Conventional shape memory polymers (SMPs) are restricted to predetermined permanent shapes and therefore cannot be reconfigured arbitrarily to adapt to variant application scenarios. Meanwhile, shape memory behaviour is mostly thermally active and is often induced by direct heating and lacks spatial or remote control. Herein, we report a novel SMP with a reconfigurable network containing a semi-crystalline polymer chain, radically exchangeable covalent bond and photothermoresponsive carbolong complex moiety. The photothermal effect of the carbolong complex and the thermal responsiveness of the semi-crystalline polymer chain and radically exchangeable covalent bond lead to shape memory behaviour and network topological rearrangement using near-infrared light irradiation. Such a strategy offers an opportunity for building reconfigurable shape memory polymers that can be manipulated by either direct heating or remote light irradiation.
Photo-generation of a proton gradient over a lipid bilayer is of interest due to its essential role in photosynthetic bacteria. Membrane asymmetry is key to the proton gradient generation via directional proton transport. Here, we report a light-driven proton pump based on two-dimensional, porphyrin-based Janus metal-organic layers (Janus-MOLs). The Janus-MOL, functionalized with carboxyquinone on one side and Acitretin on the other via a microemulsion-based method, was attached to liposome surface. Upon photoexcitation, the porphyrins initiate electron and hole transfers to carboxyquinone and Acitretin, respectively, which undergo redox reactions with freely diffusing quinone (Q)/hydrosemiquinone (HQ·) in the lipid bilayer to produce a concentration gradient of quinone-based species. Owing to different pKa values of HQ+and HQ·, these redox reactions trigger proton transport across the membrane to create a pH gradient, which drives ATP production by CFoF1-ATP synthase in a similar fashion as photosynthetic bacteria.