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Endohedral fullerenes (EEFs) are of particular interest for researchers because their molecules have a unique structure and, so, physicochemical properties. The chemical elements used to alloy the electrodes give new properties to the spherical molecules formed during the synthesis process. In this direction, there are still many unsolved problems related to the understanding of the processes that take place in the carbon plasma containing impurities of different chemical composition, as well as the processes of extraction, isolation, separation and identification of products. The research focused on optimizing the conditions for the synthesis of EEF-containing carbon black (a mixture of products formed during the arc synthesis of endometallofullerenes), the development of new approaches to the synthesis of EEF derivatives and of effective methods for extracting EEF from synthesis products. Quick identification of the resulting product will accelerate research in this area. The aim of the study was to examine the electronic absorption spectra of the extracts obtained by isolating endometallofullerenes and fullerenes from carbon black obtained in the experiments. This is necessary to identify the characteristics of their absorption spectra for further use to determine the synthesized products by spectrophotometric method. Endohedral fullerenes were obtained by the most common and productive method of electric arc synthesis. The paper describes the study of materials formed by the joint arc evaporation of graphite and metals. The scheme of two-stage extraction of EEF from fullerene-containing carbon black was used, which made it possible to obtain dimethylformamide (DMF) solutions of practically pure endometallofullerenes. A possibility of using spectrometry for the identification of endometallofullerenes has been shown and it is proposed to use the spectrophotometric method for their detection. It has been found that the purest fullerites are formed under conditions if extraction and crystallization are carried out at the lowest possible temperatures. [ABSTRACT FROM AUTHOR]