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1.
Int J Biol Macromol ; 260(Pt 1): 129324, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38228210

RESUMO

In the rapidly evolving landscape of silver nanoparticles (Ag NPs) synthesis, the focus has predominantly been on plant-derived sources, leaving the realm of biological or animal origins relatively uncharted. Breaking new ground, our study introduces a pioneering approach: the creation of Ag NPs using marine fish collagen, termed ClAg NPs, and offers a comprehensive exploration of their diverse attributes. To begin, we meticulously characterized ClAg NPs, revealing their spherical morphology, strong crystalline structure, and average diameter of 5 to 100 nm. These NPs showed potent antibacterial activity, notably against S. aureus (gram-positive), surpassing their efficacy against S. typhi (gram-negative). Additionally, ClAg NPs effectively hindered the growth of MRSA biofilms at 500 µg/mL. Impressively, they demonstrated substantial antioxidant capabilities, out performing standard gallic acid. Although higher concentrations of ClAg NPs induced hemolysis (41.804 %), lower concentrations remained non hemolytic. Further evaluations delved into the safety and potential applications of ClAg NPs. In vitro cytotoxicity studies on HEK 293 and HeLa cells revealed dose-dependent toxicity, with IC50 of 75.28 µg/mL and 79.13 µg/mL, respectively. Furthermore, ClAg NPs affected seed germination, root, and shoot lengths in Mung plants, underscoring their relevance in agriculture. Lastly, zebrafish embryo toxicity assays revealed notable effects, particularly at 500 µg/mL, on embryo morphology and survival rates at 96 hpf. In conclusion, our study pioneers the synthesis and multifaceted evaluation of ClAg NPs, offering promise for their use as versatile nano therapeutics in the medical field and as high-value collagen-based nanobiomaterial with minimal environmental impact.


Assuntos
Nanopartículas Metálicas , Prata , Animais , Humanos , Prata/química , Nanopartículas Metálicas/química , Peixe-Zebra , Células HeLa , Staphylococcus aureus , Células HEK293 , Antibacterianos/farmacologia , Antibacterianos/química
2.
Chemosphere ; 271: 129415, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33460901

RESUMO

Elimination of heavy metals from wastewater has been a significant process to improve the aquatic source's quality. Various materials act as very effective adsorbents to remove heavy metals, which cause toxicity to plants and all other living organisms. Thus, the present work focuses on removing heavy metals chromium (Cr) and copper (Cu) ions containing wastewater using biodegradable and cost-effective chitosan-based hydrogel composite. The composite was prepared via chemical cross-linking of radical chitosan with polyacrylamide and N,N'-Methylene bisacrylamide and blended with orange peel. The synthesis of the adsorbent has been confirmed by using Fourier-transform infrared spectroscopy (FT-IR), Scanning electron microscopy - Energy dispersive X-ray analysis (SEM-EDAX) and X-ray diffraction (XRD) studies. The adsorption power of the composite of metal ions at different time, pH, adsorbent dosages, different metal ion concentrations were analyzed by using Atomic Absorption Spectroscopy (AAS). The results concluded that the optimum pH for Cr(VI) and Cu (II) were 4 and 5, contact time: 360 min, adsorbent dosage: 4 g, and initial metal ion concentration: 100 mg/L for each metal ions. The adsorption isotherm models follow the Freundlich model and pseudo-second-order kinetics. From the results, the adsorption capacity was observed to be 80.43% for Cr(VI) and 82.47% for Cu(II) ions, respectively.


Assuntos
Quitosana , Citrus sinensis , Poluentes Químicos da Água , Adsorção , Cromo/análise , Hidrogéis , Concentração de Íons de Hidrogênio , Íons , Cinética , Espectroscopia de Infravermelho com Transformada de Fourier , Águas Residuárias , Poluentes Químicos da Água/análise
3.
Int J Biol Macromol ; 104(Pt B): 1794-1806, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28807691

RESUMO

Chitosan (CS), an amino polysaccharide has fascinating scientific applications due to its many flexible properties. The advantages of Chitosan tend to increase when it was modified. Thus, in the present research work, to improve the properties of chitosan, it was converted into chitosan nanoparticles (CS-NPs) through the ionic gelation method using sodium tripoyphosphate (TPP) and sodium hexametaphosphate (SHMP) as a crosslinker. The size optimization was done by varying the parameters such as crosslinker concentration, agitation method and rate, agitation time, temperature and drying method. The prepared samples were characterized using FTIR, TGA, XRD, SEM, TEM and DLS. Also the prepared CS-NPs with TPP and SHMP had been evaluated in vitro for determining its hemocompatibility, biodegradability, serum stability, cytotoxicity and cell viability. The results showed the significant participation of all the parameters in obtaining the nanoparticles in 20-30nm and 5-10nm for CS-NPs-TPP air dried and freeze dried samples and around 60-80nm and 20-30nm for CS-NPs-SHMP air dried and freeze dried samples. The in vitro biological studies revealed that the nanoparticles are non-toxic with a good degree of biodegradability, blood compatibility and stability.


Assuntos
Materiais Biocompatíveis/química , Quitosana/química , Nanopartículas/química , Linhagem Celular Tumoral , Sobrevivência Celular , Liofilização , Humanos , Teste de Materiais , Estrutura Molecular , Nanopartículas/ultraestrutura , Tamanho da Partícula , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura , Termogravimetria , Difração de Raios X
4.
Int J Biol Macromol ; 104(Pt B): 1721-1729, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28363652

RESUMO

In the present work, a series of novel nanochitosan/cellulose acetate/polyethylene glycol (NCS/CA/PEG) blend flat sheet membranes were fabricated in different ratios (1:1:1, 1:1:2, 2:1:1, 2:1:2, 1:2:1, 2:2:1) in a polar solvent of N,N'-dimethylformamide (DMF) using the most popular phase inversion method. Nanochitosan was prepared by the ionotropic gelation method and its average particle size has been analyzed using Dynamic Light Scattering (DLS) method. The effect of blending of the three polymers was investigated using FTIR and XRD studies. FTIR results confirmed the formation of well-blended membranes and the XRD analysis revealed enhanced amorphous nature of the membrane ratio 2:1:2. DSC study was conducted to find out the thermal behavior of the blend membranes and the results clearly indicated good thermal stability and single glass transition temperature (Tg) of all the prepared membranes. Asymmetric nature and rough surface morphology was confirmed using SEM analysis. From the results it was evident that the blending of the polymers with higher concentration of nanochitosan can alter the nature of the resulting membranes to a greater extent and thus amorphous membranes were obtained with good miscibility and compatibility.


Assuntos
Celulose/análogos & derivados , Quitosana/química , Membranas Artificiais , Nanoestruturas/química , Polietilenoglicóis/química , Ultrafiltração , Varredura Diferencial de Calorimetria , Celulose/química , Espectroscopia de Infravermelho com Transformada de Fourier , Água/química , Difração de Raios X
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