Figure 2.
(a) pH sensitive croconaine rotaxane (CrocRot). (b) UV/Vis absorption of CrocRot-SL at various pH values, [CrocRot] = 3 μM. (c) UV/Vis absorption plots of CrocRot-SL in buffer at pH 5.0, acquired initially (solid line) and after standing for 24 hour (dashed line) at 4°C. (c) Temperature changes during laser irradiation (808 nm, 3.5 W/cm2) of CrocRot-SL samples at different pH values. (d) Multiple heating cycles of CrocRot-SL at pH 5.0 due to periodic laser irradiation (808 nm).