MXene-Based Photothermal-Responsive Injectable Hydrogel Microsphere Modulates Physicochemical Microenvironment to Alleviate Osteoarthritis.

Osteoarthritis (OA) is a physical lubrication microenvironment-inadequate disease accompanied by a sustained chronic chemical inflammation microenvironment and the progression of articular cartilage destruction. Despite the promising OA treatment outcomes observed in the enhancement of lubrication inspired by ball bearings to reduce friction and support loads, the therapeutic effect of near-infrared (NIR) irradiation-based photothermal-responsive controlled release "smart hydrogel microspheres" on OA remains unclear. Here, we prepared MXene/NIPIAM-based photothermal-responsive injectable hydrogel microspheres encapsulating diclofenac sodium using a microfluidic system. Consequently, NIR irradiation-based photothermal-responsive controlled release "smart hydrogel microspheres" demonstrate beneficial therapeutic effects in the treatment of OA by modulating the physical lubrication and chemical chronic inflammation microenvironment, laying the foundation for the application of smart hydrogel microsphere delivery systems loaded with bioactive factors (including agents, cells, and factors) to regulate multiple pathological microenvironments in regenerative medicine.