hydrogels, due to their unique potentials such as high-water content and hydrophilicity are interest for the controlled release of drug molecules. the present study aims to create a controlled-release system through the preparation and characterization of hydrogels based on ph-sensitive polymers such as poly (acrylic acid). poly (acrylic acid), p(aa), hydrogel has been synthesized by radical po...

in the present work a ph-dependent cloud point extraction procedure using ph-sensitive hydrogel polymer was applied for preconcentration and spectrophotometric determination of the hg(ii) as its thio micher's ketone complex. central composite design (ccd) and response surface method were applied to design the experiments and find out the optimum conditions. four factors entitled concentration o...

Hydrogels, due to their unique potentials such as high-water content and hydrophilicity are interest for the controlled release of drug molecules. The present study aims to create a controlled-release system through the preparation and characterization of hydrogels based on pH-sensitive polymers such as poly (acrylic acid). Poly (acrylic acid), p(AA), hydrogel has been synthesized by radical po...

A novel pH-responsive superabsorbent hydrogel based on gelatin was prepared through crosslinking copolymerization of poly (acrylic acid) and poly (itaconic acid). The copolymerization conditions including monomers, initiator, gelatin and crosslinker concentration, reaction temperature, and neutralization percent were systematically optimized to achieve a hydrogel with swelling capacity as high ...

We report fabrication and characterization of a new hydrogel-based microsensor for wireless chemical monitoring. The basic device structure is a high-sensitivity capacitive pressure sensor coupled to a stimuli-sensitive hydrogel that is confined between a stiff porous membrane and a thin glass diaphragm. As small molecules pass through the porous membrane, the hydrogel swells and deflects the d...

We use instrumented indentation to characterize the mechanical and transport behavior of a pH-sensitive hydrogel in various aqueous buffer solutions. In the measurement, an indenter is pressed to a fixed depth into a hydrogel disk and the load on the indenter is recorded as a function of time. By analyzing the load–relaxation curve using the theory of poroelasticity, the elastic constants of th...

The deformation behavior of a pH-sensitive hydrogel micro-fluidic valve system is investigated using inhomogeneous gel deformation theory, in which the fluid-structure interaction (FSI) of the gel solid and fluid flow in the pipe is considered. We use a finite element method with a well adopted hydrogel constitutive equation, which is coded in commercial software, ABAQUS, to simulate the hydrog...

The alginate-based hydrogel was prepared as a pH-sensitive drug delivery system. To enhance the drug loading capacity, activated carbon was introduced as a drug absorbent. The iron oxide was incorporated into the alginate matrix for the magnetic transferring to the target organ. The activated carbon and iron-oxide were dispersed uniformly in the alginate hydrogel. The drug release from the algi...