HPLC-UV analytical validation of a method for quantification of progesterone in ex vivo trans-corneal and trans-scleral diffusion studies.

Progesterone (PG) diminishes free radical damage and thus can afford protection against oxidative stress affecting the retina. The therapeutic use of PG is limited because it is a highly hydrophobic steroid hormone with very low solubility in water. This is the main drawback for the therapeutic application of PG at ocular level. The aims of this study were: (i) to analyze if PG causes ocular irritation (ii) to validate a HPLC method to determine PG in ex vivo studies and (iii) to evaluate PG permeation through cornea and sclera. A high performance liquid chromatographic method was developed and validated to detect PG incorporated to ß-cyclodextrin using a Waters Sunfire C18 (150 × 4.6 mm) reverse-phase column packed with 5 µm silica particles using a mobile phase consisted of a mixture of acetonitrile (ACN) and pure water 80:20 (v/v), pH 7.4. The limit of detection and the limit of quantification for 50 µL injection of PG were found to be 0.42 and 1.26 µg/mL, respectively. The calibration curve showed excellent linearity over the concentration range (0.5 µg/mL to 100 µg/mL). As proof of concept, ex-vivo experiments to investigate PG permeation through cornea and sclera with vertical diffusion cells were carried out to quantify PG diffusion. Ex vivo experiments demonstrate its applicability to investigate permeation levels of PG from 6.57 ±â€¯0.37 µg/cm2 at cornea and 8.13 ±â€¯0.85 µg/cm2 sclera. In addition, at the end of diffusion studies the amount of PG retained in each tissue was also quantified, and it was 40.87 ±â€¯9.84 µg/cm2 (mean ±â€¯SD; n = 6) in cornea and 56.11 ±â€¯16.67 µg/cm2 (mean ±â€¯SD; n = 6) in sclera.

Anti-angiogenic drug loaded liposomes: Nanotherapy for early atherosclerotic lesions in mice.

Fumagillin-loaded liposomes were injected into ApoE-KO mice. The animals were divided into several groups to test the efficacy of this anti-angiogenic drug for early treatment of atherosclerotic lesions. Statistical analysis of the lesions revealed a decrease in the lesion size after 5 weeks of treatment.

Comparing metoclopramide electrotransport kinetics in vitro and in vivo.

The purpose of this work was to investigate the transdermal iontophoretic delivery of metoclopramide and to determine (i) the dependence of electrotransport on current density and drug concentration, (ii) the relative contributions of electromigration and electroosmosis and (iii) the feasibility of administering therapeutic amounts of drug, using a drug-sparing iontophoretic configuration. Iontophoretic delivery of metoclopramide (MCL) across dermatomed porcine ear skin was investigated in vitro as a function of concentration (10, 20, 40, 80 and 100mM) and current density (0.1, 0.2 and 0.3mAcm(-2)) using vertical flow-through diffusion cells. In vivo studies were performed in Wistar rats (40mM MCL, 0.3mAcm(-2), 5h); the anodal and drug formulation compartments were separated by a salt bridge. Cumulative delivery in vitro after 7h of current application (40mM MCL; 0.3mAcm(-2)) in the absence of electrolyte was 624.45+/-99.45microgcm(-2) (flux - 2.55+/-0.35microgcm(-2)min(-1)). There was a linear relationship between flux and both current density and drug concentration. Co-iontophoresis of acetaminophen confirmed that electromigration was the major transport mechanism (accounting for approximately 80% of MCL delivery). Electroosmotic inhibition, albeit modest, was only observed at the highest MCL concentration (100mM). Although the delivery rate observed in vivo in male Wistar rats (1.21+/-0.55microgcm(-2)min(-1)) was lower than that observed in vitro, the results suggest that drug input rates would be sufficient to achieve therapeutic levels in humans using non-invasive transdermal iontophoresis.