Dual-channel discrimination of two lethal chemical warfare agents using an ESIPT-ICT-based fluorescent probe.

Among all kinds of chemical warfare agents, only cyanide and nerve agents can cause massive mortality at low concentrations. In this work, a dual-channel fluorescent probe CWAs-Thia capable of detecting cyanide and nerve agents is presented. The two reactive recognition units, pyridine and the thiazole-2-carbonyl group, of the probe for cyanide and nerve agents, respectively, produced red and blue fluorescent responses, respectively, which were attributed to excited-state intramolecular proton transfer and intramolecular charge transfer. CWAs-Thia is the first probe that can selectively recognize cyanide and nerve agent. And it has proven to be effective in visualizing cyanide and nerve agents in living cells.

Development of a Multiparticulate Metal-Organic Framework/Textile Fiber Swatch.

The versatility of metal-organic frameworks (MOFs) has led to groundbreaking applications in a wide variety of fields, especially in the areas of energy, environment, and sustainability. For example, MOFs can be designed for high uptake of toxic gases and pollutants, such as CO2, NH3, and SO2, but designing a single MOF that shows tangible uptake for all of these gases is challenging due to the differences in the chemical and physical properties of these molecules. To this end, integrating multiple MOFs onto textile fibers and crafting various structures have emerged as pivotal developments, enhancing framework durability and usability. MOF composites prepared on readily available textile fibers offer the flexibility essential for critical applications, including heterogeneous catalysis, chemical sensing, toxic gas adsorption, and drug delivery, while preserving the unique characteristics of MOFs. This study introduces a scalable and adaptable method for seamlessly embedding multiple high-performing MOFs onto a single textile fiber using a dip-coating method. We explored the uptake capacity of these multi-MOF composites for CO2, NH3, and SO2 and observed a performance similar to that of traditional powdered materials. Along with harmful gas adsorption, we also have evaluated the permeation and reactivity of these MOF/textile composites toward chemical warfare agents (CWAs) like GD (soman), HD (mustard gas), and VX. In combination, these results demonstrate a fundamental advancement toward establishing a consistent strategy for the hydrolysis of nerve agents in real-world scenarios. This approach can substantially increase the protection toward CWAs and enhance the effectiveness of protective equipment such as fabrics for protective garments. This dip-coating method for the integration of multiple MOFs on a single textile fiber unlocks a wealth of possibilities and paves the way for future innovations in the deployment of MOF-based composites.

Novel Application of Metal-Organic Frameworks as Efficient Sorbents for Solid-Phase Extraction of Chemical Warfare Agents and Related Compounds in Water Samples.

In this work, we test metal-organic frameworks (MOFs) as sorbents in the solid-phase extraction (SPE) technique to determine chemical warfare agents (CWAs) and their related compounds in water samples. During this study, we used 13 target compounds to test the selectivity of MOFs thoroughly. Three MOFs were used: MIL-100(Fe), ZIF-8(Zn), and UiO-66(Zr). The obtained materials were characterized using FT-IR/ATR, SEM, and XRD. CWA's and related compounds were analyzed using gas chromatography coupled with tandem mass spectrometry (GC-MS/MS). The effect of the type of elution solvent and the amount of sorbent (MOFs) in the column on the efficiency of the conducted extraction were verified. The LOD ranged from 0.04 to 7.54 ng mL-1, and the linearity range for the analytes tested extended from 0.11/22.62 (depending on the compound) to 1000 ng mL-1. It was found that MOFs showed the most excellent selectivity to compounds having aromatic rings in their structure or a "spread" spatial structure. The best recoveries were obtained for DPAA, CAP, and malathion. Environmental water samples collected from the Baltic Sea were analyzed using an optimized procedure to verify the developed method's usefulness.

Three-dimensional photonic crystal optical gas sensor for trace detection and ultrafast response of chemical warfare agent in atmospheric humidity.

Chemical warfare agents (CWAs) are toxic that pose a threat to the environment and human health, even trace amounts of CWAs can be fatal. In view of this, there is an urgent need to develop gas sensors for trace detection and ultrafast response of CWAs. Herein, an optical gas sensor has been proposed based on metal-organic frameworks (MOFs) three-dimensional (3D) photonic crystal to detect trace CWAs' simulant (dimethyl methylphosphonate, DMMP) in different atmospheric humidity (RH 20 %, RH 40 %, RH 60 %, RH 80 %). At relative humidity (RH) of 20 %, the sensor shows excellent selectivity of DMMP due to the specific interactions of van der Waals force between UiO-67 and phosphoryl oxygen (OP) group of DMMP (C3H9O3P), the ultrahigh sensitivity (42.7 ppb), ultrafast response (0.5 s) are profit from the ordered superstructure of 3D photonic crystal and its complete photonic bandgap. At higher humidity (RH 40%-80 %), the sensor shows excellent stability, long-term repeatability, and it still keeps ultrahigh sensitivity (12.1 ppb), ultrafast response (0.49 s) for DMMP at RH 80 %. Moreover, an optical gas sensor array has been prepared to solve the problem of cross-sensitive between DMMP and other CWAs at highest humidity (RH ≥ 80 %), the average classification accuracy can reach 98.6 %.

UV-Cured Highly Crosslinked Polyurethane Acrylate to Serve as a Barrier against Chemical Warfare Agent Simulants.

Ultraviolet (UV) curing is an efficient and environmentally friendly curing method. In this paper, UV-cured polyurethane acrylates (PUAs) were investigated as potential military coatings to serve as barriers against chemical warfare agents (CWAs). Seven UV-cured PUA coatings were formulated utilizing hydroxyethyl methacrylate-capped hexamethylene diisocyanate trimer (HEMA-Htri) and trimethylolpropane triacrylate-capped polycarbonate prepolymer (PETA-PCDL) as the PUA monomers. Isobornyl acrylate (IBOA) and triethyleneglycol divinyl ether (DVE-3) were employed as reactive diluents. Gas chromatography was utilized to investigate the constitutive relationships between the structures of the PUA coatings and their protective properties against simulant agents for CWAs, including dimethyl methylphosphonate (DMMP), a nerve agent simulant, and 2-chloroethyl ethyl sulfide (CEES), a mustard simulant. The glass transition temperature (Tg) and crosslinking density (υe) of PUAs were found to be crucial factors affecting their ability to serve as barriers against CWAs. The incorporation of IBOA units led to enhanced Tg and barrier performance of the PUAs, resulting in a DMMP retention of less than 0.5% and nearly 0 retention of CEES. However, an excessive introduction of polycarbonate chains decreased the υe and barrier performance of the PUAs. These findings may offer valuable insights for enhancing the protection of UV-cured PU coatings against CWAs.

Highly Efficient Separation of Ethanol Amines and Cyanides via Ionic Magnetic Mesoporous Nanomaterials.

Simple and efficient sample pretreatment methods are important for analysis and detection of chemical warfare agents (CWAs) in environmental and biological samples. Despite many commercial materials or reagents that have been already applied in sample preparation, such as SPE columns, few materials with specificity have been utilized for purification or enrichment. In this study, ionic magnetic mesoporous nanomaterials such as poly(4-VB)@M-MSNs (magnetic mesoporous silicon nanoparticles modified by 4-vinyl benzene sulfonic acid) and Co2+@M-MSNs (magnetic mesoporous silicon nanoparticles modified by cobalt ions) with high absorptivity for ethanol amines (EAs, nitrogen mustard degradation products) and cyanide were successfully synthesized. The special nanomaterials were obtained by modification of magnetic mesoporous particles prepared based on co-precipitation using -SO3H and Co2+. The materials were fully characterized in terms of their composition and structure. The results indicated that poly(4-VB)@M-MSNs or Co2+@M-MSNs had an unambiguous core-shell structure with a BET of 341.7 m2·g-1 and a saturation magnetization intensity of 60.66 emu·g-1 which indicated the good thermal stability. Poly(4-VB)@M-MSNs showed selective adsorption for EAs while the Co2+@M-MSNs were for cyanide, respectively. The adsorption capacity quickly reached the adsorption equilibrium within the 90 s. The saturated adsorption amounts were MDEA = 35.83 mg·g-1, EDEA = 35.00 mg·g-1, TEA = 17.90 mg·g-1 and CN-= 31.48 mg·g-1, respectively. Meanwhile, the adsorption capacities could be maintained at 50-70% after three adsorption-desorption cycles. The adsorption isotherms were confirmed as the Langmuir equation and the Freundlich equation, respectively, and the adsorption mechanism was determined by DFT calculation. The adsorbents were applied for enrichment of targets in actual samples, which showed great potential for the verification of chemical weapons and the destruction of toxic chemicals.

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 and mice. 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.

Bayesian predictive modeling for gas purification using breakthrough curves.

This study proposes a predictive model for assessing adsorber performance in gas purification processes, specifically targeting the removal of chemical warfare agents (CWAs) using breakthrough curve analysis. Conventional parameter estimation methods, such as Brunauer-Emmett-Teller analysis, encounter challenges due to the limited availability of kinetic and equilibrium data for CWAs. To overcome these challenges, we implement a Bayesian parametric inference method, facilitating direct parameter estimation from breakthrough curves. The model's efficacy is confirmed by applying it to H2S purification in a fixed-bed setup, where predicted breakthrough curves aligned closely with previous experimental and numerical studies. Furthermore, the model is applied to sarin with ASZM-TEDA carbon, estimating key parameters that could not be assessed through conventional experimental techniques. The reconstructed breakthrough curves closely match actual measurements, highlighting the model's accuracy and robustness. This study not only enhances filter performance prediction for CWAs but also offers a streamlined approach for evaluating gas purification technologies under limited experimental data conditions.

Chloropicrin induced ocular injury: Biomarkers, potential mechanisms, and treatments.

Ocular tissue, especially the cornea, is overly sensitive to chemical exposures. The availability and adoption of chemical threat agent chloropicrin (CP) is growing in the United States as a pesticide and fumigant; thereby increasing the risk of its use in warfare, terrorist attacks and non-intentional exposure. Exposure to CP results in immediate ocular, respiratory, and dermal injury; however, we lack knowledge on its mechanism of toxicity as well as of its breakdown products like chlorine and phosgene, and effective therapies are elusive. Herein, we have reviewed the recent findings on exposure route, toxicity and likely mechanisms of CP induced ocular toxicity based on other vesicating chemical warfare agents that cause ocular injury. We have focused on the implication of their toxicity and mechanistic outcomes in the ocular tissue, especially the cornea, which could be useful in the development of broad-spectrum effective therapeutic options. We have discussed on the potential countermeasures, overall hallmarks and challenges involved in studying ocular injuries from chemical threat agent exposures. Finally, we reviewed useful available technologies and methods that can assist in the identification of effective medical countermeasures for chemical threat agents related ocular injuries.

An innovative Fuller's earth-based film-forming formulation for skin decontamination, through removal and entrapment of an organophosphorus compound, paraoxon-ethyl.

Organophosphorus compounds (OPs), such as VX, pose a significant threat due to their neurotoxic and hazardous properties. Skin decontamination is essential to avoid irreversible effects. Fuller's earth (FE), a phyllosilicate conventionally employed in powder form, has demonstrated decontamination capacity against OPs. The aim of this study was to develop a formulation that forms a film on the skin, with a significant OP removal capacity (>95 %) coupled with sequestration capabilities, favorable drying time and mechanical properties to allow for easy application and removal, particularly in emergency context. Various formulations were prepared using different concentrations of polyvinyl alcohol (PVA), FE and surfactants. Their removal and sequestration capacity was tested using paraoxon-ethyl (POX), a chemical that simulates the behavior of VX. Formulations with removal capacity levels surpassing 95 % were mechanically characterized and cell viability assays were performed on Normal Human Dermal Fibroblast (NHDF). The four most promising formulations were used to assess decontamination efficacy on pig ear skin explants. These formulations showed decontamination levels ranging from 84.4 ± 4.7 % to 96.5 ± 1.3 %, which is equivalent to current decontamination methods. These results suggest that this technology could be a novel and effective tool for skin decontamination following exposure to OPs.