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2.
Environ Res ; 199: 111375, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34048745

RESUMO

The Lichen, Parmelia sulcata synthesizes various secondary metabolites, in which phenolic based compounds received much attention due to their importance in biomedical application. Especially the phenolic compound was effective against the cancer treatment. An effective administration of such plant natural product can represent a significant conventional management of cancer in terms of chemoprevention. The nanomedicines are group of agents that selectively interfere the cancer cells which leads to reduction of side effect thereby reducing the doses. Silver nanoparticles is a promising antitumor agent, however, the conventional production of silver nanoparticles have many drawbacks which led to increase in need of eco-friendly biological production methods. In this study, we made an attempt to synthesise a nano silver (Ps-AgNPs) from phenolic extract of lichen Parmelia sulcata extract. The Ps-AgNps was applied for anticancer activity using MCF-7 cells and the effect was characterised by western blotting method. The FTIR, XRD, UV and TEM results confirms the presence of silver nanoparticles in phenolic extract of lichen Parmelia sulcata. The cytotoxicity assay shows that the Ps-AgNPs is toxic against cancer cells (MCF-7) but not to normal cells (NIH3T3), which confirm the selective induction of cell death (apoptosis) against cancer cells. The Western blot analysis also clearly indicates the down regulation of inflammatory genes (TNF-alpha and IL-6) and cell cycle genes (PCNA and Cyclin-D1) thus promoting intrinsic apoptotic pathway. The results suggest that Ps-AgNPs can effectively kill cancer cells and can be used as an alternative therapeutic agent for cancer treatment.


Assuntos
Antineoplásicos , Nanopartículas Metálicas , Animais , Antibacterianos/farmacologia , Apoptose , Humanos , Células MCF-7 , Nanopartículas Metálicas/toxicidade , Camundongos , Células NIH 3T3 , Parmeliaceae , Extratos Vegetais/farmacologia , Prata/toxicidade
3.
Sci Rep ; 11(1): 5686, 2021 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-33707529

RESUMO

The present study focused on the synthesis of copper hydroxide nanowires decorated on activated carbon (Cu(OH)2-NWs-PVA-AC). The obtained Cu(OH)2-NWs-PVA-AC Nano-composite was distinguished by XRD, SEM, EDX, BET, FTIR and XPS respectively. Besides, different variables such as solution pH, and initial dye concentration, contact time, and temperature were performed on the adsorption efficiency of MB in a small batch reactor. Further, the experimental results are analyzed by various kinetic models via PFO, PSO, intra-particle diffusion and Elovich models, and the results revealed that among the kinetic models, PSO shows more suitability. In addition, different adsorption isotherms were applied to the obtained experimental data and found that Langmuir-Freundlich and Langmuir isotherm were best fits with the maximum adsorption capacity of 139.9 and 107.6 mg/g, respectively. The Nano-composite has outstanding MB removal efficiency of 94-98.5% with a span of 10 min. and decent adsorption of about 98.5% at a pH of 10. Thermodynamic constants like Gibbs free energy, entropy, and enthalpy were analyzed from the temperature reliance. The results reveal the adsorption processes are spontaneous and exothermic in nature. The high negative value of ΔG° (- 44.11 to - 48.86 kJ/mol) and a low negative value of ΔH° (- 28.96 kJ/mol) show the feasibility and exothermic nature of the adsorption process. The synthesized dye was found to be an efficient adsorbent for the potential removal of cationic dye (methylene blue) from wastewater within a short time.

4.
Int J Biol Macromol ; 168: 760-768, 2021 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-33232701

RESUMO

A novel, sustainable chitosan polymeric nanocomposite (CS-PVA@CuO) was synthesized and subjected to the removal of acid blue 25 (AB25) from the aqueous environment. The influence of different variables such as pH, contact time, initial dye concentration, temperature, and adsorption kinetics has been examined in the batch adsorption process. The CS-PVA@CuO composite was systematically characterized by XRD, FTIR, SEM, and EDX analysis. The pseudo-first order (PFO), pseudo-second order (PSO), and intra-particle diffusion kinetics equations were used to examine the kinetic data of the adsorption process. The adsorption kinetics confirms that the PSO model was a more exact fit. Thermodynamics study typically revealed that the uptake of AB25 by the adsorbent is spontaneous and endothermic in nature. Remarkably, the results reveal the highest adsorption capacity of the CS-PVA@CuO was 171.4 mg/g at 313 K. To be specific, CS-PVA@CuO polymer nanocomposite can be effectively used as a suitable adsorbent material for the potential elimination of anionic AB25 dye from the aqueous solutions.


Assuntos
Antraquinonas/isolamento & purificação , Quitosana/química , Poluentes Químicos da Água/isolamento & purificação , Adsorção , Concentração de Íons de Hidrogênio , Cinética , Nanocompostos , Polimerização , Termodinâmica
5.
Int J Biol Macromol ; 144: 85-93, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31838064

RESUMO

Use of biomaterial scaffolds as drug carriers for infected wounds treatment is of wide scope. A series of curcumin/TiO2 complex loaded chitosan scaffolds are fabricated for the same. Synthesized wound dressing material is screened for their morphology, water absorption capacity; in vitro drug release patterns, in vitro antibacterial studies against gram +ve and a gram -ve bacteria, cell viability for 3T3-L1 cell lines as well as in vivo MRSA infected wound healing capability. Formation of curcumin/TiO2 complex was confirmed by X-ray diffraction studies, the anchoring pattern of them on the chitosan scaffold was analyzed by FESEM and EDS mapping. All membranes showed a better performance towards in vitro antibacterial and in vivo wound healing properties than the control ones in 14 days. The bacterial count on wound for a regular time period was measured and the scaffold with higher amount of curcumin in its complex is found to give the better performance, along with skin regeneration due to synergistic effect of curcumin and TiO2.


Assuntos
Quitosana/química , Curcumina/farmacologia , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Pele/microbiologia , Têxteis , Alicerces Teciduais/química , Titânio/farmacologia , Cicatrização/efeitos dos fármacos , Células 3T3-L1 , Animais , Antibacterianos/farmacologia , Contagem de Colônia Microbiana , Curcumina/química , Liberação Controlada de Fármacos , Masculino , Membranas Artificiais , Staphylococcus aureus Resistente à Meticilina/crescimento & desenvolvimento , Camundongos , Testes de Sensibilidade Microbiana , Ratos Sprague-Dawley , Pele/efeitos dos fármacos , Titânio/química , Água , Difração de Raios X
6.
J Hazard Mater ; 369: 1-8, 2019 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-30753955

RESUMO

Moderate and eco-pleasing ion-exchange trade membranes are in need to recover acid from industrial waste. Present study is focused on incorporation of plant waste (Azadirachta indica, neem leaves powder (NP)) of different composition as filler to polysulfone (PSf) membrane matrix to achieve acid recovery. Membranes were characterized, their chemical, mechanical and thermal stabilities and effectiveness in acid recovery via diffusion has been inspected. Multi-functional groups (-COOH, -NH2, -OH, -OAc, -C = O) present in different components of NP contributes in their own means in H+ ion transportation through membrane in acid recovery. They assisted formation of hydrogen bond and provided channels for ion permeation, and facilitated selective transportation of H+ ion over Fe2+ ions and explained mechanism is in accordance with Grotthuss-type and vehicle mechanism. Membrane with 15% of NP showed better performance in terms of ion exchange capacity (IEC) and acid recovery, at optimum concentration of NP, composite the membrane showed highest IEC values of 3.9771 mmol/g, UH+ value of ≈46.499 × 10-3 m/h and greater separation factor ≈154, which is higher than commercially available DF-120 membrane. An original thought of utilizing NP in membrane matrix opens up promising opportunities for extremely straightforward, easy, cost-effective and greener methods of recovery acid.


Assuntos
Azadirachta , Ácido Clorídrico/química , Membranas Artificiais , Preparações de Plantas/química , Polímeros/química , Sulfonas/química , Poluentes Químicos da Água/química , Difusão , Compostos Ferrosos/química , Folhas de Planta , Pós , Reciclagem
7.
J Environ Manage ; 232: 372-381, 2019 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-30496967

RESUMO

This study investigates the removal of heavy metal ions and humic acid using Cellulose acetate (CA) and Poly (methyl vinyl ether-alt-maleic acid) (PMVEMA) blend membranes. Antifouling properties of blend membranes were also investigated. Flat sheet membranes were prepared by phase inversion technique using different concentrations of CA and PMVEMA. The prepared membranes were characterized and their performance was evaluated by measuring pure water flux, water uptake capacity and humic acid removal. Rejection of humic acid (HA) was observed to be around 97% for all the blend membranes because of electrostatic interactions between the functional groups of HA and blends. The fouling characteristics of the membranes was assessed using HA as a foulant and the antifouling capacity of blend membranes was observed to be greater with a flux recovery ratio of almost 95% when compared to bare CA, commercial CA (TechInc) and other reported CA blends used for HA rejection. Also, the blend membranes were very effective in removing heavy metal ions (Pb2+, Cd2+ and Cr+6) and humic acid simultaneously. Overall, the PMVEMA modified CA membranes can open up new possibilities in enhancing the hydrophilicity, permeability and antifouling properties.


Assuntos
Metais Pesados , Purificação da Água , Substâncias Húmicas , Íons , Membranas Artificiais
8.
J Hazard Mater ; 332: 112-123, 2017 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-28285104

RESUMO

Hydrophobic polysulphone (PSf) was reformed into a hydrophilic polymer by sulphonation (via electrophilic substitution) and was subsequently made into a composite by incorporating nano titania to reduce Cr (VI) in the concentrated feed to Cr (III), thus eliminating the hazards of Cr (VI). The modified polymer and its composites were characterized by spectroscopic and microscopic techniques. The composite membranes exhibited enhanced hydrophilicity and flux and were evaluated for the rejection of chromium. The effect of pH and interference of counter ions towards rejection was studied. The charges fixed on the surface of the membrane due to titania, support ionic interactions and facilitated the rejection process. Essentially, rejection of up to 98% was achieved. The innovation of using a bifunctional membrane for the rejection of Cr (VI) together with the removal of its toxicity by photocatalytic reduction, leading to the potential recovery of Cr (III), highlight the uniqueness of this work.

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