Showing papers in "Journal of Controlled Release in 1996"

TL;DR: A threshold value of about 50% of TEER reduction has been identified, which allows for transport of hydrophilic compounds across the cell monolayers of the Caco-2 cell model.

TL;DR: Chitosan microspheres were prepared by a novel precipitation process using sodium sulfate as precipitant in this paper, and the extent of precipitation was controlled by the concentration of Sodium sulfate and monitored by turbidity measurement.

TL;DR: In this article, the authors used 3D printing for the fabrication of polymeric drug delivery systems, where the drug concentration profile is first specified in a computer model of the device which is then built using the 3DP process.

TL;DR: It is suggested that surface-modified NP should prove useful for the delivery of chemotherapeutic drugs to tumoral tissues by providing a protective barrier against extensive uptake by human monocytes, at least in plasma.

TL;DR: The movement of the penetrant and polymer fronts and the drug dissolution in highly loaded swellable matrix tablets showed that the difference between the diffusion and erosion fronts is decisive for the release kinetics, leading to a new finding that the distance between diffusion and eroded fronts is the most important parameter for drug release.

TL;DR: The polymeric micelle showed 1 8 to 1 5 cytotoxicity of intact cisplatin against murine B 16 melanoma cells during 24–72 h incubation, which suggests release of platinum complexes from the micelle.

TL;DR: Colon-specific drug delivery may be possible by the application of dried amylose films to pharmaceutical formulations byorporation of insoluble polymers into the amylOSE film, to controlAmylose swelling, of which a commercially available ethylcellulose (Ethocel®) was found to control the swelling most effectively.

TL;DR: The release of three model proteins from hydrogels varying in water content and degree of GMA-substitution was studied and it was shown that the release of the proteins was independent of the degree ofGMA substitution of gels at high equilibrium water contents.

TL;DR: There was little difference between the permeability of acetaminophen in Ca or Zn alginate gel films, and the decreased permeability was suggested to be due to increased cross-linking in the gelled structure.

TL;DR: A strong overlap has been identified between substrates for gut metabolism by cytochrome P-450 3A and gut counter-transport by P-glycoprotein, suggesting that these processes may work together to limit the bioavailability of a large number of drug substances.

TL;DR: The hydrogels synthesized in this study were capable of pulsatile streptokinase release, with at least one order of magnitude difference in release rates between the swollen and collapsed hydrogel states, but the much smaller heparin molecule diffused equally rapidly in the collapsed and swollen polymer states.

TL;DR: The peptide incorporation in low molecular weight hydrophilic polymers can be controlled by modification in the microsphere preparation process as mentioned in this paper, and the peptide not incorporated into the micro-sphere was extracted by the aqueous continuous phase during the micro sphere preparation.

TL;DR: This manuscript will focus on the physical and metabolic barrier functions of the intestinal mucosa, the structural features of peptides which influence their passive diffusion and carrier-mediated transport, including efflux mechanisms, and various approaches used to prevent enzymatic degradation of the peptides and increase their permeability across the intestine mucosa.

TL;DR: Approaches to effect the intracellular trafficking of a gene expression system to the nucleus of a target cell are described by using synthetic amphipathic peptides to control the endosomal release of plasmid DNA.

TL;DR: The results demonstrate the immunopotentiating properties of the biodegradable microspheres and their potential to elicit long-lasting immune responses after single administration when tailoring in vitro release characteristics and particle size.

TL;DR: In this article, aqueous emulsification process using either a temperature gradient (Tmp) or dilution (Dil) of the continuous phase (CP) of a salmon calcitonin (sCT)-loaded PLGA microspheres (size range 35-140μm) was described.

TL;DR: Azo-linked polymeric prodrugs of 5-aminosalicylic acid were prepared and evaluated in simulated human intestinal microbial ecosystem and it was demonstrated that for the hydrophobic polymer reduction stops at the hydrazine stage whereas for a hydrophilic analogue reduction with formation of amines occurred.

TL;DR: Investigation of the release properties of ABA block copolymers, which contain hydrophilic poly(ethylene oxide) B blocks, shows a continuous and molecular mass-dependent release, reminiscent of cross-linked hydrogels, which may offer advantages over PLG for parenteral protein delivery systems.

TL;DR: Iontophoretic drug delivery offers non-invasive, continuous and pulsatile delivery as well as preprogrammed complex dosing regimes and small battery powered wearable systems for peptide drugs are currently being developed.

TL;DR: Proteins have been released in vitro and in vivo, and locally released urokinase and tissue plasminogen activator have been demonstrated to further reduce postoperative adhesions relative to the gel barrier alone.

TL;DR: In this article, a polyethylene oxide (PEO) hydrogel was formed by crosslinking of aqueous PEO solutions of M n = 35 000, 900 000 and 5 000 000 in concentrations of 5-50% using γ-irradiation with 3-10 Mrad.

TL;DR: The possibilities of significantly improving oral bioavailability of poorly permeable drugs using seemingly acceptable excipients, including fatty acids, glyceride vehicles, and surfactants are demonstrated.

TL;DR: In this article, the scaleability of rotor/stator homogenization is limited by the internal circulation determined by the rotor and stator assembly, which is determined by shear forces generated in the turbulent zone between the spinning rotor and the stationary stator.

TL;DR: In this paper, the effect of a tertiary amine, namely caffeine, on the degradation of poly(dl -lactic acid) (PLA 50 ) matrix was examined in the presence of this basic compound on the hydrolytic cleavage of polyester chains.

TL;DR: A novel floating system based on ion exchange resins loaded with bicarbonate, which, on contact with media containing hydrochloric acid, release carbon dioxide causing the resin to float, was investigated and evaluated in vivo.

TL;DR: It was demonstrated using seven different drugs and one protein that the mechanism of release by the hydrogel matrix was a Fickian diffusion-controlled process, and it is believed that this family of BSA-PEG hydrogels could be useful for the preparation of controlled release devices in the field of wound dressing.

TL;DR: A model drug, theophylline, has been loaded onto the resin and this system gives a controlled release of drug, mediated by the coating, and has potential applications as acontrolled release gastric retentive system.

TL;DR: This work has shown that giant liposomes, containing microbial vaccines and other soluble antigens or cytokines if required, could be used as carriers of vaccines in cases where there is a need to prevent interaction of vaccines with maternal antibodies or preformed antibodies to vaccine impurities.

TL;DR: The enzyme modified by the branched polymer showed increased in vitro activity and proteolytic resistance, improved stability towards temperature and pH variations and enhanced half life, and data are in favour of the use of asparaginasemodified by the mPEG2 in the treatment of patients with tumour responding to this enzyme, in particular in case of intolerance to native asparagine.

TL;DR: High volatile fatty acid and carbon dioxide concentrations during in vitro fermentation studies showed that the formulation was susceptible to bacterial enzymatic attack, and dissolution release profiles of the formulation demonstrated in vitro gastric and small intestine resistance.