Fig. 1

Physicochemical characterization of Gel-N-ICG-NPs, loading efficiency, loading content, and release curve of NSC. a Representative TEM images of Gel-N-ICG-NPs. b Mean diameter size of bare Gel-NPs and Gel-N-ICG-NPs (n = 3, mean ± SD). c Zeta potential of Gel-NPs and Gel-N-ICG-NPs (n = 3, mean ± SD). d Stability studies of Gel-N-ICG-NPs under different pH values from 2 to 10 in PBS buffer and DMEM containing 10% FBS, respectively. e UV–vis–NIR spectra of Gel-N-ICG and free ICG which indicated the drug loading. f DLE and DLC of NSC in Gel-N-ICG-NPs. g Time course of drug release from Gel-N-ICG-NPs in different concentrations of gelatinase