This work provides a summary of our results in the area of the experimental development of detection paper for the detection of liquid phase chemical warfare agents (drops, aerosol), the presence of which is demonstrated by the development of characteristic coloring visible to the naked eye. The basis of the detection paper is a cellulose carrier saturated with the dithienobenzotropone monomer (RM1a)–chromogenic chemosensor sensitive to nerve agents of the G type, blister agent lewisite, or choking agent diphosgene. We achieve a higher coloring brilliance and the limit certain interferences by using this chemosensor in the mix of the o-phenylendiamine-pyronine (PY-OPD). We prove that the addition of the Bromocresol Green pH indicator even enables detection of nerve agents of the V type, or, nitrogen mustards, while keeping a high stability of the detection paper and its functions for other chemical warfare agents. We resolve the resistance against the undesirable influence of water by providing a hydrophobic treatment of the carrier surface.

Colorimetric biosensors of cholinesterase inhibitors are ideal for fast, reliable, and very simple detection of agents in air, in water, and on surfaces. This paper describes an innovation of the Czech Detehit biosensor, which is based on a biochemical enzymatic reaction visualized by using Ellman’s reagent as a chromogenic indicator. The modification basically consists of a much more distinct color response of the biosensor, attained through optimization of the reaction system by using Guinea Green B as the indicator. The performance of the modified biosensor was verified on the chemical warfare agents (sarin, soman, cyclosarin, and VX) in water. The detection limits ascertained visually (with the naked eye) were about 0.001 µg/mL in water (exposure time 60 s, inhibition efficiency 25%).

This paper presents the results of experiments aiming for the detection and differentiation of selected nerve agents of the Novichok and V-group using simple strip detectors containing colourimetric indicator, specifically chemosensor Nile Blue A, immobilized in cellulose matrix. In all experimental modifications, the contact of the active zone of the strip detector and respective nerve agent excited an immediate development of significant colouration visible to the naked eye. Alkaline solutions containing various hydroxides, carbonates and bicarbonates, and/or chloramine B were used to demonstrate the relevant reaction. The proposed strip detectors indicate a promising approach towards the development of low-cost, easily portable, and usable means of detection of the respective nerve agents.

A group of highly potent synthetic opioids called nitazenes has been known to the public for several years. They were synthesized in the 1950s, but were never approved for use in human medicine due to their excessive toxicity and risk of addiction. Both the basic substance and its analogues are increasingly appearing on the illegal market and in cases of overdose in drug addicts. They are structurally different from fentanyl and its derivatives, but their effects are also related to their agonistic action on µ-opioid receptors in the central nervous system. They are strong analgesics with a rapid onset of action, which is associated with an extreme risk of respiratory depression and overdose. Some nitazene analogues can be many times more potent than fentanyl. Given that they represent a serious threat to public health and safety, current prevention focuses primarily on educating the population, the availability of an antidote, and the early detection and identification of new derivatives on the market.

In 2019, carbamates derived from 3-hydroxypyridine were classified as nerve agents and subsequently included in the Annex on Chemicals by the Conference of the States Parties. Herein, we describe the preparation of a structural simulant of this class of compounds, 10-hydroxy-N,N-dimethyl-N-((3-(tosyloxy)pyridin-2-yl)methyl)decan-1-aminium bromide. The compound was synthesized via tosylation of 2-((N,N-dimethylamino)methyl)pyridin-3-ol with tosyl chloride in the presence of sodium hydride, followed by alkylation of the resulting ((N,N-dimethylamino)methyl)pyridin-3-yl 4-methylbenzenesulfonate with 10-bromodecan-1-ol.