Poloxamer-based injectable hydrogels as matrices for localized anti-inflammatory drug delivery in meniscus injuries

Abstract

Poloxamer-based hydrogels, composed of thermoreversible triblock copolymers, are promising drug delivery systems due to their ability to transition from a liquid to a gel state at physiological temperatures, enabling minimally invasive injection and localized, sustained release of therapeutic agents. In this study, poloxamer hydrogels were prepared with diclofenac sodium salt and paracetamol as model anti-inflammatory drugs, and characterized for morphology, osmolarity, pH, and temperature sensitivity. Drug loading optimization was performed to ensure homogeneous dispersion, and release kinetics were evaluated by spectrophotometric analysis, with mathematical modeling used to describe and predict drug release mechanisms from the hydrogel matrix. The optimized poloxamer gels exhibited an appropriate sol–gel transition near body temperature (26–37 °C), stable pH, and osmolarity suitable for biomedical use. Drug release profiles showed controlled, sustained release of both diclofenac sodium and paracetamol over extended periods, with mathematical modeling indicating that diffusion-based mechanisms predominated in drug release from the hydrogel matrix, validating the system design for targeted, localized therapy. These findings demonstrate that poloxamer-based injectable hydrogels effectively deliver anti-inflammatory agents with controlled release, representing a versatile platform for localized drug delivery in regenerative medicine and orthopedic applications, particularly for intra-articular treatment of musculoskeletal disorders, thereby supporting improved therapeutic outcomes while minimizing systemic exposure and associated side effects.