Two-dimensional black phosphorus (BP) are featured with excellent near-infrared (NIR) photothermal and photodynamic effects, biocompatibility and biodegradability. They have captured extensive attention in biomedical applications, such as optical therapies, drug/gene delivery, bioimaging, and sensing. 

NIR light-controlled biomineralization has immense clinical potential especially in tissue engineering.

A research group led by Prof. YU Xuefeng from Shenzhen Institutes of Advanced Technology (SIAT) of the Chinese Academy of Sciences, in cooperation with Prof. SHAO Jundong from Shenzhen University (SZU), demonstrated photochemical activity of BP in the NIR light-controlled in situ biomineralization of BP incorporated hydrogel. 

In the study, the photochemical activity of BP sheets, which were reported by this group previously, arising from the formation of PO₄^3- during NIR light-controlled in situ biomineralization was systematically investigated and demonstrated.

Owing to the excellent NIR absorption, BP sheets under NIR illumination exhibited much faster degradation both in moist air and solution. The chemical activity of BP sheets was enhanced by NIR light irradiation. 

The BP sheets could not only provide a phosphorus source and nucleation sites, but also accelerate the reaction between PO₄^3- and Ca²⁺ to promote biomineralization. 

The researchers applied BP sheets with excellent photochemical activity to controlled biomineralization of hydrogels in situ, and tailored the mechanical properties and biomineralization ability by modulating the irradiation time and location of the NIR light.

The study was published in Advanced Science.