Improving topical non-melanoma skin cancer treatment: In vitro efficacy of a novel guanosine-analog phosphonate.

Actinic keratosis, a frequent carcinoma in situ of non-melanoma skin cancer (NMSC), can transform into life-threatening cutaneous squamous cell carcinoma. Current treatment is limited due to low complete clearance rates and asks for novel therapeutic concepts; the novel purine nucleotide analogue OxBu may be an option. In order to enhance skin penetration, solid lipid nanoparticles (SLN, 136-156 nm) were produced with an OxBu entrapment efficiency of 96.

Drug release and skin penetration from solid lipid nanoparticles and a base cream: a systematic approach from a comparison of three glucocorticoids.

Solid lipid nanoparticles (SLNs) can enhance drug penetration into the skin, yet the mechanism of the improved transport is not known in full. To unravel the influence of the drug-particle interaction on penetration enhancement, 3 glucocorticoids (GCs), prednisolone (PD), the diester prednicarbate (PC) and the monoester betamethasone 17-valerate (BMV), varying in structure and lipophilicity, were loaded onto SLNs. Theoretical permeability coefficients (cm/s) of the agents rank BMV (-6.

Interaction of drug-carrier systems with targets--a study using atomic force microscopy.

To learn about the interaction between drug agents and nanoparticular carrier systems, the physical analytical methods of parelectric, electron spin and fluorescence spectroscopy have proven helpful tools to yield descriptive models of such complex systems. For a deeper understanding of drug absorption from body surfaces and drug distribution into the tissues, however, the lack of knowledge about the interaction between such agents and membranes on different levels is a severe drawback. This gap can be closed by the application of atomic force microscopy at normal temperatures and under the admission of liquid surroundings.

Reconstructed epidermis and full-thickness skin for absorption testing: influence of the vehicles used on steroid permeation.

A protocol for percutaneous absorption studies has been validated, based on the use of reconstructed human epidermis (RHE) and aqueous solutions of test substances. However, it is often the case that it is more-complex formulations of drugs or chemicals which will make contact with the skin surface. To investigate whether RHE and the reconstructed full-thickness skin model (FT-model) can be used to predict uptake from formulations, we compared the permeation of hydrocortisone and testosterone when applied in emulsion form and as a solution containing the penetration enhancer, ethanol.

Cyclosporine-loaded solid lipid nanoparticles (SLN): drug-lipid physicochemical interactions and characterization of drug incorporation.

Solid lipid nanoparticles (SLN) were produced loaded with cyclosporine A in order to develop an improved oral formulation. In this study, the particles were characterized with regard to the structure of the lipid particle matrix, being a determining factor for mode of drug incorporation and drug release. Differential scanning calorimetry (DSC) and wide-angle X-ray scattering (WAXS) measurements were employed for the analysis of the polymorphic modifications and mode of drug incorporation.