using ion-exchange resins, a multiple-unit type of oral floating dosage system has been prepared to prolong gastric emptying time of dosage form. the system is composed of beads of drug-resin complex, which are loaded with bicarbonate ions and coated with a hydrophobic polymer. the system is so designed that when the beads reach the stomach, chloride ions are exchanged with bicarbonate and drug...

Preliminary work by paper and thinlayer chromatography have indicated the existence of a number of similar antagonists with different specific activity. In the earlier stage of the purification, it was studied whether the minor components were real or artifacts. We found it convenient to use buffered resin chromatography according to the procedure of Moore et al.2) for the separation of detoxin...

The Merrifield solid-phase peptide synthesis technique has been adapted to the synthesis of homo- and heterometallic metal−organic complex arrays (MOCAs). A terpyridine-appended and Fmoc-protected L-tyrosine derivative was metalated with Pt(II), Rh(III), or Ru(II) ions in solution and sequentially coupled at the surface of functionalized polymeric resin to give a metal complex triad (Rh−Pt−Ru),...

Binding resin beads used in DGT (diffusion gradients in thin films) tend to settle to one side of the resin during casting. This phenomenon might be relevant for metal accumulation when partially labile complexes dominate the metal speciation, especially after recognizing the important role played by complex dissociation in the resin domain. The influence of the inhomogeneity of the binding age...

Complexes of ion-exchange resins and dextromethorphan (DM), a model drug, were prepared using different methods including a batch and a column method with different functional groups, ion-exchange capacity, degree of crosslinking, and resin particle size. Drug loading efficiency, release profiles, and scanning electron micrographs were also investigated. Most of the functional groups of resins ...

Interactions between poly(ethy1ene oxide) and phenol-formaldehyde resin play important roles in the mechanism by which the two polvmers improve fibre retention in the papermaking process. These were investigated at the concentration level and shear conditions found in this vrocess. The results indicste that the comvlex formed varies with pH and ionic strength over a very narrow range of conditi...

Propolis, a honeybee product, has gained popularity as a food and alternative medicine. Its constituents have been shown to exert pharmacological effects, such as anti-microbial, anti-inflammatory and anticancer. Shoot apices of Baccharis dracunculifolia (alecrim plant, Asteraceae) have been pointed out as sources of resin for green propolis. The present work aimed (i) to observe the collecting...

A review of paint hazards is made, giving brief descriptions of methods of application in use in 1965, of paint usage according to resin base, and of paint ingredients. The most interesting and complex of these are the resin bases, which have much in common with plastics. Reference is made to some of the many minor ingredients. The problem of keeping abreast of the possible toxic effects, so th...

This research was undertaken with an aim to formulate dextromethorphan hydrobromide as extended release micropellets. The Preformulation studies were carried out on drug Dextromethorphane Hydrobromide and it shows that Drug has good flow property. Various ion exchange resins screened for complexation the ratio of drug: resin optimized along manufacturing process complexation. Drug-Resin complex...