horseradish peroxidase was encapsulated in calcium alginate for the purpose of phenol removal. considering enzyme encapsulation efficiency, retention activity and enzyme leakage of the capsules, the best gelation condition was found to be 1 % w/v of sodium alginate solution and 5.5 % w/v of calcium chloride hexahydrate. upon immobilization, ph profile of enzyme activity changes as it shows high...

the chitosan nanoparticles used widely as a drug delivery systems recently. in the present study the echis carinataus snake venom loaded chitosan nanoparticles were prepared based on ionic gelation of tripolyphosphate and chitosan. the nanoparticles physicochemical characteristics, stability and biological activity of encapsulated venom were studied. the particles were spherical in shape and th...

Currently available polymers as a component of in-situ gels are unsuitable for treating high-temperature/high-salinity reservoirs due to their chemical and thermal degradation. In this study, a new copolymer-based gel system including high molecular weight nanostructured polymers (NSPs) was developed to address the excessive water production problem in reservoirs under harsh conditions. The sta...

2014 The gelification process by polycondensation leading to self similar clusters of polyurethane is studied, near and below the gelation threshold. In dilute solutions, where light scattering experiments are performed, the interaction between clusters is a function of 03B5, the distance to the gelation threshold. This is a direct evidence of the swelling of the clusters. Thus, the experimenta...

Motile extracts have been prepared from Dictyostelium discoideum by homogenization and differential centrifugation at 4 degrees C in a stabilization solution (60). These extracts gelled on warming to 25 degrees Celsius and contracted in response to micromolar Ca++ or a pH in excess of 7.0. Optimal gelation occurred in a solution containing 2.5 mM ethylene glycol-bis (beta-aminoethyl ether)N,N,N...

We study gelation in suspensions of model colloidal particles with short-ranged attractive and long-ranged repulsive interactions by means of three-dimensional fluorescence confocal microscopy. At low packing fractions, particles form stable equilibrium clusters. Upon increasing the packing fraction the clusters grow in size and become increasingly anisotropic until finally associating into a f...

bioedegradable nanoparticles are intensively investigated for their potential applications in drug delivery systems. being a biocompatible and biodegradable polymer, chitosan holds great promise for use in this area. this investigation was concerned with determination and optimization of the effective parameters involved in the production of chitosan nanoparticles using ionic gelation method. s...

In the slow-wave (SW) state, the vast majority of cortical neurons exhibit mostly synchronized oscillatory activity. In this study, we examined the right-left hemispheric difference in slow-wave timings in urethane-anesthetized mice. We found that interhemispheric cross-correlograms of local field potentials (LFPs) peaked asymmetrically. Double in vivo whole-cell patch-clamp recordings also rev...