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1.
J Assoc Physicians India ; 72(6): 20-22, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38881129

ABSTRACT

INTRODUCTION: Metabolic syndrome (MetS) is one of the most important emerging pandemics of the 21st century and is associated with renal dysfunction in a significant number of subjects, the association of which is shown to be of greater significance in the South Asian population. AIMS AND OBJECTIVES: The prevalence of renal dysfunction in patients with MetS is the primary outcome. The secondary outcome is to assess the strength and significance of the association between the individual components of MetS and the presence of renal dysfunction. MATERIALS AND METHODS: This is a hospital-based cross-sectional observational study conducted for 2 years in a tertiary care hospital in India. A total of 100 diagnosed subjects of MetS were taken as cases and underwent relevant blood tests. Data were collected and analyzed in a Statistical Package for the Social Sciences (SPSS) v29 sheet. RESULTS: Over a period of 18 months, 100 subjects with MetS were documented, among which 66% had albuminuria, with microalbuminuria being 24% and the rest being macroalbuminuria. Among the same subjects, 30% had an estimated glomerular filtration rate (eGFR) <60 mL/minute/1.73m2. Waist circumference (WC) [measured by the National Institutes of Health (NIH) protocol] had the strongest association with increased albuminuria (r = 0.540; p-value < 0.001) as well as reduced eGFR (r = 0.460; p-value < 0.001). CONCLUSION: All the components of MetS, for example, increased WC, hypertension, increased fasting glucose, raised triglyceride (TG), and low high-density lipoprotein (HDL), have statistically significant correlations with increased urine albumin-to-creatinine ratio (ACR) and decreased eGFR, signifying glomerular injury and renal dysfunction, respectively.


Subject(s)
Glomerular Filtration Rate , Metabolic Syndrome , Humans , Metabolic Syndrome/epidemiology , Metabolic Syndrome/physiopathology , Metabolic Syndrome/diagnosis , Cross-Sectional Studies , Female , Prevalence , Male , Middle Aged , India/epidemiology , Adult , Albuminuria/epidemiology , Waist Circumference
2.
Biomacromolecules ; 24(3): 1111-1120, 2023 03 13.
Article in English | MEDLINE | ID: mdl-36787188

ABSTRACT

Biopolymers are an attractive environmentally friendly alternative to common synthetic polymers, whereas primarily proteins and polysaccharides are the biomacromolecules that are used for making the biopolymer. Due to the breadth of side chains of such biomacromolecules capable of participating in hydrogen bonding, proteins and polysaccharide biopolymers were also used for the making of proton-conductive biopolymers. Here, we introduce a new platform for combining the merits of both proteins and polysaccharides while using a glycosylated protein for making the biopolymer. We use mucin as our starting point, whereas being a waste of the food industry, it is a highly available and low-cost glycoprotein. We show how we can use different chemical strategies to target either the glycan part or specific amino acids for both crosslinking between the different glycoproteins, thus making a free-standing biopolymer, as well as for introducing superior proton conductivity properties to the formed biopolymer. The resultant proton-conductive soft biopolymer is an appealing candidate for any soft bioelectronic application.


Subject(s)
Polysaccharides , Protons , Biopolymers/chemistry , Polysaccharides/chemistry , Polymers , Proteins , Mucins
3.
Environ Sci Technol ; 55(15): 10491-10501, 2021 08 03.
Article in English | MEDLINE | ID: mdl-34291927

ABSTRACT

Microplastic (MP) pollution-an emerging environmental challenge of the 21st century-refers to accumulation of environmentally weathered polymer-based particles with potential environmental and health risks. Because of technical and practical challenges when using environmental MPs for risk assessment, most available data are generated using plastic models of limited environmental relevancy (i.e., with physicochemical characteristics inherently different from those of environmental MPs). In this study, we assess the effect of dominant weathering conditions-including thermal, photo-, and mechanical degradation-on surface and bulk characteristics of polystyrene (PS)-based single-use products. Further, we augment the environmental relevance of model-enabled risk assessment through the design of engineered MPs. A set of optimized laboratory-based weathering conditions demonstrated a synergetic effect on the PS-based plastic, which was fragmented into millions of 1-3 µm MP particles in under 16 h. The physicochemical properties of these engineered MPs were compared to those of their environmental counterpart and PS microbeads often used as MP models. The engineered MPs exhibit high environmental relevance with rough and oxidized surfaces and a heterogeneous fragmented morphology. Our results suggest that this top-down synthesis protocol combining major weathering mechanisms can fabricate improved, realistic, and reproducible PS-based plastic models with high levels of control over the particles' properties. Through increased environmental relevancy, our plastic model bolsters the field of risk assessment, enabling more reliable estimations of risk associated with an emerging pollutant of global concern.


Subject(s)
Microplastics , Water Pollutants, Chemical , Environmental Monitoring , Environmental Pollution , Plastics , Polystyrenes , Water Pollutants, Chemical/analysis
4.
Sci Total Environ ; 788: 147670, 2021 Sep 20.
Article in English | MEDLINE | ID: mdl-34029818

ABSTRACT

The rise of microplastic (MP) pollution in the environment has been bolstering concerns regarding MPs' unknown environmental fate, transport, and potential toxicity toward living forms. However, the use of real environmental plastics for risk assessment is often hindered due to technical and practical challenges such as plastics' heterogeneity and their wide size distribution in the environment. To overcome this issue, most available data in the field is generated using plastic models as surrogates for environmental samples. In this critical review, we describe the gaps in risk assessments drawn from these plastic models. Specifically, we compare physicochemical properties of real environmental plastic particles to synthesized polymeric micro-beads, one of the most commonly used plastic models in current literature. Several surface and bulk characteristics including size, surface chemistry, polymer type, and morphology are shown to not only be inherently different between environmental MP's and synthesized micro-beads, but also drive behavior in fate, transport, and toxicity assays. We highlight the importance of expressing real-world physicochemical characteristics in representative MP models and outline how current state-of-the-art models are limited in this regard. To address this issue, we suggest future areas of research such as combinations of mechanical, photochemical, and thermal degradation processes to simulate real-world weathering, all in an effort to increase realism of plastic modeling and allow more robust and reliable environmental MP risk assessment in the future.

5.
Waste Manag ; 113: 225-235, 2020 Jul 15.
Article in English | MEDLINE | ID: mdl-32535374

ABSTRACT

In this study, banana peel (BP) and its derivatives after sequential extraction of biochemical components were evaluated for selective recovery of gold. In-depth instrumental characterizations including XPS, FTIR, XRD and HR-TEM were performed to understand the adsorption mechanisms. The biomass after lipid extraction, BP-L, demonstrated very good affinity and selectivity towards gold. In multi-metal systems containing 100 mg/L of Pt(IV), Au(III), Pd(II), Zn(II), Co(II), Ni(II) and Li(I), the selectivity coefficient increased from 978.45 in BP to 2034.70 in BP-L. Moreover, the equilibrium gold uptake was improved and reached 475.48 ± 3.08 mg/g owing to reduction-coupled adsorption mechanisms. The BP-L also showed improved gold nanoparticle formation properties that were pH-dependent. In a strategic adsorption-combined incineration process, metallic gold reaching 99.96% in purity was obtained. The BP and its derivative, BP-L have thus shown potentials for multiple applications in the areas of precious metal recovery and nanoscience.


Subject(s)
Metal Nanoparticles , Musa , Adsorption , Gold , Incineration
6.
Environ Sci Pollut Res Int ; 27(20): 24760-24771, 2020 Jul.
Article in English | MEDLINE | ID: mdl-31925694

ABSTRACT

This study aimed to select a high-performance cation-exchange resin (CER) and estimate its uptake of positively ionized tricyclic antidepressants (TCAs), i.e., amitriptyline (AMI), imipramine (IMI), clomipramine (CLO), and desipramine (DES), which are frequently used, and detected in wastewater treatment systems. For the selection of the resin, the one-point check test of AMI in distilled water was examined using several CERs. As a result, the strong-acid polystyrene CER, Dowex 50WX4-200, was selected on the basis of its outstanding uptake of AMI. The maximum adsorption capacities of Dowex 50WX4-200 for removal of the TCAs ranged from 2.53 ± 0.20 mmol/g to 3.76 ± 0.12 mmol/g, which are significantly higher when compared with those of previously reported adsorbents. This is likely because the combination of electrostatic and π-π interactions between the TCAs and Dowex 50WX4-200 may lead to high uptakes of the TCAs. Additionally, the removal efficiency of DES as a representative of the TCAs was tested in actual wastewater system containing activated sludge and miscellaneous cations. Consequently, the removal efficiencies of the DES in distilled water, aerobic wastewater, and filtered wastewater were 95.68%, 77.99%, and 56.66%, respectively. It is interesting to note that the activated sludge could also contribute to adsorption of the DES, leading to increased removability, while the cations present in the wastewater acted as competing ions, decreasing the removal efficiency.


Subject(s)
Amitriptyline , Antidepressive Agents, Tricyclic , Adsorption , Cations , Imipramine
7.
Environ Sci Pollut Res Int ; 27(1): 1053-1068, 2020 Jan.
Article in English | MEDLINE | ID: mdl-31814075

ABSTRACT

Dyes are colored compounds which are visible even at trace concentrations. Due to their recalcitrance and esthetic persistence, certain methods are unable to effectively eliminate them. So far, adsorptive treatment using activated carbons (ACs) is one of the most successful methods. In this study, we have employed orange peel (OP) as a cost-effective alternative to the expensive coal- and coir-based precursors to synthesize ACs for cationic methylene blue (MB) and anionic methyl orange (MO) dye adsorption. The pre-carbonized OP was activated via H2SO4, NaOH, KOH, ZnCl2, and H3PO4 to study the effects of activation reagents on dye removal efficiencies and mechanisms. Among several isotherm models employed to fit the adsorption data, the Langmuir and Sips models sufficiently estimated the maximum equilibrium uptakes close to the experimental values of 1012.10 ± 29.13, 339.82 ± 6.98, and 382.15 ± 8.62 mg/g, for ZnCl2-AC (MO), ZnCl2-AC (MB), and KOH-AC (MB), respectively. The adsorption mechanisms were suggested to involve electrostatic binding, pi-pi interactions, hydrogen bonding, and electron donor-acceptor reactions. Consequently, more than 99% removal efficiency was achieved from a laboratory organic wastewater sample bearing ~ 35 mg/L of MB. The results thus suggest that the synthesized ACs from agricultural waste have the tendencies to be applied to real dye wastewater treatment.


Subject(s)
Charcoal/chemistry , Coloring Agents/chemistry , Methylene Blue/chemistry , Adsorption , Agriculture , Azo Compounds , Citrus sinensis , Kinetics , Wastewater , Water Pollutants, Chemical/chemistry
8.
Waste Manag ; 89: 141-153, 2019 Apr 15.
Article in English | MEDLINE | ID: mdl-31079727

ABSTRACT

After consumption of the inner fleshy fruit, the banana peel like many other fruit peels is usually disposed of unprocessed. For sustainable development, agro-wastes including banana peels need to be converted into valuable products that will be beneficial to human and the environment. In this study, biochemical components including lipids, proteins and structural polysaccharides were sequentially extracted from banana peel, and the residuals were characterized by FE-SEM/EDX, FTIR, XRD, TGA/DSC, XPS and elemental analysis. Owing to rapid industrialization, toxic species such as metals and dyes are consistently released into the aquatic environments. Therefore, the residual biomass samples were evaluated for environmental remediation application. The adsorption performances were outstanding, with uptakes reaching 1034, 279 and 152 mg/g, for methylene blue, lead and platinum, respectively. This study thus suggests that sequential extraction and detailed characterization are useful for identification of key contributing components for development of high-performance agro-waste-based adsorbents for water treatment.


Subject(s)
Environmental Restoration and Remediation , Musa , Water Purification , Adsorption , Biomass
9.
Small ; 15(10): e1805242, 2019 Mar.
Article in English | MEDLINE | ID: mdl-30690878

ABSTRACT

Precious metals such as palladium (Pd) and platinum (Pt) are marvelous materials in the fields of electronic and catalysis, but they are tapering day by day. Zr(IV)-based metal-organic frameworks (MOFs) are competent for their recovery, notably in harsh environments, while the general powder form limits their practical application. Porous MOF-based membranes with ultraefficient metal ion permeation, strong stability, and high selectivity are, therefore, strikingly preferred. Herein, a set of polymeric fibrous membranes incorporated with the UiO-66 series are fabricated; their adsorption/desorption capabilities toward Pd(II) and Pt(IV) are evaluated from strongly acidic solutions; and the MOF-polymer compatibilities are investigated. Polyurethane (PU)/UiO-66-NH2 showed strong acid resistance and high chemical stability, which are attributable to strong π-π interactions between PU and MOF nanoparticles with a high configuration of energy. The as-fabricated MOF membranes show extremely good adsorption/desorption performances without ruptures/coalitions of nanofibers or leak of MOF nanoparticles, and successfully display the efficacy in a gravity-driven or even continuous-flow system with good recycle performance and selectivity. The as-fabricated MOF membranes set an example of potential MOF-polymer compatibility for practical applications.

11.
Chem Commun (Camb) ; 51(89): 16057-60, 2015 Nov 18.
Article in English | MEDLINE | ID: mdl-26390341

ABSTRACT

A fully exfoliated titanate layer-natural polymer amylopectin based nanocomposite, with pH responsive superior selective adsorption, separation of both cationic (MB: 599 mg g(-1) at pH 9) and anionic (MO: 558 mg g(-1) at pH 3) dyes and photodegradation properties, has been realized through simultaneous in situ layered titanate formation, exfoliation and polymerization.


Subject(s)
Coloring Agents/chemistry , Nanocomposites/chemistry , Photochemistry , Polymers/chemical synthesis , Titanium/chemistry , Adsorption , Anions/chemistry , Catalysis , Cations/chemistry , Hydrogen-Ion Concentration , Polymers/chemistry , X-Ray Diffraction
12.
Bioresour Technol ; 191: 291-9, 2015 Sep.
Article in English | MEDLINE | ID: mdl-26002148

ABSTRACT

The present study highlights the potentiality of sol-gel synthesized guar gum-graft-poly (acrylamide)/silica (g-GG/SiO2) hybrid nanocomposite toward the rapid removal of toxic reactive blue 4 (RB) and Congo red (CR) dyes from aqueous solution. Various physicochemical characterizations support the feasibility of the functionalized guar gum matrix as efficient template for the formation of homogeneous nanoscale silica particles. The composite demonstrates rapid and superior adsorption efficiency of RB (Qmax: 579.01 mg g(-1) within 40 min) and CR (Qmax: 233.24 mg g(-1) within 30 min) dyes from aqueous environment. Here, the pH driven adsorption process depends strongly on the ionic strength of the salt solution. The adsorption kinetics data predicts that pseudo second-order (surface adsorption) and intraparticle diffusion take place simultaneously. The adsorption equilibrium is in good agreement with the Langmuir isotherm, while the thermodynamics study confirms spontaneous nature of the adsorption process. Desorption study predicts the excellent regenerative efficacy of nanocomposite.


Subject(s)
Coloring Agents/isolation & purification , Galactans/chemistry , Mannans/chemistry , Nanocomposites , Plant Gums/chemistry , Silicon Dioxide/chemistry , Adsorption , Coloring Agents/toxicity , Kinetics
13.
Int J Biol Macromol ; 72: 356-63, 2015 Jan.
Article in English | MEDLINE | ID: mdl-25159884

ABSTRACT

Herein, we report the application of an efficient polymeric flocculant based on amylopectin grafted with poly (acrylic acid) (g-AP) for the treatment of synthetic effluent as well as various industrial wastewaters. The flocculation characteristics of g-AP have been explored in different pH conditions using silica suspension by measurement of residual turbidity as well as floc size. Results suggest that in acidic pH, patching mechanism is predominating while at neutral and alkaline pH, bridging is the main mechanism. In addition, aggregation of particles and particle collision models confirm that bridging mechanism is the key mechanism at alkaline condition. Further, g-AP demonstrates excellent potential as flocculant for the treatment of paper effluent, textile wastewater and shows better flocculation performance than that of commercially available flocculant. Besides, the pilot scale study of mine processwater suggests excellent efficacy of g-AP as flocculant.


Subject(s)
Amylopectin/chemistry , Waste Disposal, Fluid , Wastewater/chemistry , Water Purification , Acrylic Resins/chemistry , Flocculation , Hydrogen-Ion Concentration , Pilot Projects , Polymers/chemistry
14.
Bioresour Technol ; 170: 578-582, 2014 Oct.
Article in English | MEDLINE | ID: mdl-25164955

ABSTRACT

This work studied the application of a novel biodegradable nanocomposite based on partially hydrolyzed polyacrylamide grafted xanthan gum and nanosilica (h-XG/SiO2) towards efficient and rapid removal of toxic Pb(2+) ions from aqueous environment. The uptake ability of Pb(2+) using h-XG/SiO2 has been studied in batch adsorption experiments with variation of adsorption parameters. The excellent removal rate (99.54% adsorption within 25min) and superior adsorption capacity (Qmax=1012.15mgg(-1)) of the composite material have been explained on the basis of synergistic and chelating effects of h-XG/SiO2 with Pb(2+) ion through electrostatic interactions. The kinetics, isotherm and thermodynamics studies reveal that Pb(2+) adsorb rapidly on nanocomposite surface, which is in agreement with pseudo-second-order kinetics and Langmuir adsorption isotherm models. In consequence of excellent adsorption as well as regeneration characteristics of nanocomposite, it has been found to be a promising adsorbent towards removal of Pb(2+) ions from battery industry wastewater.


Subject(s)
Biodegradable Plastics/chemistry , Lead/chemistry , Nanocomposites/chemistry , Water Pollutants, Chemical/chemistry , Water Purification/methods , Adsorption , Hydrogen-Ion Concentration , Kinetics , Lead/toxicity , Models, Chemical , Polysaccharides, Bacterial , Silicon Dioxide , Thermodynamics , Water Pollutants, Chemical/toxicity
15.
Carbohydr Polym ; 111: 108-15, 2014 Oct 13.
Article in English | MEDLINE | ID: mdl-25037335

ABSTRACT

This article reports on the application of a high performance biodegradable adsorbent based on amylopectin and poly(acrylic acid) (AP-g-PAA) for removal of toxic malachite green dye (MG) from aqueous solution. The graft copolymer has been synthesized and characterized using various techniques including FTIR, GPC, SEM and XRD analyses. Biodegradation study suggests that the co-polymer is biodegradable in nature. The adsorbent shows excellent potential (Qmax, 352.11 mg g(-1); 99.05% of MG has been removed within 30 min) for removal of MG from aqueous solution. It has been observed that point to zero charge (pzc) of graft copolymer plays significant role in adsorption efficacy. The adsorption kinetics and isotherm follow pseudo-second order and Langmuir isotherm models, respectively. Thermodynamics parameters suggest that the process of dye uptake is spontaneous. Finally desorption study shows excellent regeneration efficiency of adsorbent.


Subject(s)
Acrylic Resins/chemistry , Amylopectin/chemistry , Coloring Agents/isolation & purification , Rosaniline Dyes/isolation & purification , Water Pollutants, Chemical/isolation & purification , Adsorption , Thermodynamics , Water Purification/methods
16.
Bioresour Technol ; 144: 485-91, 2013 Sep.
Article in English | MEDLINE | ID: mdl-23896441

ABSTRACT

The aim of this work is to study the feasibility of XG-g-PAM/SiO2 nanocomposite towards its potential application as high performance adsorbent for removal of Congo red (CR) dye from aqueous solution. The surface area, average pore size and total pore volume of the developed nanocomposite has been determined. The efficiency of CR dye adsorption depends on various factors like pH, temperature of the solution, equilibrium time of adsorption, agitation speed, initial concentration of dye and adsorbent dosage. It has been observed that the nanocomposite is having excellent CR dye adsorption capacity (Q0=209.205 mg g(-1)), which is considerably high. The dye adsorption process is controlled by pseudo-second order and intraparticle diffusion kinetic models. The adsorption equilibrium data correlates well with Langmuir isotherm. Desorption study indicates the efficient regeneration ability of the dye loaded nanocomposite.


Subject(s)
Coloring Agents/isolation & purification , Congo Red/isolation & purification , Nanocomposites/chemistry , Polysaccharides, Bacterial/chemistry , Silicon Dioxide/chemistry , Water Pollutants, Chemical/isolation & purification , Acrylic Resins/chemistry , Adsorption , Coloring Agents/chemistry , Congo Red/chemistry , Kinetics , Nanocomposites/ultrastructure , Solutions , Temperature , Time Factors
17.
Carbohydr Polym ; 95(2): 753-9, 2013 Jun 20.
Article in English | MEDLINE | ID: mdl-23648038

ABSTRACT

In recent years, wastewater treatment, especially for wastewaters which are not suitably recycled by conventional or normal biological processes, is getting more importance. Of late, natural biopolymer based flocculants are extensively used for wastewater treatment because of low cost, environment-friendly and easily availablility from reproducible farm and forest resources. This article introduces the development of a natural polymer based flocculant [amylopectin grafted with poly (acrylic acid) - AP-g-PAA] for treatment of synthetic effluent as well as mining industry wastewater. The graft copolymer based flocculants have been developed under optimum conditions and characterized using viscometry, (13)C NMR, SEM, TGA, rheological characteristics, determination of hydrodynamic radius and CHN analysis. The flocculation characteristics of grafted and ungrafted polysaccharide have been evaluated in synthetic effluents (as Fe-ore, kaolin, Mn ore suspensions) as well as in mining industry wastewater.


Subject(s)
Acrylic Resins/chemistry , Amylopectin/chemistry , Polymers/chemistry , Flocculation , Polymers/chemical synthesis
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