Light-Curable Methacrylated Konjac Glucomannan Microspheres for Subcutaneous Tissue Filling

Skin soft tissue injury represents a prevalent dermatological condition often associated with postsurgical complications such as tissue defects and depressions. In this study, we developed methacrylated konjac glucomannan (KGMMA) through the modification of konjac glucomannan (KGM) with methyl acrylate (MA). The resulting KGMMA was subsequently emulsified and photo-cross-linked to form microspheres for soft tissue augmentation. Optimal preparation conditions were achieved with a 1:3 ratio of liquid paraffin/corn oil in the oil phase and a stirring speed of 800 rpm, yielding KGMMA microspheres with uniform sizes ranging from 100 to 200 μm. These microspheres demonstrated exceptional biocompatibility and showed potential in promoting NIH-3T3 cell proliferation. In vitro experiments revealed that KGMMA microspheres exhibited significant immunostimulatory activity and effectively suppressed TNF-α expression in the M1-type RAW264.7 cells. In vivo studies demonstrated that the microspheres elicited a controlled immune response during the initial phase of subcutaneous implantation and maintained structural integrity without significant degradation over 28 days, suggesting their suitability as a long-term soft tissue filler. These findings collectively indicate that injectable photo-cross-linked KGMMA microspheres possess substantial potential as an effective biomaterial for soft tissue defect restoration.