capacities of the hydrogels were found to be 500-1500 mg Fe(3+) g(-1) and 1500-2500 mg Fe(2+) g(-1) Copanlisib supplier for PAAm and PAAm/DHBA hydrogels, respectively, depending on the pH of the media. The selectivity of the conjugate hydrogel toward ferric ions was studied at several different pH values. At every pH ranging from 2 to 7.5, the conjugate hydrogel showed relatively high binding affinity for ferric ions. The selective and rapid, high affinity binding of iron by this siderophore-mimetic hydrogel offers potential application as a nonabsorbed chelator for iron in the gastrointestinal tract of patients suffering from iron overload diseases. (C) 2011 Wiley Periodicals, Inc. J Appl Polym Sci 121: 1384-1392, 2011″
“The aim of this study was to develop a novel nanoparticulate
formulation and test its potential for oral peptide drug delivery. Chitosan-6-mercaptonicotinic acid is a novel thiolated chitosan with strong mucoadhesive properties. Nanoparticles were developed by an ionic gellation method. The obtained particles were characterized in terms of mucoadhesion, stability, toxicity, and in vitro release. Human insulin (HI) was chosen as a model peptide drug, incorporated in the particles and orally administered to rats. Human insulin was quantified in the blood by means of ELISA. The size of the obtained particles was in selleckchem the range of 200-300 nm and the zeta potential was determined to be +8-+23 depending on the amount of thiol groups attached on the polymer. After 3 h of incubation up to 60% of the thiolated chitosan nanoparticles remained attached to the mucosa in contrast to 20% of unmodified chitosan particles. The AUC of HI after oral administration of thiolated chitosan nanoparticles was 4-fold improved compared to unmodified chitosan nanoparticles. Due to these improvements, check details chitosan-6-mercaptonicotinic acid nanoparticles are promising vehicles for oral delivery of peptide drugs.”
“A porous polysiloxane
has been chemically modified with a functional C,C-bibyrazolic ligand using the heterogeneous route. This synthetic route involved the reaction of 3-glycidoxypropyltrimethoxysilane silylant agent, previously anchored on a silica surface, with C,C-bipyrazolic ligand. The new modified polysiloxane (SiL) has been characterized by elemental analysis and infrared spectra and was studied and evaluated by determination of the surface area using the BET equation, the adsorption and desorption capability using the isotherm of nitrogen and B.J.H. Pore sizes. The new inorganic-organic polymer exhibits good thermal stability determined by thermogravimetry curves and good chemical stability examined in various acidic and buffer solutions. The solid was utilized in batch method for separation and trace extraction of (Hg(2+), Cd(2+), Pb(2+), and Cu(2+)) and compared with the results of classical liquid-liquid extraction with the unbound C,C-bipyrazole compound.