Preferential pi-pi complexation between tamoxifen and borage oil/gamma linolenic acid: transcutaneous delivery and NMR spectral modulation.

The effect of different proportions of borage oil on the in vitro transcutaneous delivery of tamoxifen were studied, with the aim of developing a gel capable of the simultaneous delivery of tamoxifen and gamma linolenic acid across (breast) skin. Supplementary work probed 1H NMR spectral data for tamoxifen in the presence of different proportions of polyunsaturated or unsaturated fatty acids. Typical, non-aqueous gels were modified to contain 1% tamoxifen and three levels of borage oil ( approximately 25% gamma linolenic acid) and the transcutaneous delivery of both tamoxifen and GLA across full thickness skin determined in vitro.

Effects of membrane type and liquid/liquid phase boundary on in vitro release of ketoprofen from gel formulations.

The aim of this study was to test the hypothesis that the most appropriate model for studying the diffusional release of an active from a topical formulation is one in which the membrane offers minimal resistance to release and involves a receptor phase that presents the least possible interfacial discontinuity. Using ketoprofen as the active, a series of simple gels were prepared consisting of PEG400 thickened with Cabosil M5. Using Franz-type diffusion cells, three different types of membrane (two porous and one non-porous) were compared, as were receptor phases of PEG400 (component of formulation) and PBS.

Ketoprofen: release from, permeation across and rheology of simple gel formulations that simulate increasing dryness.

The migration of ketoprofen through a series of simple gels that varied in solvent composition to simulate snapshots of a dynamically drying topical formulation was studied. Firstly, the release rate of ketoprofen was determined from formulations based on Cabosil and PEG 400, the proportion of which was varied to mimic progressively dryer states. Secondly, the apparent permeability of ketoprofen across the corresponding blank Cabosil gels was determined.

The in vitro delivery of NSAIDs across skin was in proportion to the delivery of essential fatty acids in the vehicle--evidence that solutes permeate skin associated with their solvation cages?

As part of our investigations into novel dual action topical anti-arthritis systems, the permeation of ibuprofen or ketoprofen plus eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) were determined from a fish oil vehicle across pig ear skin in vitro. The steady state fluxes of ibuprofen and ketoprofen were 9.17+/-1.