Supramolecular Sensing of Chemical Warfare Agents

Abstract

Chemical warfare agents are a class of organic molecules used as chemical weapons due to their high toxicity and lethal effects. For this reason, the fast detection of these compounds in the environment is crucial. Traditional detection methods are based on instrumental techniques, such as mass spectrometry or HPLC, however the use of molecular sensors able to change a detectable property (e. g., luminescence, color, electrical resistance) can be cheaper and faster. Today, molecular sensing of chemical warfare agents is mainly based on the “covalent approach”, in which the sensor reacts with the analyte, or on the “supramolecular approach”, which involves the formation of non‐covalent interactions between the sensor and the analyte. This Review is focused on the recent developments of supramolecular sensors of organophosphorus chemical warfare agents (from 2013). In particular, supramolecular sensors are classified by function of the sensing mechanism: i) Lewis Acids, ii) hydrogen bonds, iii) macrocyclic hosts, iv) multi‐topic sensors, v) nanosensors. It is shown how the supramolecular non‐covalent approach leads to a reversible sensing and higher selectivity towards the selected analyte respect to other interfering molecules.

State of Art Technology: Synthesis of Carbon Dots and Their Potential Applications in Biomedical, Research and Environmental Remediation

“…Similarly, Paul et al, used gold nanoparticles for the detection and degradation of chemical warfare stimulants [24]. Butera et al, also summarized the importance of CDs in supramolecular sensing of chemical warfare agents [23].…”

“…The most recent application of CDs is in the field of chemical warfare agents, especially for the detection of hazardous chemicals. These CDs were used either functionalized and non-surface modified forms which was reported by Kumar [23][24][25][26][27][28].…”

Metal Oxide Nanosystems As Chemoresistive Gas Sensors for Chemical Warfare Agents: A Focused Review

“…Chemical weapons [(chemical warfare agents (CWAs)] developed to kill or incapacitate potential enemies [2][3][4][5] were introduced for military purposes in World War I (1915-1918) and killed over 90 000 people. [6,7] Subsequently, during the 1930s, Germans manufactured nerve agents [8] which were further targeted by the British (1950s) and weaponized by the Americans. [9] The production of such compounds continued throughout the Cold War, subsequently leading to stockpiles of arsenals in U.S. and Russian military deposits.…”

“…the hands of terrorists, and their recurring use makes them a contemporary and persistent hazard. [8,13,[23][24][25][26][27] Examples in this regard include nerve agents release in Japan (Matsumoto, 1994 andTokyo, 1995), [2][3][4][36][37][38][39][40] Al Qaeda threats, [41] the assassination of Kim Jong-Nam, the half-brother of North Korean leader Kim Jong-un, at Kuala Lumpur Airport (Malaysia) in 2017, [42,43] and the poisoning of the Russian spy Sergei Skripal and his daughter in Salisbury (UK) in 2018. [44] Highly lethal CWAs, that can be classified into four main categories (see Table 1; nerve, blood, vesicant, and choking agents [2,4,5,10,17,28,[45][46][47][48] ) can burn and blister skin/eyes, enter into the body in blood and attack the nervous system.…”

Agile Detection of Chemical Warfare Agents by Machine Vision: a Supramolecular Approach

“…Notably, calculated limit of detection is 9.47 ppt, many orders of magnitude lower than the IDLH (concentration of toxin in air that is immediately dangerous to life and health) values of the common CWAs (2–30 ppb). [31] …”