Using Nuclear Magnetic Resonance Spectroscopy to Probe Hydrogels Formed by Sodium Deoxycholate

Self-Healing Hydrogel Resulting from the Noncovalent Interaction between Ropivacaine and Low-Molecular-Weight Gelator Sodium Deoxycholate Achieves Stable and Endurable Local Analgesia in Vivo

Regional analgesia based on the local anesthetic ropivacaine plays a crucial role in postoperative pain management and recovery; however, the short duration of analgesia limits its clinical potential. Various drug delivery systems such as microparticles and lipid carriers have been used to prolong the analgesic effect, yet most of them are prone to abrupt release from the site of administration or have poor analgesic effects of less than 48 h, which fail to meet the needs of postoperative analgesia. In this study, a low-molecular-weight gelator sodium deoxycholate-based hydrogel loaded with ropivacaine (DC-ROP gel) was designed for long-acting analgesia. The noncovalent interaction between ropivacaine and sodium deoxycholate helps to improve the stability and sustained release performance of the gel. This internal drug-binding hydrogel also avoids experiencing the burst release effect commonly seen in polymer hydrogels previously reported for the slow release of local anesthetics. DC-ROP gel exhibited the dual advantages of self-healing after compression and long-term controlled release. In mice with inflammatory pain, DC-ROP gel achieved peripheral nerve block for more than 1 week after a single injection. Histological and blood biochemical analyses confirmed that the DC-ROP gel did not produce systemic toxicity, and cytotoxicity experiments demonstrated that the DC-ROP gel resulted in low irritation. These results suggest that DC-ROP gel provides a promising strategy for local anesthetics in long-term postoperative pain management, broadening the potential of bile salt-based low-molecular-weight hydrogels for drug delivery.

Solubilization and Photostabilization in a Sodium Deoxycholate Hydrogel of a Neutral Conjugated Thiophene Oligomer and Polymer

Oligo(3-hexylthiophene-co-1,4-phenylene) and poly(3-hexylthiophene) were solubilized in sodium deoxycholate self-assemblies in water solutions and hydrogels, with the goal of solubilizing sufficient material in a hydrogel for fluorescence applications. The neutral conjugated oligomer and polymer were incorporated as monomers into the self-assemblies with sodium deoxycholate aggregates, leading to the photoprotection of these neutral conjugated and water-insoluble molecules. Dynamic light scattering, rheology, and fluorescence experiments established that the deoxycholate aggregation and gel formation properties were not altered with the incorporation of the oligomer or polymer into the deoxycholate self-assemblies, showing that this adaptable host system with some molecular recognition elements is a viable strategy to incorporate into hydrogels neutral conjugated molecules as isolated monomers. This strategy has the potential to be used when conjugated molecules are used for fluorescence applications in hydrogels.

Exploring the Potential of Artificial Intelligence for Hydrogel Development-A Short Review

AI and ML have emerged as transformative tools in various scientific domains, including hydrogel design. This work explores the integration of AI and ML techniques in the realm of hydrogel development, highlighting their significance in enhancing the design, characterisation, and optimisation of hydrogels for diverse applications. We introduced the concept of AI train hydrogel design, underscoring its potential to decode intricate relationships between hydrogel compositions, structures, and properties from complex data sets. In this work, we outlined classical physical and chemical techniques in hydrogel design, setting the stage for AI/ML advancements. These methods provide a foundational understanding for the subsequent AI-driven innovations. Numerical and analytical methods empowered by AI/ML were also included. These computational tools enable predictive simulations of hydrogel behaviour under varying conditions, aiding in property customisation. We also emphasised AI's impact, elucidating its role in rapid material discovery, precise property predictions, and optimal design. ML techniques like neural networks and support vector machines that expedite pattern recognition and predictive modelling using vast datasets, advancing hydrogel formulation discovery are also presented. AI and ML's have a transformative influence on hydrogel design. AI and ML have revolutionised hydrogel design by expediting material discovery, optimising properties, reducing costs, and enabling precise customisation. These technologies have the potential to address pressing healthcare and biomedical challenges, offering innovative solutions for drug delivery, tissue engineering, wound healing, and more. By harmonising computational insights with classical techniques, researchers can unlock unprecedented hydrogel potentials, tailoring solutions for diverse applications.

Impact of molecular interactions between hydrophilic phytosterol glycosyl derivatives and bile salts on the micellar solubility of cholesterol

Hydrophilic phytosterol glycosyl derivatives are synthetic phytosterol analogues by coupling with the glycosyl moiety to improve the water solubility and bioaccessibility of free phytosterols. The aim of this study is to clarify the molecular interaction of phytosterol glycosyl derivatives with bile salts and the consequent impact on cholesterol solubilization. Sharp nonlinear decrease in the micellar solubility of cholesterol and accompanying changes in particle size, zeta potential and microtopography of mixed micelles were observed when phytosterol glycosyl derivatives were introduced in cholesterol-loaded bile salt micelles. These results suggested that β-sitosterol glycosyl derivatives molecules indeed participated in the formation of mixed micelles. Further, nuclear magnetic resonance showed that the structural change of mixed micelles was caused by the insertion of β-sitosterol glycosyl derivatives via hydrogen bonds with sodium taurocholate, which resulted in the low cholesterol solubilization. Moreover, the hydrogen-bond interactions were apparently influenced by the glycosyl moiety of β-sitosterol glycosyl derivatives. These molecular mechanisms may contribute to the development of cholesterol-absorption inhibitors.