Microcapsules produced by interfacial polycondensation of p-phenylenediamine (PPD) and sebacoyl chloride (SC) were studied. The products were characterized in terms of morphology, mean diameter and effectiveness of dodecane encapsulation. The use of Tween 20 as dispersion stabilizer, in comparison with polyvinyl alcohol (PVA), reduced considerably the mean diameter of the microcapsules and orig...

The retention and adhesion of melamine formaldehyde (MF) microcapsules on a model fabric surface in aqueous solution were investigated using a customised flow chamber technique and atomic force microscopy (AFM). A cellulose film was employed as a model fabric surface. Modification of the cellulose with chitosan was found to increase the retention and adhesion of microcapsules on the model fabri...

A microcapsule-type self-healing protective coating with secondary crack preventing capability has been developed using a silanol-terminated polydimethylsiloxane (STP)/dibutyltin dilaurate (DD) healing agent. STP undergoes condensation reaction in the presence of DD to give a viscoelastic substance. STP- and DD-containing microcapsules were prepared by in-situ polymerization and interfacial pol...

Self-healing was achieved with a dual-microcapsule epoxy-amine chemistry in thermoset epoxy. One capsule contained a modified aliphatic polyamine (EPIKURE 3274) while the second capsule contained a diluted epoxy monomer (EPON 815C). Amine microcapsules were prepared by vacuum infiltration of EPIKURE 3274 into hollow polymeric microcapsules. Epoxy microcapsules were prepared by an in situ polyme...

In this study, microfluidic technology was employed to develop protein formulations. The microcapsules were produced with a biphasic flow to create water-oil-water (W/O/W) double emulsion droplets with ultrathin shells. Optimized microcapsule formulations containing 1% (w/w) bovine serum albumin (BSA) in the inner phase were prepared with poly(vinyl alcohol), polycaprolactone and polyethylene g...

Venlafaxine controlled drug delivery systems using different matrixes have been tested to reduce undesirable side effects in the treatment of depression. The legal status of chitosan (Cs) in Pharmacy has dramatically improved after its acceptance as excipient in several Pharmacopeias and, therefore, there is great interest in pharmaceutical formulations based on this polymer. In this paper, chi...

Intramuscular injection of [6-D-tryptophan]-luteinizing hormone-releasing hormone [( D-Trp6]LH-RH) in microcapsules of poly(DL-lactide-co-glycolide), designed to release a controlled dose of the peptide over a 30-day period, decreased the weights of androgen-dependent Dunning prostate tumors in rats and suppressed serum testosterone levels more effectively than daily subcutaneous administration...

Among various efficient cell culture systems, the encapsulation of living cells within alginate-poly-llysine (PLL) membrane has received much attention as a means of improving the production of desirable cellular products. This method, which was successfully demonstrated by Lim and Moss in 1979, was primarily developed to transplant living cells without an in oivo rejection reaction (Lim and Su...

Orally administrable alginate-poly-L-lysine-alginate (APA) microcapsules containing live yeast cells was investigated for use in renal failure. At all times, yeast cells remain inside the microcapsules, which are then excreted in the stool. During their gastrointestinal passage, small molecules, like urea, diffuse into the yeast microcapsules where they are hydrolyzed. Orally administrating the...

We investigated the encapsulation of BMP-2 gene-modified mesenchymal stem cells (MSCs) in alginate-poly-L-lysine (APA) microcapsules for the persistent delivery of bone morphogenic protein-2 (BMP-2) to induce bone formation. An electrostatic droplet generator was employed to produce APA microcapsules containing encapsulated beta-gal or BMP-2 gene-transfected bone marrow-derived MSCs. We found t...