RESUMO
This report describes a novel carboxyl pendant containing adenylated polymeric template, its metalation with Zn (II), and manifestation of catalytic activity for the hydrolysis of model phosphodiester, bis(p-nitrophenyl) phosphate (bNPP), and plasmid cleavage. Observation of a bell-shaped pH-K(obs) profile suggested influence of pH variation over hydrolysis rate. This metalated polymer also afforded facile relaxation of pBR322 supercoiled DNA, with an interesting reusability feature intricately associated with heterogeneous catalysis.
Assuntos
Adenina/química , Ésteres/química , Polímeros/síntese química , Zinco/química , Catálise , DNA Super-Helicoidal/química , Dimerização , Concentração de Íons de Hidrogênio , Hidrólise , Cinética , Modelos Moleculares , Polímeros/química , Fatores de TempoRESUMO
This manuscript describes one-pot, in situ synthesis of organoapatite-gold nanoparticle composite and its characterization by XRD, energy dispersive X-ray analysis, atomic force, and scanning electron microscopy. This methodology offers a different approach into the synthesis of zerovalent metal-mineral-phase nanocomposites having potential application as osteointegrative ceramics.
Assuntos
Biomimética , Durapatita , Ouro/química , Cristalização , Durapatita/síntese química , Durapatita/química , Estrutura Molecular , Tamanho da Partícula , Propriedades de SuperfícieRESUMO
An opacified intraocular lens explanted from a patient in the postoperative period after phacoemulsification was investigated to find the cause of opacification. From the UV-visible and energy dispersive X-ray spectroscopy (EDS) measurements, the opacification in the present case seems to be due to calcification of the intraocular lens and not due to modification in the UV absorber material of the lens. The average free volume size of the intraocular lens both in unimplanted and explanted state were obtained from positron lifetime spectroscopy (PLS). Further, the combined FTIR and PLS results indicate that calcium gets into the free volume cavities of the intraocular lens matrix as a cationic moiety, may be in the form of Ca(++). The small decrease in glass transition temperature of the calcified lens seems to indicate the plasticizing action of calcium ions. The present results could be of some use in the design of the intraocular lens material in which calcification would be minimum.
Assuntos
Calcinose/etiologia , Extração de Catarata , Lentes Intraoculares , Cálcio/farmacologia , Vidro/química , Humanos , Espectroscopia de Infravermelho com Transformada de Fourier , Análise Espectral , TemperaturaRESUMO
An investigation of various variables in 100 para-suicide patients admitted to Wigan and Leigh Group of Hospitals was carried out. The subject's age, sex, religion, social class, type of residence, previous treatment received, etc., were examined in detail.
