Actual problems of modern science, education and training

Literature Review. Azo chemical compounds are still at the center of scientific research, particularly azo dyes, a class of synthetic, colored organic compounds containing one or more azo bonds (-N=N-) is a particularly noteworthy direction [1,2].
These azo groups form bridges between organic residues, at least one of which is usually an aromatic nucleus. Basically, the production of azo dyes is based on the coupling of diazonium compounds with phenols, naphthols, arylamines, pyrazolones or other suitable components, and focuses on the formation of hydroxyazo, aminoazo compounds or their tautomers. The chemistry of these dyes ranges from simple monoazo compounds to complex polyazo compounds with a molecular weight of 2000 or more [3]. Azo dyes are the most important class of organic dyes, and they are widely used in many fields: various fields (textiles, polymers, photography, printing and ceramics), optical fields (lasers, optical sensors, photochromic materials), in almost all food and cosmetics, drugs (pharmaceutical products, photodynamic therapy, antimicrobial activity), etc. [4-8]. Usually, metal complexes of azo dyes are formed by the reaction of intermediate metal ions with ligands, where the ortho positions close to the azo group contain groups that can form coordination with metal ions. Such groups include hydroxyl (-OH) carboxy (-COOH) amino (-NHR) and oxy-acetic (- OCH₂COOH) groups. These organic azo dyes with functional analytical active groups are used in sorption-spectroscopic determination of toxic metal ions in various water samples.
As a method of controlling the content of toxic elements, including lead ions in waste water, industrial water and natural water, it is possible to use the method of continuous monitoring and rapid control of elements.
Research on the creation of reagents immobilized on various polymer sorbents for the detection of heavy toxic metal ions is currently one of the actively developing areas of analytical chemistry [9-12]. As a rule, these studies are carried out at the intersection of several disciplines: organic, inorganic chemistry, chemistry of polymers, biology and medicine [13]. This method is carried out using sorbents using certain physico-chemical methods and analysis. As sorbents, polycrystalline films of chalcogenides and metal oxides with a thickness of 30-2000 nm are used, on which an inert fiber or solid base is applied, and they are also used as cellulose and its derivatives, glass, polymers and other materials. This new method applies to the management of waste, industrial water and natural water environment, and can be used (and intended) for continuous monitoring and rapid control of toxic and radioactive elements [7].