To control the concentration of drugs with a narrow therapeutic range, and to conduct effective and safe treatments, Therapeutic Drug Monitoring (TDM) is carried out. However, to date, the implementation of TDM is associated with various difficulties, for the solution of which more convenient and less invasive methods for collecting biological material are being developed.The aim of the study was to develop protocols for the collection and storage of “dried blood spot” (DBS) samples, as well as protocols for the validation methods for the quantitative determination of drugs in whole blood, using this technology for subsequent therapeutic drug monitoring.Materials and methods. To analyze a “dried blood spot” method in detail and to identify the characteristic features of taking and storing biosamples, a collection and analysis of scientific literature over the past 10 years has been conducted. The search for literature materials has been carried out from open and accessible sources located in the scientific libraries of institutions, in electronic databases and search engines: Elibrary, PubMed, Scopus, Cyberleninka, Medline, ScienceDirect, Web of Science, Google Scholar. Primary protocols for taking, storing and analyzing samples of the “dried blood drop” have been prepared. To obtain the adequate quality samples, the developed protocols have been tested and optimized at the stages of selection and storage. By high-performance liquid chromatography with mass spectrometric detection (HPLC-MS/MS), using a “dried blood drop” as a sample preparation, drug validation protocols have been optimized to ensure that acceptable validation characteristics were achieved, and subsequent Therapeutic Drug Monitoring was performed.Results. The features of the collection, storage and analysis of the “dried blood spot” samples have been revealed. Such characteristics as a spot volume effect, a hematocrit effect, a droplet uniformity, which can affect the results of a quantitative HPLC-MS/MS analysis, have been determined. For a successful use of the new methods, appropriate protocols for taking samples of “dried blood spot” from the finger of adult patients and from the heel of newborns, as well as protocols for validating methods for the quantitative determination of drugs from these samples, have been developed.Conclusion. The application of the “dried blood spot” method using newly developed protocols for taking, storing and analyzing biological samples, relieves the existing constraints in conducting TDM, and can later become a promising method for conducting preclinical and clinical studies.
