A Self-Degradable Hydrogel Sensor for a Nerve Agent Tabun Surrogate Through a Self-Propagating Cascade

SUMMARYNerve agents which irreversibly deactivate the enzyme acetylcholinesterase are extremely toxic weapons of mass destruction. Thus, developing methods to detect these lethal agents are important. To create an optical sensor for a surrogate of the nerve agent tabun, as well as a physical barrier that dissolves in response to this analyte, we devised a network hydrogel that decomposes via a self-propagating cascade. A Meldrum’s acid-derived linker was incorporated into a hydrogel which undergoes a declick reaction in response to thiols, thereby breaking network connections, which release more thiols; propagating the response throughout the gel. A combination of chemical reactions triggered by the addition of the tabun mimic initiates the cascade. The dissolving barrier was used to release dyes, as well as nanocrystals that undergo a spontaneous aggregation. Thus, this sensing system for tabun generates a physical response and the delivery of chemical agents in response to an initial trigger.