RESUMO
In this study, green synthesis of gold nanoparticles (AuNPs) was performed by a sunlight irradiation method using the Borassus flabellifer fruit extract as a reducing agent. 5-Fluorouracil (5-FU)-loaded GG capped AuNPs (5FU-G-AuNPs) was prepared. The nanoparticles was further characterised by UV-visible spectra, particle size analysis, zeta potential, SAED, HRTEM, and XRD. The MTT assay results showed the suitability 5-FU-G-AuNPs. In this study, 5-FU-G-AuNPs exhibited potential cytotoxic and apoptotic effects on (MiaPaCa-2) cell line.
Assuntos
Portadores de Fármacos/síntese química , Fluoruracila/administração & dosagem , Ouro/química , Nanopartículas Metálicas/química , Neoplasias Pancreáticas/tratamento farmacológico , Antineoplásicos/administração & dosagem , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Portadores de Fármacos/química , Composição de Medicamentos/métodos , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Fluoruracila/farmacocinética , Química Verde , Humanos , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Extratos Vegetais/químicaRESUMO
Keratins as fibrous proteins, offer structural integrity to various tissues in providing the functional role of protection or load bearing. This work is a prelude to understand the structure - property correlation for a wide variety of keratins. The kinetics of aggregation of bovine hoof keratin (KF) and horn keratin (KR) were monitored by different biophysical methods. pH dependent studies indicated that initially both keratins existed in pre-aggregated form and the efficiency of aggregation decreased with increasing pH. The size of the aggregates was found to be larger in KF compared to KR. UV-vis and particle size analysis clearly revealed that the pre-aggregated forms of KF and KR dissociated to intermediate transient structures with smaller aggregate size, which acted as stronger nucleating agents for further self association of the keratins to form higher order supramolecular assemblies. Conformational analysis indicated that there was no significant conformational change during the aggregation of KF and KR. Morphology of the KF aggregates showed fractal arrangement while KR aggregates formed an ordered structure with no particular arrangement. To the best of our knowledge, this is the first report which shows an interesting and unique observation on changes in the structure during self-association of keratins.
Assuntos
Casco e Garras , Cornos , Queratinas/química , Agregados Proteicos , Animais , Bovinos , Concentração de Íons de Hidrogênio , Queratinas/metabolismo , Cinética , Tamanho da Partícula , Estrutura Secundária de Proteína , Relação Estrutura-AtividadeRESUMO
Understanding the mechanism of stabilization of collagen is an important area of research. Metal ions are known to interact with collagen and bring about the stability of the same. In the present investigation, the interaction of zirconium(IV) complexes with collagen was studied. The effect of zirconium(IV) complexes, namely zirconium oxychloride and zirconium oxalate on the enzymatic and thermal stability of collagen was investigated. Zirconium has been found to increase the hydrothermal stability of the rat tail tendon (RTT) collagen fibers to about 8-10 degrees C more than that of the native collagen. The order of stabilization of zirconium(IV) complexes is zirconium oxychloride>zirconium oxalate. This could be due to the differences in the type of interaction with collagen, which is also reflected in the differences in the conformational changes of collagen brought about by the two complexes. Zirconium oxychloride, which forms tetrameric species in solution, has been shown to have better crosslinking with collagen as seen from viscometry studies and hence provides better enzymatic stability to collagen than zirconium oxalate, which largely forms monomeric species in solution.