Metal–Organic Framework Modified Glass Substrate for Analysis of Highly Volatile Chemical Warfare Agents by Paper Spray Mass Spectrometry

Abstract

Paper spray mass spectrometry has been shown to successfully analyze chemical warfare agent (CWA) simulants. However, due to the volatility differences between the simulants and real G-series (i.e., sarin, soman) CWAs, analysis from an untreated paper substrate proved difficult. To extend the analytical lifetime of these G-agents, metal-organic frameworks (MOFs) were successfully integrated onto the paper spray substrates to increase adsorption and desorption. In this study, several MOFs and nanoparticles were tested to extend the analytical lifetimes of sarin, soman, and cyclosarin on paper spray substrates. It was found that the addition of either UiO-66 or HKUST-1 to the paper substrate increased the analytical lifetime of the G-agents from less than 5 min detectability to at least 50 min.

Fabrication of carboxymethylated cellulose fibers supporting Ag NPs@MOF‐199s nanocatalysts for catalytic reduction of 4‐nitrophenol

“…As shown in Figure a, the characteristic peaks of MOF‐199 s (2θ = 6.7°, 9.5°, 11.7°, 13.3°, 14.6°, 16.6°, 17.3°, 18.9°, 25.8° and 29.2°), were evident. For the Ag NPs@MOF‐199 s (Figure b), those peaks of MOF‐199 s in Figure a were confirmed, supporting the conclusion that the immobilization of Ag NPs onto the porous MOF‐199 s does not change their crystal structures.…”

On‐substrate derivatization for detection of highly volatile G‐series chemical warfare agents via paper spray mass spectrometry

“…While these two compounds have differing volatilities, previous experiments have indicated that GB and GF volatilize rapidly . Albeit with differing rates of volatility, the derivatization process allows for their direct capture on the PS substrate and retainment of the derivatized compound due to the lower volatility of the resulting complex.…”

“…More relevantly, explosives, herbicides from aqueous matrices, pesticides, and CWA simulants from biofluids have been shown to be effectively analyzed via paper spray mass spectrometry (PS‐MS). The spray substrate has been subjected to a multitude of modifications including the addition of metal–organic‐frameworks (MOFs), carbon nanotubes, silica, urea, silanes, molecularly imprinted polymer (MIPs), and wax printing, with each resulting in a specialized system catering to a specific matrix or target chemistry. For example, these innovative modifications have allowed for sub‐parts‐per‐trillion detections of therapeutic drugs .…”

“…G‐series agents have proven difficult to analyze via PS‐MS, due to their short analytical lifetimes before dissipating . Modification of the substrate with MOFs has extended the analytical lifetime to 60 min, enabling the direct detection of the native G‐series agent . An alternative approach is to derivatize the G‐series agent upon contact with the paper substrate, changing the chemical properties by decreasing the volatility, while foregoing the direct detection of the native molecule.…”

Emerging trends in paper spray mass spectrometry: Microsampling, storage, direct analysis, and applications

“…The chosen material is suspended into an aqueous starch solution, sonicated, possibly heated to boiling (Wang et al, ), and then added to the Buchner funnel containing a filter paper. Coating materials of silica particles (Wang et al, ), metal organic frameworks (MOFs) (Wang et al, ; Dhummakupt et al, ), metal oxides (Zheng et al, ,b), and polystyrene (Wang et al, ; Li et al, ) were studied. Silica particles were observed to fill pores and rest on the paper surface, adhered by the starch (Zheng et al, ).…”