Fig. 4. (a) Preparation of A1094 J-aggregate nanomicelles through self-assembly. (b) PA intensity of the A1094 J-aggregates and the A1094 monomer phantoms at different wavelengths. (c) PA images of mouse brain glioma at different time points in vivo at 1200 nm. Adapted from ref. 58. Copyright© 2019 American Chemical Society. (d) Redox-interconvertible hexaphyrins containing doubly N-fused congeners with different molecular symmetries can serve as functional and tunable NIR-II PA dyes. Adapted from ref. 59. Copyright© 2020 American Chemical Society. (e) Depiction for the preparation of NiPNP. (f) PA/US overlaid images of the tube filled with NiPNP at different depths prepared with chicken breast tissues. Adapted from ref. 60. Copyright© 2020 Royal Society of Chemistry. (g) Synthetic route and schematic diagram of BDP-FeNPs. (h) PA images of BDP-FeNPs injected mice at a different time under 1100 nm laser irradiation; the tumor region is encircled. Adapted from ref. 61. Copyright© 2020 Royal Society of Chemistry.