Fig. 4: Photoswitching of a thermoresponsive hydrogel.

a Rheological data demonstrating the change in storage modulus G’ of a P1 hydrogel (5 wt% in deionized water) as a function of time at 37 °C under alternating green and blue light irradiation; b Rheological data of P1 hydrogel under green light irradiation followed by spontaneous thermal recovery.