Ketotifen controlled release from cellulose acetate propionate and cellulose acetate butyrate membranes

Abstract

Ketotifen was immobilised in cellulose acetate propionate (CAP) membranes and in cellulose acetate butyrate (CAB) membranes. The characteristics of each system were evaluated under a range of experimental conditions. The topography and uniformity of the membranes was assessed using scanning electron microscopy. The release characteristics associated with Ketotifen were monitored spectrophotometrically. The swelling capacity of the membranes was evaluated and attributed to the combined effects of diffusion and of complex dissociation, during swelling. The materials produced were able to provide controlled release of Ketotifen due to their controlled swelling behaviour and adequate release properties. The results showed that the release of Ketotifen from the CAB membranes is higher but the release from the CAP membranes is more uniform.

A New Nonconjugated Naphthalene Derivative ofMeso‐tetra‐(3‐hydroxy)‐phenyl‐porphyrin as a Potential Sensitizer for Photodynamic Therapy

“…In fact, in vitro studies showed that NAF participates actively in the formation of reactive oxygen species, having a toxic effect on cells (11,12). Following our previous work on medicinal chemistry (13–15) and PDT (16,17), we have designed a new macrocyclic molecule with the expectation that, by connecting both porphyrin and NAF characteristics, we may obtain a good PDT effect, through the possibility of two different modes of excitation, arising from the porphyrin macrocycle and the peripheral naphthyl groups, therefore improving the therapeutic response for the same molar doses. As with the related meso tetra‐(4‐( N ‐methyl‐ N ‐9‐anthracenyl‐methyl)‐sulfamoylphenyl)‐porphyrin (18), both singlet and triplet energy transfer pathways exist from the naphthalene moieties to the porphyrin.…”

Ternary mutual diffusion of isoniazid in aqueous sodium chloride, sodium hydroxide, and hydrochloric acid at T=298.15K

“…Therefore, it is necessary to improve the efficiency of these drug administration, transport, and release. Following our own studies in medicinal chemistry [3][4][5][6][7][8][9][10][11], namely in the development of new antituberculosis drugs of the pyrazine family [12], we undertook a series of studies concerning the diffusion behaviour of isoniazid in complex systems. The exact knowledge of those thermodynamic parameters is a prerequisite to obtain systems with safer and effective drug formulations.…”

Transport properties of aqueous solutions of sodium alginate at 298.15K

“…Following our own previously studies on the application of molecular simulation to organic solutions of poly-electrolytes to food and medicinal chemistry (Cardoso et al, 2008;Sobral, Sobral, Guthrie, & Gil, 2008;Silva, Paixão, Beja, Justino, & Sobral, 2006;, we report here the use of computational tools for a comparative experimental/ theoretical interpretation of alginate and caffeine interactions in an aqueous solution.…”