Investigation of Drug–Polymer Miscibility and Solubilization on Meloxicam Binary Solid Dispersion

Thermosensitive Polyurethane-Based Hydrogels as Potential Vehicles for Meloxicam Delivery

Meloxicam (MX) is a nonsteroidal anti-inflammatory drug (NSAID) used mainly to reduce pain, inflammation, and fever. In the present study, thermosensitive polyurethane (PU)-based hydrogels with various excipients (PEG, PVP, HPC, and essential oil) were prepared and loaded with MX. Rheological investigations were carried out on the PU-based formulations in various shear regimes, and their viscoelastic characteristics were determined. The average size of the PU micelles was 35.8 nm at 37 °C and slightly increased at 37 nm in the presence of MX. The zeta potential values of the hydrogels were between -10 mV and -11.5 mV. At pH = 6 and temperature of 37 °C, the formulated PU-based hydrogels loaded with MX could deliver significant amounts of the active substance, between 60% and 80% over 24-48 h and more than 90% within 2 weeks. It was found that anomalous transport phenomena dominated MX's release mechanism from the PU-based networks. The results are encouraging for further studies aiming to design alternative carriers to commercial dosage forms of nonsteroidal anti-inflammatory drugs.

A systematic and robust assessment of hot-melt extrusion-based amorphous solid dispersions: Theoretical prediction to practical implementation

Amorphous solid dispersions (ASDs) have gained attention as a formulation strategy in recent years, with the potential to improve the apparent solubility and, hence, the oral bioavailability of poorly soluble drugs. The process of formulating ASDs is commonly faced with challenges owing to the intrinsic physical and chemical instability of the initial amorphous form and the long-term physical stability of drug formulations. Numerous research publications on hot-melt extrusion (HME) technology have demonstrated that it is the most efficient approach for manufacturing reasonably stable ASDs. The HME technique has been established as a faster scale-up production strategy for formulation evaluation and has the potential to minimize the time to market. Thermodynamic evaluation and theoretical predictions of drug-polymer solubility and miscibility may assist to reduce the product development cost by HME. This review article highlights robust and established prediction theories and experimental approaches for the selection of polymeric carriers for the development of hot melt extrusion based stable amorphous solid dispersions (ASDs). In addition, this review makes a significant contribution to the literature as a pilot guide for ASD assessment, as well as to confirm the drug-polymer compatibility and physical stability of HME-based formulations.

Overview of nanoparticulate strategies for solubility enhancement of poorly soluble drugs

Poor aqueous solubility and poor bioavailability are major issues with many pharmaceutical industries. By some estimation, 70-90% drug candidates in development stage while up-to 40% of the marketed products are poorly soluble which leads to low bioavailability, reduced therapeutic effects and dosage escalation. That's why solubility is an important factor to consider during design and manufacturing of the pharmaceutical products. To-date, various strategies have been explored to tackle the issue of poor solubility. This review article focuses the updated overview of commonly used macro and nano drug delivery systems and techniques such as micronization, solid dispersion (SD), supercritical fluid (SCF), hydrotropy, co-solvency, micellar solubilization, cryogenic technique, inclusion complex formation-based techniques, nanosuspension, solid lipid nanoparticles, and nanogels/nanomatrices explored for solubility enhancement of poorly soluble drugs. Among various techniques, nanomatrices were found a promising and impeccable strategy for solubility enhancement of poorly soluble drugs. This article also describes the mechanism of action of each technique used in solubilization enhancement.

Controlled release of enrofloxacin by vanillin-crosslinked chitosan-polyvinyl alcohol blends

In transdermal drug delivery applications uniform drug distribution and sustained release are of great importance to decrease the side effects. In this direction in the present research, vanillin crosslinked chitosan (CS) and polyvinyl alcohol (PVA) blend based matrix-type transdermal system was prepared by casting and drying of aqueous solutions for local delivery of enrofloxacin (ENR) drug. Subsequently, the properties including the morphology, chemical structure, thermal behavior, tensile strength, crosslinking degree, weight uniformity, thickness, swelling and drug release of the CS-PVA blend films before and after crosslinking were characterized. In vitro drug release profiles showed the sustained release of ENR by the incorporation of vanillin as a crosslinker into the CS-PVA polymer matrix. Furthermore, the release kinetic profiles revealed that the followed mechanism for all samples was Higuchi and the increase of vanillin concentration in the blend films resulted in the change of diffusion mechanism from anomalous transport to Fickian diffusion. Overall, the obtained results suggest that the investigated vanillin crosslinked CS-PVA matrix-type films are potential candidates for transdermal drug delivery system.