NIR-excited nanosystem for photodynamic therapy of port-wine stain

Port-wine Stain(PWS) is a benign congenital capillary malformation. In recent years, hemporfin (HMME)-mediated vasoactive photodynamic therapy (HMME-PDT) emerged as a new alterative treatment for PWS. Unfortunately, the therapeutic depth of visible light-excited HMME-PDT is not satisfactory. The upconversion material(UCNP) emits UV/visible light under near-infrared excitation(NIR) and can bind to photosensitizers. The combination of the two not only plays the role of PDT, but also increases the depth of penetration. We synthesized NaYF4: 30% Yb, 2% Er@NaYF4, and imparted hydrophilicity by binding to DSPE-PEG 2000. Then the HMME was successfully mounted. Pig skins of different thicknesses were used to detect the ROS yield of UCNP@HMME. UCNP emits green light at 532nm when excited by NIR. UCNP can be successfully loaded on HMME. UCNP@HMME is still stable PDT at a depth of 8 mm. We developed an NIR photoactivated nanosystem. This may provide a new treatment modality for hypertrophic PWS.