Green Light-Responsive CO-Releasing Polymeric Materials Derived from Ring-Opening Metathesis Polymerization.

Carbon monoxide (CO) is an important biological gasotransmitter in living cells. Precise spatial and temporal control over release of CO is a major requirement for clinical application. To date, the most reported carbon monoxide releasing materials use expensive fabrication methods and require harmful and poorly designed tissue-penetrating UV irradiation to initiate the CO release precisely at infected sites. Herein, we report the first example of utilizing a green light-responsive CO-releasing polymer synthesized via ring-opening metathesis polymerization. Both monomer and polymer were very stable under dark conditions and CO release was effectively triggered using minimal power and low energy wavelength irradiation (550 nm, ≤28 mW). Time-dependent density functional theory (TD-DFT) calculations were carried out to simulate the electronic transition and insight into the nature of the excitations for both and . TD-DFT calculations indicate that the absorption peak of is mainly due to the excitation of the seventh singlet excited state, S7. Furthermore, stretchable materials using polytetrafluoroethylene (PTFE) strips based on were fabricated to afford P-PTFE, which can be used as a simple, inexpensive, and portable CO storage bandage. Insignificant cytotoxicity as well as cell permeability was found for and against human embryonic kidney cells.