The first-pass effect and low water solubility are crucial limitations that hinder the drug from being absorbed into the systemic circulation, followed by oral administration. The mucoadhesive buccal delivery system offers direct drug absorption through the mucosa, reaching systemic circulation and bypassing the hepatic first-pass metabolism. This approach ensures high bioavailability and overcomes the swallowing difficulties associated with traditional oral delivery systems. Here, we developed mucoadhesive buccal films for oral delivery of poorly water-soluble drugs using hot-melt extrusion (HME). Poly(2-ethyl-2-oxazoline) (PEtOx), a potential pharmaceutical excipient with high biocompatibility and versatility, was used as the primary matrix for solubility enhancement. Fenofibrate (FB), a typical Biopharmaceutics Classification System (BCS) class II drug with virtually insolubility in water, was used as the model drug. Hydroxypropyl cellulose (HPC), hydroxypropyl methylcellulose (HPMC), and polyethylene oxide (PEO) were combined with PEtOx to adjust the mucoadhesive property. The prepared films were in vitro characterized to delineate the impact of key formulation factors on the mechanical properties, bioadhesion, and solubility enhancement effect. We demonstrated that the complexation of PEtOx with 20% PEO (F8) resulted in over 95% drug release within 2 h, representing an over 5-fold enhancement in solubility compared to the free drug. This F8 formulation exhibited significant bioadhesion among the other formulations, with a 2.2- to 2.7-fold increase in Peak Force (PAF) and work of adhesion (WAD) relative to the control group. This study investigates HME as a continuous fabrication process for developing PEtOx-based buccal film, demonstrating a potential bioadhesive drug delivery system with a solubility improvement effect.

Background/Objectives: This study aimed to develop a novel amorphous solid dispersion (ASD) platform using poly(2-ethyl-2-oxazoline) (PEtOx) for the solubility enhancement of poorly water-soluble drugs. Fenofibrate (FB), a Biopharmaceutics Classification System (BCS) Class II drug, was selected as the model drug. The novelty of this work lies in the formulation of dual-matrix systems by blending PEtOx of varying molecular weights (50 kDa, 200 kDa, 500 kDa) with solubility-enhancing polymers, Soluplus^® and Kollidon^® VA64, to investigate component compatibility, synergistic solubility enhancement, and the influence of PEtOx molecular weight on drug release. Methods: ASDs were prepared via hot-melt extrusion (HME) and characterized using differential scanning calorimetry (DSC), scanning electron microscopy (SEM), powder X-ray diffraction (PXRD), and Fourier transform–infrared spectroscopy (FTIR) to confirm FB amorphization and evaluate drug–polymer interactions. In vitro dissolution testing was performed to assess drug release performance, and stability studies were conducted at ambient conditions for one month to evaluate physical stability. Results: DSC, PXRD, and FTIR confirmed the successful amorphization of FB and good miscibility between PEtOx and the selected excipients. In vitro dissolution studies showed an 8–12-fold increase in FB release from ASDs compared to crystalline drug. Lower-molecular-weight PEtOx grades yielded faster release profiles, while binary blends with Soluplus^® or Kollidon^® VA64 enabled tailored drug release. Stability testing indicated that all formulations maintained their amorphous state over one month. Conclusions: PEtOx-based ASDs represent a versatile platform for enhancing the solubility and dissolution of poorly water-soluble drugs. By adjusting polymer molecular weight and combining with complementary excipients, release profiles can be optimized to achieve improved performance and stability.

Previously the development and implementation of a new mechanistic model for oil and gas production environments was described. This initial development was a single point model that predicted the CO2 corrosion rate for a given set of conditions. The model has subsequently been further developed to simulate the change in water chemistry and associated corrosion rate along the length of a flow line. As a volume of water moves along the flow line the water chemistry is modified as a result of the flux of iron ions from the corroding pipe wall surface. The associated change in pH from the addition of ferrous ions further influences the CO2 equilibrium. These two effects, varying pH and CO2 equilibrium, combined in-turn to affect the predicted corrosion rate. The model simulates the changing water chemistry and corrosion rate by repeatedly recalculating the mechanistic corrosion rate model for small increments of time. The water chemistry and corrosion rate profiles for prototypical flow line conditions are presented and discussed.