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1.
Molecules ; 27(23)2022 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-36500331

RESUMEN

The emerging concepts of sustainable textiles and controlled production strategy demands ideally zero emissions of contaminants into the aquatic environment. However, the currently in-practiced conventional processes in textiles dispose of a number of contaminants especially super toxic synthetic dyes as effluents. In recent years, nanomaterials have become attractive choice for eco-friendly removal of organic dyestuff. Accordingly, this article reports synthesis and characterization of biocomposite wherein copolymer of polyaniline (PANI) and Polypyrrole (PPY) was grafted onto hydroxyethyl cellulose (HEC). Further, adsorption properties of as-prepared composite were evaluated using textile dyes Rhodamine B (RhB) and methyl Orange (MO)- as model adsorbate. The characterization of novel biocomposite (HEC/PANI-PPy) was carried out using Fourier Transform Infrared (FT-IR), Brunauer-Emmett-Teller analyzer (BET), Scanning Electron Microscope (SEM), and powder X-ray diffraction (XRD). The operational parameters such as dye initial concentration, adsorbent amount, pH and contact time were also studied to evaluate the efficiency level of the prepared biocomposite. Interestingly, the composite-mediated adsorption of RhB and MO followed pseudo-second order and the Langmuir isotherm. It is found that the adsorption capacity HEC/PANI-PPy is 30.06 and 29.3 for RhB and MO respectively. Thus, HEC/PANI-PPy is an inexpensive and highly efficient adsorbent that could be employed for could be employed for the separation and removal of toxic organic dyes from polluted textile effluents.


Asunto(s)
Colorantes , Contaminantes Químicos del Agua , Colorantes/química , Polímeros/química , Pirroles/química , Espectroscopía Infrarroja por Transformada de Fourier , Contaminantes Químicos del Agua/química , Adsorción , Celulosa , Cinética
2.
Molecules ; 27(22)2022 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-36431778

RESUMEN

In the present work, sulfur-doped manganese ferrites S@Mn(Fe2O4) nanoparticles were prepared by using the sol-gel and citrate method. The concentration of sulfur varied from 1 to 7% by adding Na2S. The samples were characterized by performing Fourier Transformed Infrared Spectroscopy (FTIR), Energy Dispersive X-ray (EDX), X-ray diffraction (XRD), Scanning Electron Microscopy (SEM) and Ultraviolet-Visible spectroscopy (UV-Visible). The synthesized sulfur-doped manganese ferrites were applied to evaluate the photocatalytic degradation of the dyes. Further, the degradation studies revealed that the nanoparticles successfully degraded the methylene blue dye by adding a 0.006 g dose under the sunlight. The sulfur-doped manganese ferrite nanoparticles containing 3% sulfur completely degraded the dye in 2 h and 15 min in aqueous medium. Thus, the ferrite nanoparticles were found to be promising photocatalyst materials and could be employed for the degradation of other dyes in the future.


Asunto(s)
Nanopartículas , Luz Solar , Manganeso/química , Catálisis , Nanopartículas/química , Colorantes/química , Cationes , Azufre
3.
Molecules ; 27(17)2022 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-36080245

RESUMEN

The synthesis of MMT and poly(o-anisidine) (MMT/POA) clay nanocomposites was carried out by using the chemical oxidative polymerization of POA and MMT clay with POA, respectively. By maintaining the constant concentration of POA, different percentage loads of MMT clay were used to determine the effect of MMT clay on the properties of POA. The interaction between POA and MMT clay was investigated by FTIR spectroscopy, and, to reveal the complete compactness and homogeneous distribution of MMT clay in POA, were assessed by using scanning-electron-microscope (SEM) analysis. The UV-visible spectrum was studied for the optical and absorbance properties of MMT/POA ceramic nanocomposites. Furthermore, the horizontal burning test (HBT) demonstrated that clay nanofillers inhibit POA combustion.


Asunto(s)
Retardadores de Llama , Nanocompuestos , Compuestos de Anilina , Bentonita/química , Arcilla , Nanocompuestos/química
4.
Pak J Pharm Sci ; 32(6(Supplementary)): 2829-2834, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32024621

RESUMEN

Diabetes Mellitus is a chronic disease in which the infected cells do not have the ability to produce sufficient amount of insulin that resulted in the abnormality of carbohydrates metabolism and an increase in blood glucose level. Long time exposure to Diabetes Mellitus resulted in failure or dysfunction of different organs like kidneys, nerves, heart, eyes, etc. A common practice to cure diabetes is the use of α-glucosidase inhibitors which help in lowering the blood glucose level. We presented 1,2-benzothiazine 1,1-dioxide derivatives as novel and more potent α-glucosidase inhibitors via their in vitro and in silico screenings. Excellent enzyme inhibitions were observed for compounds 2, 8, 10 and 12 having IC50 values of 6.91, 14.0, 4.2, 5.9 and 29.2µ respectively which were found better than the reference acarbose (IC50=38.31µM). Molecular docking studies suggested high binding energies and good binding interactions of these compounds with the active site residues of the receptor protein. A good agreement was found between the results of both modes of evaluation. Moreover, the envisioned candidates have a good potential to treat diabetes.


Asunto(s)
Diabetes Mellitus/tratamiento farmacológico , Inhibidores de Glicósido Hidrolasas/farmacología , Hidrazinas/farmacología , Hipoglucemiantes/farmacología , Tiazinas/farmacología , alfa-Glucosidasas/metabolismo , Acarbosa/farmacología , Humanos , Cinética , Simulación del Acoplamiento Molecular/métodos , Relación Estructura-Actividad
5.
Environ Sci Pollut Res Int ; 28(36): 49958-49966, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33948834

RESUMEN

Environmental friendly products particularly natural dyes are going to be much popular around the globe due to their non-toxic and bio-degradable nature. The current study was planned to enhance the dyeability of walnut bark having juglone as a reddish-brown natural dye under ultrasonic radiation as an environment-friendly and green tool After conducting series of experiments, it has been found that wool (RW) and extract (RE) after ultrasonic treatment for 45 min, when dyed for 45 min at 55°C using an acidic bath of 3 pH has given good color strength on the wool fabric. To develop the new shades, sustainable and eco-label chemicals (Fe, Al, and tannic acid) and four bio-mordants such as Acacia bark, Turmeric, Henna, and Pomegranate were also applied at optimum conditions. It is studied that 3% of turmeric extract as pre-bio-mordant and 5% of Acacia extract as post-bio-mordant has given excellent color characteristics as compared to their synthetic. It is concluded that ultrasonic treatment being an eco-friendly tool has a great potential to improve the dyeability of natural reddish-brown dye from walnut bark and the inclusion of sustainable biosources as a color modifier has value-added the natural dyeing process with excellent color ratings.


Asunto(s)
Colorantes , Juglans , Animales , Naftoquinonas , Corteza de la Planta , Lana , Fibra de Lana
6.
Curr Org Synth ; 17(6): 457-463, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32392115

RESUMEN

BACKGROUND: The pyrano[2,3-c]pyrazole derivatives are important building blocks of many biologically active compounds owing to their diverse biological potential for example, anti-inflammatory, anticancer, anti-microbial and anti-oxidant properties. OBJECTIVE: Keeping in mind the wide range of applications of pyrano[2,3-c]pyrazoles, herein we intended to develop a novel synthetic methodology for dihydropyranopyrazoles. We were also interested in determining the influence of amino acids and dipeptides as a catalyst on the synthesis of pyrano[2,3-c]pyrazole derivatives. METHODS: To achieve our objectives, we used a one-pot multi-component reaction of ethyl 3-oxobutanoate, propanedinitrile, hydrazine monohydrate and several substituted benzaldehydes by using different catalysts and solvents to synthesize our desired products in the presence of various catalysts. RESULTS AND DISCUSSION: We found that optimal conditions for the preparation of pyrano[2,3-c]pyrazoles were L-cysteine (0.5 mol) in the presence of water:ethanol (9:1) at 90 °C. Various 1,4-dihydropyrano[2,3- c]pyrazoles were afforded by using several substituted benzaldehydes in 66-97% yields. CONCLUSION: We described a green and environmentally benign method to synthesize pyrano[2,3-c]pyrazoles in a one-pot four component reaction of ethyl 3-oxobutanoate, propanedinitrile, hydrazine monohydrate and different substituted benzaldehyde in the presence of L-cysteine in aqueous ethanol (9:1) at 90 oC. Excellent yields of the products, simple work-up, easily available starting materials, use of green solvents, naturally occurring catalyst, non-toxicity, non-chromatographic purification and environmentally benign reaction conditions are some main advantages of this protocol.


Asunto(s)
Cisteína/química , Piranos/síntesis química , Pirazoles/síntesis química , Benzaldehídos/química , Catálisis , Tecnología Química Verde/métodos , Agua/química
7.
J Food Prot ; 83(8): 1284-1288, 2020 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-32678886

RESUMEN

ABSTRACT: A total of 133 samples of whole wheat and barley grains and wheat and barley flour collected from retail markets in the main cities of Punjab, Pakistan, were analyzed for the mycotoxin fumonisin B1 (FB1) using reverse phase high-performance liquid chromatography with fluorescence detection. Of these samples, 120 (90%) were positive for FB1, and 75 (63%) of the 120 positive samples had FB1 concentrations higher than the European Union maximum (200 µg/kg). The limit of detection was 4 µg/kg. The highest mean (±SD) concentration of FB1 was found in whole wheat samples, 980.5 ± 211.4 µg/kg. The calculated dietary intakes of FB1 from wheat and barley flours were 4,456 and 503.7 ng/g of body weight per day, respectively.


Asunto(s)
Fumonisinas , Hordeum , Contaminación de Alimentos/análisis , Fumonisinas/análisis , Pakistán , Triticum
8.
J Food Prot ; 81(5): 806-809, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29637809

RESUMEN

Two hundred ten samples of selected vegetables (okra, pumpkin, tomato, potato, eggplant, spinach, and cabbage) from Faisalabad, Pakistan, were analyzed for the analysis of heavy metals: cadmium (Cd), lead (Pb), arsenic (As), and mercury (Hg). Inductively coupled plasma optical emission spectrometry was used for the analysis of heavy metals. The mean levels of Cd, Pb, As, and Hg were 0.24, 2.23, 0.58, and 7.98 mg/kg, respectively. The samples with Cd (27%), Pb (50%), and Hg (63%) exceeded the maximum residual levels set by the European Commission. The mean levels of heavy metals found in the current study are high and may pose significant health concerns for consumers. Furthermore, considerable attention should be paid to implement comprehensive monitoring and regulations.


Asunto(s)
Contaminación de Alimentos/análisis , Metales Pesados/análisis , Verduras/química , Pakistán
9.
Chem Cent J ; 12(1): 46, 2018 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-29700704

RESUMEN

Electrically conductive polyorthochloroaniline/chromium nanocomposites (POC/Cr NCs) were prepared by in situ chemical oxidative polymerization of orthochloroaniline in the presence of Cr nanoparticles (Cr NPs). The load percentage of Cr nanofiller was varied in POC matrix to investigate the effect of Cr nanoparticles on the properties of the nanocomposites. The composition, structure, and morphology of POC and its composites were examined by Scanning electron microscopy, Fourier transform infrared spectroscopy, and UV-visible spectroscopic analysis. The antibacterial potential of POC and its composites was evaluated by the disc diffusion method against Escherichia coli and Bacillus subtilis. The results showed the improved antibacterial potential with the increase in the load percentage of nanofiller. The electrical conductivity of polymer and its composites was measured and correlated with the load percentage. The results showed that electrical conductivity of the composites was enhanced with the increase in load percentage of Cr nanoparticles.

10.
Int J Biol Macromol ; 79: 377-87, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25964178

RESUMEN

The trend of using biopolymers in combination with synthetic polymers was increasing rapidly from last two or three decades. Polysaccharide based biopolymers especially starch, cellulose, chitin, chitosan, alginate, etc. found extensive applications for different industrial uses, as they are biocompatible, biodegradable, bio-renewable resources and chiefly environment friendly. Segment block copolymer character of polyurethanes that endows them a broad range of versatility in terms of tailoring their properties was employed in conjunction with various natural polymers resulted in modified biomaterials. Alginate is biodegradable, biocompatible, bioactive, less toxic and low cost anionic polysaccharide, as a part of structural component of bacteria and brown algae (sea weed) is quite abundant in nature. It is used in combination with polyurethanes to form elastomers, nano-composites, hydrogels, etc. that especially revolutionized the food and biomedical industries. The review summarized the development in alginate based polyurethanes with their potential applications.


Asunto(s)
Alginatos/química , Materiales Biocompatibles/química , Nanocompuestos/química , Poliuretanos/química , Biodegradación Ambiental , Materiales Biomiméticos/química , Celulosa/química , Quitina/química , Quitosano/química , Ácido Glucurónico/química , Ácidos Hexurónicos/química , Humanos , Hidrogeles/química , Poliuretanos/síntesis química
11.
Int J Biol Macromol ; 62: 670-6, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24120963

RESUMEN

Hydroxy terminated polybutadiene (HTPB)-chitin based polyurethanes (PUs) with controlled hydrophobicity were synthesized using HTPB and toluene diisocyanate (TDI). The prepolymer was extended with different mass ratios of chitin and 1,4-butane diol (BDO). The effect of chitin contents in chain extender (CE) proportions on surface properties was studied and investigated. Incorporation of chitin contents into the final PU showed decrease in contact angle value of water drop, water absorption (%) and swelling behavior. The antibacterial activity of the prepared samples was affected by varying the chitin contents in the chemical composition of the final PU. The results demonstrated that the use of prepared material can be suggested as non-absorbable suture.


Asunto(s)
Butadienos/química , Quitina/química , Elastómeros/química , Poliuretanos/química , Absorción , Antiinfecciosos/química , Antiinfecciosos/farmacología , Interacciones Hidrofóbicas e Hidrofílicas , Estructura Molecular , Poliuretanos/farmacología , Propiedades de Superficie , Agua/química
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