Antibacterial conductive polyacrylamide/quaternary ammonium chitosan hydrogel for electromagnetic interference shielding and strain sensing.

The utilization of biomass-based conductive polymer hydrogels in wearable electronics holds great promise for advancing performance and sustainability. An interpenetrating network of polyacrylamide/2-hydroxypropyltrimethyl ammonium chloride chitosan (PAM/HACC) was firstly obtained through thermal-initiation polymerization of AM monomers in the presence of HACC. The positively charged groups on HACC provide strong electrostatic interactions and hydrogen bonding with the PAM polymer chains, leading to improved mechanical strength and stability of the hydrogel network. Subsequently, the PAM/HACC networks served as the skeletons for the in-situ polymerization of polypyrrole (PPy), and then the resulting conductive hydrogel demonstrated stable electromagnetic shielding performance (40 dB), high sensitivity for strain sensing (gauge factor = 2.56). Moreover, the incorporation of quaternary ammonium chitosan into PAM hydrogels enhances their antimicrobial activity, making them more suitable for applications in bacterial contamination or low-temperature environments. This conductive hydrogel, with its versatility and excellent mechanical properties, shows great potential in applications such as electronic skin and flexible/wearable electronics.

Soluplus-Mediated Diosgenin Amorphous Solid Dispersion with High Solubility and High Stability: Development, Characterization and Oral Bioavailability.

BACKGROUND AND PURPOSE: The traditional Chinese medicine, diosgenin (Dio), has attracted increasing attention because it possesses various therapeutic effects, including anti-tumor, anti-infective and anti-allergic properties. However, the commercial application of Dio is limited by its extremely low aqueous solubility and inferior bioavailability in vivo. Soluplus, a novel excipient, has great solubilization and capacity of crystallization inhibition. The purpose of this study was to prepare Soluplus-mediated Dio amorphous solid dispersions (ASDs) to improve its solubility, bioavailability and stability. METHODS: The crystallization inhibition studies were firstly carried out to select excipients using a solvent shift method. According to solubility and dissolution results, the preparation methods and the ratios of drug to excipient were further optimized. The interaction between Dio and Soluplus was characterized by differential scanning calorimetry (DSC), fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM), powder X-ray diffraction (PXRD) and molecular docking. The pharmacokinetic study was conducted to explore the potential of Dio ASDs for oral administration. Furthermore, the long-term stability of Dio ASDs was also investigated. RESULTS: Soluplus was preliminarily selected from various excipients because of its potential to improve solubility and stability. The optimized ASDs significantly improved the aqueous solubility of Dio due to its amorphization and the molecular interactions between Dio and Soluplus, as evidenced by dissolution test in vitro, DSC, FT-IR spectroscopy, SEM, PXRD and molecular docking technique. Furthermore, pharmacokinetic studies in rats revealed that the bioavailability of Dio from ASDs was improved about 5 times. In addition, Dio ASDs were stable when stored at 40°C and 75% humidity for 6 months. CONCLUSION: These results indicated that Dio ASDs, with its high solubility, high bioavailability and high stability, would open a promising way in pharmaceutical applications.

Toltrazuril mixed nanomicelle delivery system based on sodium deoxycholate-Brij C20 polyethylene ether-triton x100: Characterization, solubility, and bioavailability study.

Toltrazuril (Tol) is a broad-spectrum anticoccidiosis drug that is widely used in the prevention and treatment of coccidiosis infection in poultry and mammals. However, the drug has poor aqueous solubility (25 °C, 0.41 µg/mL), and its dose escalation for systemic administration remains challenging. We engineered a Tol mixed nanomicelle (TMNM) delivery system based on sodium deoxycholate-Brij C20 polyethylene ether-triton x100 (NaDC-Brij58-Tx100) as surfactants by film hydration method. The physical properties of TMNM were characterized, and the pharmacokinetic parameters of Tol and TMNM were compared. The average particle size, drug loading, saturated solubility, and critical micelle concentration (CMC) of the TMNM system were 12.28 ±â€¯0.48 nm, 3.38 ±â€¯0.12%, 3921.70 ±â€¯0.01 µg/mL (8170-fold compared with Tol), and 0.0172 mg/mL, respectively. Transmission electron microscopy (TEM), scanning electron microscopy (SEM) micrographs, differential scanning calorimetry (DSC) and X-ray diffraction (XRD) were performed, and the results showed TMNM formation. Furthermore, the TMNM had greater bioavailability (215%) than the Tol solution. The significant increase in the drug solubility and bioavailability of TMNM suggested the TMNM is a potential oral and parenteral delivery system for Tol and has wide application prospects in the clinical context.