Fig. 5

Photothermally-driven spatiotemporally controlled drug delivery using A-PHN. a Schematic mechanisms of drug release from a dehydrated A-PHN by light illumination. b Cumulative dox release under light exposure by measuring the absorbance of free dox using different pH conditions. c Time-coursed Raman spectra with continuous light illumination. d Monitoring the Raman spectra of released dox under temporally controlled light modulation. (i) Schematics for the discrete light illuminating experiments. (ii) Switchable release profile of dox@A-PHN under laser on/off conditions. (iii) Cumulative dox signal kinetics under discrete light illumination (n = 6). e Observation of light-triggered dox delivery using A-PHN. (i) Fluorescent colocalization images of released dox within the nucleus. The red color indicates the dox, and the blue indicates the nucleus. The scale bar is 50 µm. (ii) Colocalization degree monitoring by Pearson’s coefficient with light exposure time (n = 3). f Cell viability test using MTT assay of A-PHN and dox@A-PHN with/without light exposure (n = 5)