Thermotropic liquid crystals for precision drug delivery and diagnostics: Molecular design, characterization, and clinical translation

Thermoresponsive drug delivery systems offer precise, on-demand, and site-specific release of therapeutic agents in response to temperature changes, thereby enhancing drug stability, minimizing side effects, and improving patient compliance. Among these, thermotropic liquid crystals (TLCs) represent a unique class of temperature-dependent mesophases with tunable properties, extended-release profiles, and targeted delivery capabilities. This review provides an in-depth examination of thermoresponsive mesophases, with a particular focus on TLCs, exploring their fundamental chemistry, structural characteristics, and adaptability in pharmaceutical sciences. A comprehensive literature survey was conducted using Scopus, PubMed, and Web of Science to analyze recent advancements in TLC-based drug delivery, biomedical applications, and associated challenges. The review discusses the mechanisms by which TLC mesophases enable thermoresponsive and sustained drug administration, as well as their integration into biosensors and diagnostic platforms, highlighting their broader biomedical potential. Key formulation strategies are outlined, alongside major obstacles such as toxicity, formulation complexity, stability, scalability, and regulatory considerations that must be addressed for clinical translation. The article also showcases recent developments and future directions in this rapidly evolving field, emphasizing the need for biocompatible and scalable TLC systems. By addressing a significant gap in the application of thermotropic mesophases specifically for drug delivery, this review underscores the promise of TLCs as intelligent drug carriers and multifunctional biomedical materials, while also identifying critical areas for future research and development.