Abstract. The aim was to develop niosomal gel as a transdermal nanocarrier for improved systemic availability of lopinavir. Niosomes were prepared using thin-film hydration method and optimized for molar quantities of Span 40 and cholesterol to impart desirable characteristics. Comparative evaluation with ethosomes was performed using ex vivo skin permeation, fluorescence microscopy, and histopathology studies. Clinical utility via transdermal route was acknowledged using in vivo bioavailability study in male Wistar rats. The niosomal formulation containing lopinavir, Span 40, and cholesterol in a molar ratio of 1:0.9:0.6 possessed optimally high percentage of drug entrapment with minimum mean vesicular diameter. Ex vivo skin permeation studies of lopinavir as well as fluorescent probe coumarin revealed a better deposition of ethosomal carriers but a better release with niosomal carriers. Histopathological studies indicated the better safety profile of niosomes over ethosomes. In vivo bioavailability study in male Wistar rats showed a significantly higher extent of absorption (AUC 0→∞ , 72.87 h×μg/ml) of lopinavir via transdermally applied niosomal gel as compared with its oral suspension. Taken together, these findings suggested that niosomal gel holds a great potential of being utilized as novel, nanosized drug delivery vehicle for transdermal lopinavir delivery.

The present study investigates the preparation of celecoxib-loaded albumin microspheres and the biodistribution of technetium-99m ((99m)Tc)-labeled celecoxib as well as its microspheres after intravenous administration. Microspheres were prepared using a natural polymer BSA using emulsification chemical cross-linking method. The prepared microspheres were characterized for entrapment efficiency, particle size, and in vitro drug release. Surface morphology was studied by scanning electron microscopy. Biodistribution studies were performed by radiolabeling celecoxib (CS) and its microspheres (CMS) using (99m)Tc and injecting arthritic rats intravenously. The geometric mean diameter of the microspheres was found to be 5.46 microm. In vitro release studies indicated that the microspheres sustained the release of the drug for 6 days. Radioactivity measured in different organs after intravenous administration of celecoxib solution showed a significant amount of radioactivity in the liver and spleen. In case of celecoxib-loaded microspheres, a significant amount of radioactivity accumulated in the lungs. No significant difference (P > .1) in the radioactivity was observed between the inflamed joint and the noninflamed joint following intravenous injection of (99m)Tc-CS. However, in case of the microspheres (CMS), the radioactivity present in the inflamed joint was 2.5-fold higher than in the noninflamed joint. The blood kinetic studies revealed that celecoxib-loaded albumin microspheres exhibited prolonged circulation than the celecoxib solution.

Voice bulletin boards may be an effective method of providing support to mothers who have a history of drug use. Use of these services may lead to lower cost without worsening patients' health.

Background:Olmesartan medoxomil (OLM), an anti-hypertensive agent administered orally has absolute bioavailability of only 26% due to the poor aqueous solubility (<7.75 μg/ml). The present investigation aimed at enhancing the oral bioavailability of OLM by improving its solubility and dissolution rate by preparing nanosuspensions.Materials and methods:The nanosuspensions of OLM were prepared using media milling technique followed by its lyophilization using mannitol as a cryoprotectant. Various formulation as well as process parameters were optimized in order to achieve desirable size and saturation solubility. Characterization of the prepared nanosuspension was done with respect to particle size, zeta potential, saturation solubility, dissolution rate, morphology study (TEM), in-vitro and exvivo drug diffusion study. Evaluation of the crystalline state before and after particle size reduction was done by differential scanning calorimetry (DSC) and powder X-ray diffraction (PXRD).Results:The results indicated that the initial crystalline state is preserved following particle size reduction and that the saturation solubility, dissolution velocity and diffusion rate of the drug from the nanosuspension is significantly higher than that of the plain drug suspension as well as from the marketed tablet formulation.Conclusion:Nanosuspension seems to be a promising approach for bioavailability enhancement because of the simple method of its preparation and its universal applicability.