Copolymer Composition and Nanoparticle Configuration Enhance in vitro Drug Release Behavior of Poorly Water-soluble Progesterone for Oral Formulations

Advances in progesterone delivery systems: Still work in progress?

Progesterone is a natural steroidal sex hormone in the human body, mainly secreted through the adrenal cortex, ovary, and placenta. In humans, progesterone is essential for endometrium transformation in the uterus at the time of ovulation and maintenance of pregnancy. When the body cannot produce enough progesterone for specific ailments, it is administered via different routes such as oral, vaginal, transdermal, topical, parental, and intranasal routes. Although progesterone is commercially available in multiple conventional formulations, low solubility, less permeability and extensive hepatic first-pass metabolism are the major constraints to its delivery. These challenges can be overcome substantially by formulating progesterone into novel delivery systems like lipid carriers, polymeric carriers, hydrogels, several nanocarriers, depot and controlled release systems. Various research papers and patents have been published in the last two decades on progesterone delivery systems; clinical studies were conducted to establish safety and efficacy. This review is focused on the pharmacodynamic and pharmacokinetic parameters of progesterone, its delivery constraints, and various advanced delivery systems of progesterone.

Development of intranasal implantable devices for schizophrenia treatment

In this work the preparation and characterisation of intranasal implants for the delivery of risperidone (RIS) is described. The aim of this work is to develop better therapies to treat chronic conditions affecting the brain such as schizophrenia. This type of systems combines the advantages of intranasal drug delivery with sustained drug release. The resulting implants were prepared using biodegradable materials, including poly(caprolactone) (PCL) and poly(lactic-co-glycolic acid) (PLGA). These polymers were combined with water-soluble compounds, such as poly(ethylene glycol) (PEG) 600, PEG 3000, and Tween® 80 using a solvent-casting method. The resulting implants contained RIS loadings ranging between 25 and 50%. The obtained implants were characterised using a range of techniques including thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), attenuated total reflectance-Fourier transform infrared (ATR-FTIR), X-ray diffraction (XRD), and Scanning Electron Microscopy (SEM). Moreover, in vitro RIS release was evaluated showing that the addition of water-soluble compounds exhibited significant faster release profiles compared to pristine PCL and PLGA-based implants. Interestingly, PCL-based implants containing 25% of RIS and PLGA-based implants loaded with 50% of RIS showed sustained drug release profiles up to 90 days. The former showed faster release rates over the first 28 days but after this period PLGA implants presented higher release rates. The permeability of RIS released from the implants through a model membrane simulating nasal mucosa was subsequently evaluated showing desirable permeation rate of around 2 mg/day. Finally, following in vitro biocompatibility studies, PCL and PLGA-based implants showed acceptable biocompatibility. These results suggested that the resulting implants displayed potential of providing prolonged drug release for brain-targeting drugs.

A Novel Sustained Anti-Inflammatory Effect of Atorvastatin-Calcium PLGA Nanoparticles: In Vitro Optimization and In Vivo Evaluation

Atorvastatin Calcium (At-Ca) has pleiotropic effect as anti-inflammatory drug beside its main antihyperlipidemic action. Our study was conducted to modulate the anti-inflammatory effect of At-Ca to be efficiently sustained for longer time. Single oil-water emulsion solvent evaporation technique was used to fabricate At-Ca into polymeric nanoparticles (NPs). In vitro optimization survey was performed on Poly(lactide-co-glycolide) (PLGA) loaded with At-Ca regrading to particle size, polydispersity index (PDI), zeta potential, percent entrapment efficiency (% EE), surface morphology and in vitro release pattern. In vitro drug-polymers interactions were fully scanned using Fourier-Transform Infrared Spectroscopy (FTIR) and Differential Scanning calorimetry (DSC) proving that the method of fabrication is an optimal strategy maintaining the drug structure with no interaction with polymeric matrix. The optimized formula with particle size (248.2 ± 15.13 nm), PDI (0.126 ± 0.048), zeta potential (-12.41 ± 4.80 mV), % EE (87.63 ± 3.21%), initial burst (39.78 ± 6.74%) and percent cumulative release (83.63 ± 3.71%) was orally administered in Male Sprague-Dawley rats to study the sustained anti-inflammatory effect of At-Ca PLGA NPs after carrageenan induced inflammation. In vivo results demonstrate that AT-Ca NPs has a sustained effect extending for approximately three days. Additionally, the histological examination revealed that the epidermal/dermal layers restore their typical normal cellular alignment with healthy architecture.

Drug-zein@lipid hybrid nanoparticles: Electrospraying preparation and drug extended release application

The reasonable selection and elaborate conversion of raw materials into desired functional products represent a main topic in modern material engineering. In this study, zein (a plant protein) and lipids (extracted from egg yolk) are converted into a new type of drug-polymer@lipid hybrid nanoparticles (HNPs) via modified coaxial electrospraying. Tamoxifen citrate (TC) is used as a model anticancer drug to prepare TC-zein monolithic nanocomposites (MNCs) via traditional blended electrospraying; these MNCs are then used for comparison. Modified coaxial electrospraying is a continuous and robust process for the preparation of solid particles because of the action of unsolidifiable shell lipid solutions. HNPs have a round morphology with clear core-shell nanostructures, whereas MNCs have an indented flat morphology. Although both hold the drug in an amorphous state because of the fine compatibility of TC and zein, HNPs demonstrate a better sustained release of TC compared with MNCs in terms of retarding initial burst release (6.7 %±2.9 % vs. 37.2 %±4.3 %) and prolonged linear release period (20.47 h vs. 4.97 h for releasing 90 % of the loaded drug). Mechanisms by which the shell's lipid layer adjusts the release behavior of TC molecules are proposed. The present protocol based on coaxial electrospraying shows a new strategy of combining edible protein and lipids to fabricate advanced functional nanomaterials.

Physicochemical Characterization of Finasteride Nanosystem for Enhanced Topical Delivery

INTRODUCTION

The current work aimed to formulate a novel chitosan-based finasteride nanosystem (FNS-NS) for skin delivery to optimize the drug availability in skin for a longer time and enhance ex vivo performance of finasteride against androgenic alopecia.

METHODS

Both undecorated and chitosan decorated FNS-NSs were synthesized by a high energy emulsification technique. All the prepared nanosystems were further subjected to physicochemical characterizations like pH, viscosity, encapsulation efficiency, surface morphology and in vitro drug release behavior. The influence of the nanosystem on the drug permeation and retention in rat skin was examined using Franz diffusion cell apparatus.

RESULTS

The droplet size of developed nanosystems ranged from 41 to 864 nm with a low polydispersity index. The zeta potential of the nanosystems was between -10 mV and +56 mV. This chitosan decorated nanosystem exhibited controlled drug release, ie about 78-97% in 24 h. Among all the nanosystems, our chitosan decorated formulation (F5) had low drug permeation (16.35 µg/cm2) and higher drug retention (10.81 µg/cm2).

CONCLUSION

The abovementioned results demonstrate satisfactory in vitro drug release, skin retention profiles and ex vivo performance with chitosan decorated FNS-NS (F5). This optimized formulation could increase drug availability in skin and could become a promising carrier for topical delivery to treat androgenic alopecia.