Self-Emulsifying Drug Delivery Systems (SEDDS): Measuring Energy Dynamics to Determine Thermodynamic and Kinetic Stability.

This research was designed to identify thermodynamically and kinetically stable lipidic self-emulsifying formulations through simple energy dynamics in addition to highlighting and clarifying common ambiguities in the literature in this regard. Proposing a model study, this research shows how most of the professed energetically stable systems are actually energetically unstable, subjected to indiscriminate and false characterization, leading to significant effects for their pharmaceutical applications. A self-emulsifying drug delivery system (SEDDS) was developed and then solidified (S-SEDDS) using a model drug finasteride. Physical nature of SEDDS was identified by measuring simple dynamics which showed that the developed dispersion was thermodynamically unstable. An in vivo study of albino rats showed a three-fold enhanced bioavailability of model drug with SEDDS as compared to the commercial tablets. The study concluded that measuring simple energy dynamics through inherent properties can distinguish between thermodynamically stable and unstable lipidic systems. It might lead to correct identification of a specific lipidic formulation and the application of appropriate characterization techniques accordingly. Future research strategies include improving their pharmaceutical applications and understanding the basic differences in their natures.

Nanocrytals-Mediated Oral Drug Delivery: Enhanced Bioavailability of Amiodarone.

The aim of this study was to improve the saturation solubility, dissolution profile and oral bioavailability of amiodarone hydrochloride (AMH), a highly lipophilic drug. Stabilizer (Pluronic F-127)-coated AMH nanocrystals (AMH-NCs) were developed by a combination of antisolvent precipitation and homogenization techniques. The optimized formulation comprised pluronic F-127 and AMH at the concentration of 4% and 2% w/v, respectively. The particle size (PS), zeta potential (ZP) and polydispersity index (PDI) of the optimized formulation was found to be 221 ± 1.2 nm, 35.3 mV and 0.333, respectively. The optimized formulation exhibited a rough surface morphology with particles in colloidal dimensions and a significant reduction in crystallinity of the drug. AMH-NCs showed a marked increase in the saturation solubility as well as rapid dissolution rate when compared with the AMH and marketed product. The stability study displayed that the formulation was stable for 3 months, with no significant change in the PS, ZP and PDI. The in vivo pharmacokinetic study demonstrated the ability of AMH-NCs to significantly (p < 0.05) improve the oral bioavailability (2.1-fold) of AMH in comparison with AMH solution, indicating that the production of AMH-NCs using a combination of antisolvent precipitation and homogenization techniques could enhance the bioavailability of the drug.

Macrophage targeting with the novel carbopol-based miltefosine-loaded transfersomal gel for the treatment of cutaneous leishmaniasis: in vitro and in vivo analyses.

OBJECTIVE: The purpose of this study was to develop novel carbopol-based miltefosine-loaded transfersomal gel (HePCTG) for the treatment of cutaneous leishmaniasis (CL) via efficient targeting of leishmania infected macrophages. METHODS: Miltefosine-loaded transfersomes (HePCT) were prepared by ethanol injection method followed by their incorporation into carbopol gel to form HePCTG. The prepared HePCT were assessed for physicochemical properties including mean particle size, polydispersity index, zeta potential, entrapment efficiency, morphology, and deformability. Similarly, HePCTG was evaluated for physiochemical and rheological attributes. The in vitro release, skin permeation, skin irritation, anti-leishmanial activity, and in vivo efficacy in BALB/c mice against infected macrophages were also performed for HePCT. RESULTS: The optimized HePCT displayed a particle size of 168 nm with entrapment efficiency of 92%. HePCTG showed suitable viscosity, pH, and sustained release of the incorporated drug. Furthermore, HePCT and HePCTG demonstrated higher skin permeation than drug solution. The results of macrophage uptake study indicated improved drug intake by passive diffusion. The lower half maximal inhibitory concentration value, selectivity index and higher 50% cytotoxic concentration  value of HePCT compared to that of HePC solution demonstrated the improved anti-leishmanial efficacy and non-toxicity of the formulation. This was further confirmed by the notable reduction in parasite load and lesion size observed in in vivo anti-leishmanial study. CONCLUSION: It can be stated that the formulated HePCTG can effectively be used for the treatment of CL.

Rifampicin-loaded nanotransferosomal gel for treatment of cutaneous leishmaniasis: passive targeting via topical route.

Aim: In this study, the targeting of rifampicin (RIF)-loaded nanotransfersomes (NTs) incorporated in chitosan gel for leishmania-infected macrophages via the topical route was investigated. Materials & methods: NTs were prepared through a thin-film hydration process and incorporated into chitosan gel. Results: The mean particle size of the NTs was 190 nm, with 83% encapsulation efficiency. The permeation rate of the NTs was threefold higher than that of the RIF solution. The NTs improved cellular internalization via passive targeting, which was confirmed by macrophage uptake evaluation. A low IC50 value, flow cytometry analysis and in vivo study demonstrated the RIF-loaded NTs enhanced apoptosis and had better antileishmanial effects. Conclusion: RIF-loaded NT gel could be a fitting carrier for the delivery of antileishmanial drugs in cutaneous leishmaniasis.