Metal Organic Frame works using for the destruction of Chemical Weapons

In mid-march, a village called Sarmin, in Northwestern Syria was attacked by bombers from a helicopter. There is no explosion, no fire but it was the most worst form of attack where the civilians did not injured by physical wounds. But their struggle started after a few minutes who rushed to the nearest hospitals as they suffered from various ailments such as severe coughing, burning sensation in eyes and throat and most of them were unable to breathe. 

“There was a very strong chlorine smell there,” Muhammad Yazan, a local activist, told Human Rights Watch. Yazan went to the impact site in Sarmin, as well as to another village that was attacked in Idlib province. “One of our team members passed out due to the smell. It was horrible. My eyes were burning. I wanted to throw up. My skin felt like I had rashes.”

By the time the attacks ended, six civilians — including three children — were dead and at least 110 others were struggling with various symptoms associated with a chlorine attack. Later it was revealed that it was not caused by Chlorine, because using chlorine has several uses like cleaning of drinking water and it has bleaching properties. The gas bombers contain various chemical warfare agents which also called as nerve agents. "Paraoxon" is one of the important nerve agent regularly used as a component of chemical weapons. Its chemically called as "Dimethyl 4-nitrophenyl phosphate (DMNP). It is a parasympathomimetic agent which acts as acetylcholineesterase inhibitor. It is an organophosphate oxon, and the activemetabolite of the insecticide parathion. It is also used as an ophthalmological drug against glaucoma. Paraoxon is one of the most potent acetylcholinesterase-inhibiting insecticides available, around 70% as potent as the nerve agent sarin, and so is now rarely used as an insecticide due to the risk of poisoning to humans and other animals. It is easily absorbed through skin, and was used as an assassination weapon by the apartheid-era South African chemical weapons program Project Coast.

Dimethyl 4-nitorphenyl phosphate (DMNP/paraoxon)

Victim of recent Syrian War ; Source @Frontline (www.pbs.org)

To destroy these chemical weapons, US researchers developed Metal Organic Frameworks (MOF) which have the ability to breakdown rapidly the nerve agents. Scientists were saying these MOFs are becoming an essential tools to destory chemical weapons. Omar Farha and his colleagues from Northwestern University and University of Minnesota have demonstrated how Zirconium (Zr) based MOF takes just minutes to destroy Soman (GD), a more toxic chemical cousin to Sarin. Moreover, their computer simulations show the same material - NU-1000- should be effective against various other agents like VX. The scientists are planning to incorporate these frameworks into gas masks and use them in bulk to destroy stock piled chemical weapons.

Molecular Framework (MOG) (c) NPG

Zirconium based molecular framwork

"This designed material is thermally and chemically robust, and it doesn't care what conditions it is in", explains Farha. "The material can be in water or a very humid environment, at a temperature of 130 degrees or minus 15, or in a dust storm. A soldier should not need to worry about under what conditions his protective mask will work." [Farha et al., Nature Mater, 2015, online; DOI: 10.1038/NMAT4238]

References:

1. S-Y Moon et al, Angew. Chem., Int. Ed., 2015, DOI: 10.1002/anie.201502155

2. Farha et al., Nature Mater, 2015, online; DOI: 10.1038/NMAT4238