activities. RESULTS: The 38 and 65 components were found to make up 99.9 and 99.6 %, respectively in total of Eoil composition of AC leaves/rhizomes. Key chemical constituents were eucalyptol (28.7 % in leaves; 25.4 % in rhizomes), camphor (12.8 % in leaves; 4.2 % in rhizomes), and carotol (9.8 % in leaves; 5.6 % in rhizomes) found in oil of AC leaves/rhizomes. Colorimetric assay showed anti-oxidant activities in leaves and rhizomes are IC50 =71.01±0.71 µg/mL and IC50 =73.83±0.49 µg/mL, respectively in the Eoils. Eoils had high anti-oxidant capabilities in IC50 -values of AC-L-Eoil=43.09±0.82&AC-Rh-Eoil=68.11±0.87 in reducing power in µg/mL was found. Albumin test of rhizome oil had IC50 -values of 15.19±0.25 µg/mL. Concentrations range of 7.81 µg/mL and 250 µg/mL in the Eoils of AC leaves and rhizome, respectively by α-glucosidase inhibition assay. CONCLUSION: Our findings demonstrated that leaf oil was slightly more promising results than rhizome oil of AC extract, which was ultimately showed medicinal potential of secondary metabolites with anti-oxidant, diabetic/inflammatory activities. Further, Eoils of AC have a wide range of pharmacological potential and promising anti-diabetic effects.

4.
Macromol Rapid Commun ; 43(17): e2100862, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35609116

RESUMO

Application of natural fiber-polymer composites (NFPCs) in different industrial applications provides competitive edge due to their lightweight, higher specific mechanical properties than glass fibers, sustainability, and lower cost involved in production. There are certain challenges associated with natural fibers and their reinforcement in composites such as poor bonding between the fibers and matrix due to their contradictory nature of characteristics, moisture absorption, lower thermal properties, and poor interfacial adhesion between the natural fiber and polymer matrix. The challenges involved in NFPCs need to be overcome to produce materials with relatively equivalent properties to those of conventional composites and other metallic structures. Several researchers around the globe have conducted investigations with the primary attention being paid to the modification of natural fibers and matrix by employing surface treatments and other chemical treatment methods. In order to address the need for eco-friendly and sustainable materials in different domains, a comprehensive review on natural fibers and their sources, available matrix materials, modification techniques, mechanical and thermal properties of NFPCs, is needed for better understanding of the behavior of NFPCs. This work provides the information and holistic view of natural fiber-reinforced composites based on the results obtained from modification techniques, with the view of focusing the review in terms of different chemical and physical treatment techniques, modification of fibers and matrix, and enhanced mechanical and thermal properties in the composites.


Assuntos
Polímeros , Polímeros/química , Propriedades de Superfície
5.
J Gastroenterol Hepatol ; 37(12): 2264-2271, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36272130

RESUMO

BACKGROUND AND AIM: Diagnosis of abdominal TB is an exigent task due to variable anatomical sites and non-specific clinical manifestations that closely resemble other diseases. Most of the available diagnostic modalities yield low sensitivities and need expertise to handle the specialized equipment. Hence, there is an urgent need to develop a rapid and reliable diagnostic test, so as to reduce the unnecessary morbidity. Therefore, we designed a multi-targeted loop-mediated isothermal amplification (MT-LAMP) for diagnosing abdominal TB. METHODS: We evaluated an MT-LAMP (using mpt64 and IS6110) to diagnose abdominal TB within ascitic fluids and intestinal/peritoneal biopsies and compared these results with multiplex-PCR (M-PCR) using the same targets. MT-LAMP products were analyzed by gel electrophoresis and visual detection methods, that is, hydroxy naphthol blue and SYBR Green I reaction. RESULTS: Sensitivities of 80.9% and 84.6% were obtained in suspected (n = 42) and total abdominal TB (n = 52) cases, respectively by gel-based MT-LAMP, with 97.3% (n = 37) specificity in non-TB controls. Notably, sensitivities attained by gel-based/SYBR Green I MT-LAMP in both clinically suspected and total abdominal TB cases were significantly higher (P < 0.05) than M-PCR. Furthermore, sensitivity obtained with SYBR Green I was equivalent to that of gel-based MT-LAMP, while somewhat lesser specificity (94.6%) was attained with SYBR Green I, compared with gel-based MT-LAMP. CONCLUSION: Both gel-based and SYBR Green MT-LAMP exhibited equivalent sensitivities to diagnose abdominal TB. Because SYBR Green LAMP is easier to perform than a gel-based assay, we are currently focused on improving the specificity of this assay so as to develop a diagnostic kit.


Assuntos
Tuberculose , Humanos , Tuberculose/diagnóstico
6.
Molecules ; 26(1)2021 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-33466486

RESUMO

Cyanobacteria (blue-green microalgae) are ubiquitous, Gram-negative photoautotrophic prokaryotes. They are considered as one of the most efficient sources of bioactive secondary metabolites. More than 50% of cyanobacteria are cultivated on commercial platforms to extract bioactive compounds, which have bene shown to possess anticancer activity. The chemically diverse natural compounds or their analogues induce cytotoxicity and potentially kill a variety of cancer cells via the induction of apoptosis, or altering the activation of cell signaling, involving especially the protein kinase-C family members, cell cycle arrest, mitochondrial dysfunctions and oxidative damage. These therapeutic properties enable their use in the pharma and healthcare sectors for the betterment of future generations. This review provides a baseline overview of the anti-cancerous cyanobacterial bioactive compounds, along with recently introduced nanomaterials that could be used for the development of new anticancer drugs to build a healthy future for mankind.


Assuntos
Antineoplásicos/farmacologia , Produtos Biológicos/farmacologia , Cianobactérias/metabolismo , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos/métodos , Nanopartículas/administração & dosagem , Neoplasias/tratamento farmacológico , Cianobactérias/química , Humanos , Nanopartículas/química , Preparações Farmacêuticas , Nanomedicina Teranóstica
7.
Int J Biol Macromol ; 266(Pt 2): 131145, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38574932

RESUMO

Extracellular matrix (ECM) contains hyaluronic acid (HA) as its integral part that is involved in numerous functional activities within the body. Degradation of HA by hyaluronidase enzyme involved in many pathophysiological conditions such as asthma, arthritis, COPD and in venom spreading during envenomation. Inhibitor of hyaluronidase enzyme has a wide range of application along with the hyaluronan-hyaluronidase system. In this present study, we have evaluated the inhibitory effect of garcinol against hyaluronidase from Hippasa partita spider venom (HPHyal), bovine testicular hyaluronidase (BTH) and human serum hyaluronidase. Garcinia indica fruit rind has been used to isolate the active component garcinol. Garcinol has been used in treatment of diverse ailments. Garcinol has exhibited anti-oxidant, anti-inflammatory, HAT inhibition and miRNA deregulator in development and progression of cancers. Experimental data have shown that garcinol completely inhibited all the three tested hyaluronidase enzymes. The inhibition was found to be non-competitive pattern with reversible type. In the docking study, garcinol with hyaluronidase enzyme has been stabilized by hydrogen bonding and hydrophobic interactions. Thus, garcinol could be a potent novel inhibitor of hyaluronidase enzyme which can be further used for pharmacotherapeutic applications.


Assuntos
Inibidores Enzimáticos , Hialuronoglucosaminidase , Simulação de Acoplamento Molecular , Terpenos , Hialuronoglucosaminidase/antagonistas & inibidores , Hialuronoglucosaminidase/metabolismo , Humanos , Terpenos/farmacologia , Terpenos/química , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/química , Animais , Bovinos
8.
Int J Biol Macromol ; 273(Pt 2): 133147, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38878934

RESUMO

Wound healing involves several cellular and molecular pathways. Tridax procumbens activates genetic pathways with antibacterial, antioxidant, anticancer, and anti-inflammatory properties, aiding wound healing. This study purified Procumbenase, a serine protease from T. procumbens extract, using gel filtration (Sephadex G-75) and ion exchange (CM-Sephadex C-50) chromatography. Characterization involved analyses of protease activity, RP-HPLC, SDS-PAGE, gelatin zymogram, PAS staining, mass spectrometry, and circular dichroism. Optimal pH and temperature were determined. Protease type was identified using inhibitors. Wound-healing potential was evaluated through tensile strength, wound models, hydroxyproline estimation, and NIH 3T3 cell scratch analysis. In incision wound rat models, Procumbenase increased tensile strength on day 14 more than saline and Povidone­iodine. It increased wound contraction by 89 % after 10 days in excision wound models, attaining full contraction by day 15 and closure by day 21. Scarless wound healing was enhanced by 18 days of epithelialization against 22 and 21 days for saline and povidone­iodine. Procumbenase increased hydroxyproline concentration 2.53-fold (59.93 ± 2.89 mg/g) compared to saline (23.67 ± 1.86 mg/g). In NIH 3 T3 cell scratch assay, Procumbenase increased migration by 60.93 % (50 µg) and 60.57 % (150 µg) after 48 h. Thus, Procumbenase is the primary bioactive molecule in T. procumbens, demonstrates scar-free wound healing properties.


Assuntos
Extratos Vegetais , Serina Proteases , Cicatrização , Cicatrização/efeitos dos fármacos , Animais , Camundongos , Ratos , Células NIH 3T3 , Serina Proteases/metabolismo , Serina Proteases/química , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Masculino , Cicatriz/tratamento farmacológico , Hidroxiprolina/metabolismo , Resistência à Tração
9.
Chemosphere ; 316: 137839, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36640984

RESUMO

In this study graphitic carbon nitride (g-C3N4 or GCN) and phosphorus doped graphitic carbon nitride (p-g-C3N4 or PCN) were prepared using facile thermal polycondensation method. Phosphorus doping was employed to preserve the non-metallic nature of GCN. The AgCl/PCN/Fe3O4 heterojunction was synthesized using a simple in-situ route. The photocatalytic performance of the GCN, PCN, Fe3O4 and AgCl/PCN/Fe3O4 was tested towards 2, 4-dimethylphenol (DMP) pollutant. The work explored improvement in physiochemical properties and reduction of band gap of GCN after P doping (through Tauc's plot method). Coupling with AgCl (silver halide) also enhanced photoinduced charge carriers' separation and migration ability due to apt band alignment among both AgCl and PCN photocatalysts which resulted in formation of direct Z-scheme charge transfer mechanism. Similarly, the incorporation of ferrimagnetic material i.e. Fe3O4 enhanced the generation of hydroxyl (•OH) radicals via photo-Fenton process and facilitated photocatalysts easy separation from the aqueous medium. Through PL and EIS analysis the enhanced charge separation and migration ability in AgCl/PCN/Fe3O4 nanocomposite was validated. The attained DMP degradation efficiency of photo-Fenton assisted AgCl/PCN/Fe3O4/H2O2 Z-scheme nanocomposite was much higher i.e. 99% compared to other photocatalysts within 60 min of visible light irradiation following pseudo-first-order kinetics. Electron paramagnetic resonance (EPR) and scavenging tests confirmed the substantial role of •OH and •O2- radicals in the photo-Fenton reaction. Furthermore, liquid chromatography-mass spectrometry (LC-MS) analysis detected the generated oxidative products and mineralization pathways associated with DMP degradation. The proposed direct Z-scheme charge transfer route presented efficient charge separation and migration ability in AgCl/PCN/Fe3O4 nanocomposite. Recycle ability of the fabricated AgCl/PCN/Fe3O4 photocatalyst was tested up to 5 cycles with 90% removal efficacy, confirming the excellent reusability and stability of AgCl/PCN/Fe3O4 photocatalyst.


Assuntos
Grafite , Peróxido de Hidrogênio , Grafite/química , Compostos de Nitrogênio/química , Água
10.
Polymers (Basel) ; 15(3)2023 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-36771900

RESUMO

Global climate change is already affecting the environment, as glaciers are receding, ice on rivers and lakes is melting, plant and animal range`s have altering, and trees are blooming early. Therefore, focus has shifted towards sustainable materials. There is a growing desire for materials that have a unique combination of qualities that metals, polymers, and other materials cannot provide, therefore scientists are turning their focus to green composites. Green composites offer a wide range of uses in automotive, aerospace, and marine applications. Composites are multiphase resources with separate interfaces that contain chemically different materials. Composites are made up of a variety of materials that are distinct in nature, and they give a set of desirable features that are superior to those of their predecessors or parents. Natural fibers are less expensive, more readily available, rust-resistant, plentiful, nontoxic, and safe for human skin, eyes, and respiratory systems. Green composites are created by combining renewable fibers with polymers (matrix) to create a new class of composites known as "green composites." This review includes studies on various animal-based fibers and their applications. In this article, recent advancements in the field of these fibers and their composites of fibers are also discussed. The physical, chemical, and mechanical properties are also discussed in this paper. Moreover, the benefits and drawbacks of using these fibers are also discussed in detail. Finally, the paper gives an outline of the topic. The results from composites constructed from each fiber are provided, along with appropriate references for more in-depth analysis studies. This review is specially performed to strengthen the knowledge bank of the young researchers working in the field of natural composites.

11.
Int J Biol Macromol ; 250: 125803, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37451385

RESUMO

Pectin, a biological macromolecule-doped zirconium (IV) Phosphate is reported as a novel ion exchanger which has been characterized by few physico-chemical characterization techniques such as FTIR analysis, XRD, TGA/DTA, DSC, SEM study, UV-vis spectrophotometry and elemental analysis. The method of synthesis along with ion exchange characterization has also been reported including ion exchange capacity, thermal stability, concentration and elution study. Adsorption study has been explored for few alkaline earths and transition metal ions in several acidic media. Based on adsorption study, it has been found that the reported ion exchanger has shown enantioselectivity for mercury (II) ions. Hence, few binary separations have been performed on lab-made samples depicting that the material would be of great importance in water pollution control. In addition to it, antimicrobial activity of the material on some microorganisms has been studied revealing the highest antimicrobial activity towards Ecoli ESS 2231 which would be added application in terms of water purification. Moreover, the exchanger is found stable up to 200 °C by retaining 90.6 % of its capacity whereas up to 400 °C, it exhibits decrement by retaining 75.5 % of its ion exchange capability which provides a way to explore applications of the exchanger at a higher range of temperatures.

12.
Environ Sci Pollut Res Int ; 30(27): 71322-71339, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37160857

RESUMO

Nitrite has been linked to a variety of health issues, as well as cancer and oxygen deficiency when its allowable limit is exceeded. Nitrite monitoring and detection are required due to the negative effects on public health. Metal-organic frameworks (MOFs)-based nanomaterials/composites have recently been shown to have the potential for various biological and medical applications like sensing, imaging, and drug delivery. As a result, this research creates an efficient electrochemical sensor by incorporating MOFs into polyaniline (PANI)/carbon nanotube (CNT) cast on the GCE. In situ oxidative polymerization was used to construct an aluminum succinate MOF (Al-Succin)-incorporated CNT/PANI nanocomposite (PANI/CNT@Al-Succin) and well characterized by various characterization techniques, namely, field emission scanning electron microscopy (FE-SEM), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction spectroscopy (XRD), X-ray photoelectron spectroscopy (XPS), thermogravimetric-differential thermal analysis (TGA-DTA), cyclic voltammetry (CV), and four probes to measure DC electrical conductivity. Cyclic voltammetry and linear sweep voltammetry techniques were employed to detect nitrite on the surface of PANI/CNT@Al-Succin-modified glassy carbon electrode (GCE). PANI/CNT@Al-Succin-modified GCE demonstrated good current response and electrocatalytic property towards nitrite compared to bare GCE. The newly synthesized electrode exhibited a high electrocatalytic activity towards nitrite oxidation and showed a linear response ranging from 5.7 to 74.1 µM for CV and 8.55-92.62 µM for LSV. The obtained LOD values for CV (1.16 µM) and LSV (0.08 µM) were significantly below the WHO-defined acceptable nitrite limit in drinking water. Results of recovery studies for real samples of apple juice, orange juice, and bottled water were 98.92%, 99.38%, and 99.90%, respectively. These values show practical usability of PANI/CNT@Al-Succin in real samples.


Assuntos
Água Potável , Estruturas Metalorgânicas , Nanocompostos , Nanotubos de Carbono , Nanotubos de Carbono/química , Nitritos/análise , Alumínio/análise , Ácido Succínico , Espectroscopia de Infravermelho com Transformada de Fourier , Técnicas Eletroquímicas/métodos , Nanocompostos/química , Água Potável/análise , Succinatos/análise
13.
Polymers (Basel) ; 15(6)2023 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-36987288

RESUMO

Currently, polymer organic solar cells (POSCs) are widely utilized due to their significant application, such as low-cost power conversion efficiencies (PCEs). Therefore, we designed a series of photovoltaic materials (D1, D2, D3, D5 and D7) by the incorporation of selenophene units (n = 1-7) as π1-spacers by considering the importance of POSCs. Density functional theory (DFT) calculations were accomplished at MPW1PW91/6-311G (d, p) functional to explore the impact of additional selenophene units on the photovoltaic behavior of the above-mentioned compounds. A comparative analysis was conducted for designed compounds and reference compounds (D1). Reduction in energy gaps (∆E = 2.399 - 2.064 eV) with broader absorption wavelength (λmax = 655.480 - 728.376 nm) in chloroform along with larger charge transference rate was studied with the addition of selenophene units as compared to D1. A significantly higher exciton dissociation rate was studied as lower values of binding energy (Eb = 0.508 - 0.362 eV) were noted in derivatives than in the reference (Eb = 0.526 eV). Moreover, transition density matrix (TDM) and density of state (DOS) data also supported the efficient charge transition origination from HOMOs to LUMOs. Open circuit voltage (Voc) was also calculated for all the aforesaid compounds to check the efficiency, and significant results were seen (1.633-1.549 V). All the analyses supported our compounds as efficient POSCs materials with significant efficacy. These compounds might encourage the experimental researchers to synthesize them due to proficient photovoltaic materials.

14.
Polymers (Basel) ; 15(4)2023 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-36850293

RESUMO

The potential of nanocomposite membranes (NCMs) prepared by the sodium alginate polymer and embedded with synthesized zeolitic imidazole framework-8 (ZIF-8) as fillers having microporous structure in the application of separation of gaseous mixture generated by the process of methane reforming was assessed. ZIF-8 crystals were created through hydrothermal synthesis, with sizes varying from 50 to 70 nm. NCMs were prepared with a 15% filler loading, i.e., synthesized ZIF-8. NCMs (ZIF-8) having H2 permeability of 28 Barrer and H2/CH4 selectivity of 125 outperformed neat polymer membranes in terms of separation performance at ambient temperature and 4 kg/cm2 pressure. The purity of H2 increased to as high as 95% among the measured values. The NCMs did not, however, outperform a neat polymer membrane in terms of their ability to separate mixtures of gases. Moreover, the combination of ZIF-8 as a filler with sodium alginate was new and had not been reported previously. As a result, it is worthwhile to investigate.

15.
J Polym Environ ; 31(6): 2519-2533, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36590138

RESUMO

The poly(vinyl alcohol) (PVA) and starch-based polymeric films with a ratio of 2:8 were prepared using solution casting followed by a solvent evaporation method. Four types of membranes with varied concentrations of grapefruit seed extract (GSE) i.e., 2.5-10 wt% was incorporated in the films. The prepared membranes were assessed for transparency test, mechanical properties, surface morphology, permeability test for O2, and antimicrobial properties. The PVA/starch-10% GSE loaded film showed excellent mechanical properties showing highest 1344 ± 0.7% elongation at break but poor optical transparency with 53.8% to 68.61%. The Scanning Electron Microscopic study reveals the good compatibility between the PVA, Starch, and GSE. The gas permeability test reveals that the prepared films have shown good resistance to the O2 permeability 0.0326-0.316 Barrer at 20 kg/cm2 feed pressure for the prepared membranes showing excellent performance. By adding the little amount of GSE into the PVA/starch blend membranes showed promising antimicrobial efficacy against MNV-1. For 4 h. incubation, PVA/starch blend membranes containing 2.5%, 5%, and 10% GSE caused MNV-1 reductions of 0.92, 1.89, and 2.27 log PFU/ml, respectively. Similarly, after 24 h, the 5% and 10% GSE membranes reduced MNV-1 titers by 1.90 and 3.26 log PFU/ml, respectively. Antimicrobial tests have shown excellent performance to resist microorganisms. The water uptake capacity of the membrane is found 72% for the PVA/starch pristine membrane and is reduced to 32% for the 10% GSE embedded membrane. Since the current pandemic situation due to COVID-19 occurred by SARSCOV2, the prepared GSE incorporated polymeric blend films are the rays of hope in the packaging of food stuff.

16.
Heliyon ; 9(3): e14428, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36967975

RESUMO

Fiber-reinforced polymer (FRP) composites play a vital role in the production of structural and semi-structural components for engineering applications. The drilling process is a commonly employed machining process for FRP composites to join the FRP structural elements. Usually, the FRP composites possess a heterogeneous nature because of their multi-layered structure, hybridization, and the presence of multi-phase materials. Hence, common problems like delaminations, fuzzing, buckling, cracking, matrix and fiber burning occur during the drilling operations. These problems cause dimensional inaccuracy, poor surface finish, and tool wear and reduce the mechanical strength of the composites. The optimum drilling parameters (drill geometry, speed, feed, and depth of cut) selection for the specific materials is good to achieve effective drilling performance and better surface quality of the holes. Yet, little study has been done on how all of these factors affect the size of the drilled hole. The majority of drilling studies on FRPCs in the past have focused on how to improve the hole quality by maximizing processing conditions, and there has been little discussion on the correlation between drilling conditions, physical properties, and production techniques. This is what motivated to review the characteristics and properties analysis of FRP composites. As a consequence of this research, it is anticipated that scientists and researchers would place a greater emphasis on the drilling characteristic of the workpieces made from FRPCs than on other attributes. This review clearly presents an overview of FRP composites drilling that had progressed from 2000 to 2021. The analysis of different drilling conditions and parameters like thrust force, drill geometry, temperature, speed, and feed also includes the post-drilling analysis through delaminations, thermal damage, and surface roughness. Furthermore, the recent developments in carbon, glass, and natural fiber reinforced polymer composites are studied with both conventional and nonconventional drilling techniques. Based on the above studies, some future challenges and conclusions are drawn from this review.

17.
Gels ; 8(4)2022 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-35448135

RESUMO

Surfactants are ubiquitous materials that are used in diverse formulations of various products. For instance, they improve the formulation of gel by improving its wetting and rheological properties. Here, we describe the effects of anionic surfactants on an anesthetic drug, tetracaine hydrochloride (TCH), in NaCl solution with tensiometry and UV-visible techniques. Various micellar, interfacial, and thermodynamic parameters were estimated. The outputs were examined by using different theoretical models to attain a profound knowledge of drug-surfactant mixtures. The presence of attractive interactions among drug and surfactant monomers (synergism) in mixed micelle was inferred. However, it was found that sodium dodecyl sulfate (SDS) showed greater interactions with the drug in comparison to sodium lauryl sarcosine (SLS). The binding of the drug with surfactants was monitored with a spectroscopic technique (UV-visible spectra). The results of this study could help optimize the compositions of these mixed aggregates and find the synergism between monomers of different used amphiphiles.

18.
Biotechniques ; 73(1): 47-57, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35787144

RESUMO

A multitargeted loop-mediated isothermal amplification (MT-LAMP) assay targeting mpt64 (Rv1980c) and IS6110 was designed to diagnose genitourinary tuberculosis (GUTB) cases. While assessing gel-based, hydroxynaphthol blue (HNB) and SYBR Green I MT-LAMP assays on GUTB specimens (n = 28) in a pilot study, both gel-based/SYBR Green I assays exhibited better sensitivity than HNB LAMP. Since SYBR Green MT-LAMP is easier to perform compared with a gel-based assay, a higher number of GUTB specimens (n = 55) were evaluated by SYBR Green MT-LAMP, wherein 85.5% sensitivity and 94.4% specificity (n = 36) were obtained. Moreover, the sensitivity attained by MT-LAMP was significantly higher (p < 0.05) than with multiplex-PCR (mpt64 + IS6110). After further validating these MT-LAMP data in different epidemiological settings, this assay may be developed as a diagnostic kit.


Assuntos
Técnicas de Amplificação de Ácido Nucleico , Tuberculose , Benzotiazóis , Diaminas , Humanos , Técnicas de Diagnóstico Molecular , Projetos Piloto , Quinolinas , Sensibilidade e Especificidade
19.
Gels ; 8(2)2022 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-35200509

RESUMO

In this approach, tensiometry and UV-visible techniques are used to determine the effect of cationic gemini and conventional surfactants on tetracaine hydrochloride (TCH), an anesthetic drug. We have estimated micellar, interfacial, and energetic constraints. To gain a deep understanding of their mixed association behavior, the outputs were examined using different theoretical models. The critical micelle concentration for single and mixed amphiphiles was estimated. The cmc values of mixed amphiphiles were found between the individual amphiphiles due to strong attractive interaction (synergism) between the components after mixing. The non-ideal behavior of mixtures was confirmed by the larger values of ideal cmc than the experimental cmc values. The negative values of interaction parameter (ß) and values of activity coefficients less than unity indicate strong synergistic interaction between drug and surfactant. The stability of the mixed systems is demonstrated by the negative Gibbs free energy of micellization and excess free energy of micellization. In contrast to a single chain surfactant, a double chain surfactant (gemini) exhibits better interactions with the drug. Spectral measurements (UV-visible spectra) were used to monitor the binding of the drug with surfactant (conventional as well as gemini). Studying these mixed aggregates could help to optimize their compositions and find synergistic properties between TCH monomers and surfactants.

20.
Polymers (Basel) ; 14(2)2022 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-35054755

RESUMO

Poly(vinyl alcohol) (PVA) is an excellent membrane-forming polymer and can be modified with potato starch and methyl acrylate monomers to obtain copolymers with improved physical and chemical properties. The study presents the synthesis of poly(vinyl alcohol)-g-starch-poly(methyl acrylate) PVA-g-St-g-PMA copolymers using microwave irradiation technique and potassium persulfate initiator. Solution casting and solvent evaporation methods were adopted for the fabrication of polyvinyl alcohol-g-starch-acrylamide composite membranes. The synthesized graft copolymer was characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, and thermal analysis. The modified nanocomposite membranes were showed very promising results with the parameters permeability and selectivity. The nanocomposite membranes exhibited the advantages of easy handling and reuse.

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