Synthesis, characterization and electrial properties of poly N-Phenyl 2-Naphthyl amine and poly N-Ethyl aniline

Poly n-phenyl-2-naphthyl amine [PNPNA] and poly N-ethyl aniline [PNEA] have been prepared using potassium persulphate as an oxidizing agent. The polymers were characterized by various methods using spectrophotometric measurements, e.g., I.R. and UV-visible. Thermal gravimetric analysis [TGA] for PNEA indicated its great thermal stability up to 430 degree. A.C. resistivity and capacitance measurements have been used to characterize the electrical properties of the prepared polymers in the temperature ranges from 25 degree to 160 degree for and from 25 degree to 240 degree for PNEA. Log p, capacitance, Ea and dielectric constant values were obtained at different frequency ranges from 5OHz up to 100 kHz. The results suggest hopping conduction mechanism for the PNPNA pellets, the increase in conductivity being governed by the interchain hopping of polarons acting as charge carriers. The PNEA pellets, on the other hand, showed higher resistivity values at all frequency ranges than those of PNPNA. Also the A.C. resistivity tends to become temperature independent. Accordingly, the conductivity increased with increasing frequency. This behaviour is attributed to the presence of ethyl groups in the polymer chain that introduce new trap levels within the localized states

Basic aminopeptidase from rabbit kidney: purification and partial characterization

The aminopeptidase activity of a homogenate of rabbit kidney treated with Triton X-100 was measured using L-aminoacyl-2-naphthylatmides (AA-NA). After gradient elution ion-exchange chromatography, four peaks of aminopeptidase activity were eluted. The enzyme eluted at 450 muS containing 33.5 per cent of the activity towards Arg-NA was applied to a Superdex 75 column and presented only one protein band on 10 per cent SDS-polyacrylamide gel electrophoresis. This enzyme has an apparent molecular mass of 78 kDa, is five-fold activated by 0.15 M NaCl and the highest Vmax/Km ratio was obtained with Arg-NA. Enzyme activity was inhibited 100 per cent by 0.13 mM sodium p-hydroxymercuribenzoate, 20 per cent by 0.75 mM EDTA and 100 per cent by 0.66 mM ophenanthroline. Puromycin and bestatin behaved like competitive inhibitors with a Ki of 0.60 mM and 5.0 muM, respectively.