BMP-2@PNH-TA hydrogel with osteogenic and antibacterial properties for integrated photothermal therapy

Abstract

Progress toward developing next-generation biomaterials applied in complex bone defect is expected to effectively integrate osteogenic and anti-bacteria capability. However, current biomaterials often achieve the two functions separately. Inspired by photothermal effect, exogenous light-induced thermal variations can efficiently facilitate bone regeneration and bacteria eradication. Here, a bioactive hydrogel BMP-2@PNH-TA with simultaneously osteogenic and anti-bacterial capacities is presented, which is based on the near infrared (NIR) induced photothermal effect to perform integrated photothermal therapy (PTT). In detail, photothermal effect and photothermal-controlled release of osteogenic and anti-bacterial factors through sponge-like effect could exert integrated influence on bone regeneration under complex situation. The composite hydrogel can mediate pro-osteogenesis under mild temperature and controlled release of BMP-2 and tannin in response to NIR stimulation with low power, while efficiently eradicate bacteria via controlled release of O-HACC and thermal effect with high power. The customized PTT strategy significantly shortened the duration time of bone regeneration up to almost 50% in rat cranial bone defect. It is anticipated that the concept of integrated PTT for bone regeneration will cast new insights into developing high-performance therapeutic strategy with combined biological functions.