A disulfide bond is a covalent link between two sulfur atoms, formed by the oxidation of two thiol groups. The bond is strong under normal conditions but is cleaved by a reducing agent, which makes it a reversible crosslink in a redox-responsive material [1]. The exchange with a free thiol is fast at a pH above the acidity constant of the thiol, so the rate can be tuned by the local environment [2]. In a polymer network the disulfide provides a mechanism for stress relaxation and for self-repair, because the bond can break and re-form under load [3]. The reduction potential of the couple sets the conditions under which the link survives, and the glutathione concentration inside a cell is enough to cleave it [4]. The dynamic character also means that a disulfide-crosslinked gel creeps under a sustained load [5].
- thiol oxidation
- reversible crosslink
- redox responsive
- thiol-disulfide exchange
- glutathione
- self-repair
- stress relaxation
References
- Liu, L.; Liu, P.; Synthesis strategies for disulfide bond-containing polymer-based drug delivery system for reduction-responsive controlled release. Frontiers of Materials Science 2015, 9, 211-226, 10.1007/s11706-015-0283-y.
- Pei, Q.; Han, Q.; Tang, F.; Wu, J.; Xu, S.; Zhang, M.; Ding, A.; Gallic‐Acid‐Modified Naphthalimide Containing Disulfide Bond as Reduction‐Responsive Supramolecular Organogelator. ChemistrySelect 2022, 7, e202201296, 10.1002/slct.202201296.
- Remtulla, R.; Das, S.K.; Levin, L.A.; In Silico Modeling of Myelin Oligodendrocyte Glycoprotein Disulfide Bond Reduction by Phosphine-Borane Complexes. Pharmaceuticals 2024, 17, 1417, 10.3390/ph17111417.
- Hayashida, O.; Imamura, S.; Miyazaki, T.; A Fluorescence Study on Guest Release of Reduction-responsive Host-guest Conjugates Having a Disulfide Bond. Chemistry Letters 2022, 51, 859-861, 10.1246/cl.220259.
- Wang, X.; Wang, H.; Zhang, M.; A multi-stimuli-responsive nanochannel inspired by biological disulfide bond. Talanta 2023, 265, 124785, 10.1016/j.talanta.2023.124785.