Fig. 2

a The bright field and fluorescence microscope images of the MN patches after in vivo application on the mouse skin, the scale bar represents 500 µm; b The visible absorption spectrum of PVPVA and IR820; c The calibration curve of IR820 by measuring the visible absorbance intensity at 700 nm; d The residual percentage of IR820 in the MN patch after in vivo application on the mouse skin; e The calibration curve of CDDP by measuring the atomic absorbance intensity at 265.9 nm; f The residual percentage of CDDP in the MN patch after in vivo application on the mouse skin