Smartphone use in solid-phase fluorimetric determination of some polypeptide antibiotics in medicinal preparations

The analysis of semi-products at different stages of production and finished medicinal products is an integral part of an effective quality assurance system for pharmaceutical production. The traditional methods used in the pharmaceutical field, such as capillary electrophoresis, gas and liquid chromatography, are quite versatile and effective. However, they are distinguished by the high cost of instrumentation and component materials, the need to use high-purity solvents, the lack of mobility and the possibility of in situ studies. Such shortcomings can be overcome by using the digital colorimetry method. Its significant popularization has been facilitated by the development of portable and personal electronic devices, among which the smartphone can be distinguished. The aim of the work was to develop a fast and simple method for the determination of a number of polypeptide antibiotics in drugs by digital colorimetry using a smartphone as a color recording device. To implement the solid phase fluorimetric determination of polypeptide antibiotics, HPTLC plates based on silica gel with an aluminum substrate were used as a matrix. Under these conditions, the fluorescence of actinomycin D, virginiamycin M1, virginiamycin S1, and novobiocin was observed when exposed to monochromatic radiation in the UV part of the spectrum (365 nm). The measurement of fluorescence intensity on the surface of the matrices was carried out using a smartphone. Calibration characteristics were constructed for the determination of polypeptide antibiotics in the concentration range of 32–500 μg/mL. The method for assessing the quality of finished drugs was tested on commercial products “Piostacin”, “Cosmegen”, “Dactinomycin” purchased in retail chains. The relative standard deviation of the analysis results does not exceed 0.05. The duration of the analysis was 10–15 min. Based on the results of the studies, the paper presents a method for determining some antibiotics of the polypeptide series by the intrinsic fluorescence of deposited solutions on a solid substrate during treatment with monochromatic UV radiation. The experimental delivery conditions used allow the analysis of drugs based on actinomycin D, virginiamycin M1, virginiamycin S1, and novobiocin.