Visual detection and discrimination of nerve and blood agents using a dual-site fluorescent probe in living cells and mice

Of all chemical warfare agents (CWAs), only nerve and blood agents cause massive mortality at low concentrations. To better detect and discriminate nerve and blood agents, a reliable detection method is desirable. We report a series of fluorescent probes for nerve and blood agent detection. Among the tested probes, SR-Pip detected nerve and blood agents quickly (within 10 s for nerve agents and 1 min for blood agents). SR-Pip coupled with nerve agent produced a weak orange fluorescence with good sensitivity [limit of detection (LOD)=5.5 μM]. Upon reaction with blood agent, the fluorescence of SR-Pip changed from orange fluorescence to blue fluorescence with detection limits as low as 9.6 nM. This probe effectively visualised different concentrations of nerve agents in living cells, mice and blood. A portable test kit using SR-Pip instantly detected nerve and blood agents. To the best of our knowledge, SR-Pip is the first fluorescent probe for nerve and blood agent detection. Blood agents (also known as cyanide) are widely used in industrial chemicals. Accidental spills of cyanide solutions into rivers and streams have produced massive kills of fish and other aquatic biota. In addition, cyanide intoxication can occur under the conditions of terrorist activities, smoke inhalation, and even improperly prepared foods. Nerve agents are seldom used in industrial chemicals, but they are a class of highly toxic organophosphate compounds. Nerve agents remain a clear and present danger to both the military and citizens. Therefore, it is important to develop a convenient, accurate detection method for nerve and blood agents.