QUANTITATIVE DETERMINATION OF ASCORBIC ACID IN A DIETARY SUPPLEMENT VITAMINNI BY HPLC METHOD

421 Volume 5, Issue 10: Special Issue (EJAR) ISSN: 2181-2020 MPHAPP THE 6TH INTERNATIONAL SCIENTIFIC AND PRACTICAL CONFERENCE “MODERN PHARMACEUTICS: ACTUAL PROBLEMS AND PROSPECTS” TASHKENT, OCTOBER 17, 2025 in-academy.uz QUANTITATIVE DETERMINATION OF ASCORBIC ACID IN A DIETARY SUPPLEMENT VITAMINNI BY HPLC METHOD Tleubaeva N.J. Khamdamov M.M. Tashkent Pharmaceutical Institute, e-mail: [email protected] tel: (91) 302-07-27 https://doi.org/10.5281/zenodo.17341411 Relevance: Gummy dietary supplements in the form of jelly bears represent a modern and convenient dosage form of vitamin-mineral complexes. One of the most demanded components of such supplements is ascorbic acid (vitamin C), which possesses pronounced antioxidant properties and is involved in numerous metabolic processes of the human body. To control the quality of such dietary supplements, it is necessary to use highly accurate analytical methods, among which the most sensitive is the high-performance liquid chromatography (HPLC) method. Aim of the study: Quantitative determination of ascorbic acid in the dietary supplement VitaMinni (gummy bears) using HPLC. Methodology: • Chromatographic conditions: HPLC system equipped with a UV detector; C18 column (150×4.6 mm, 5 µm); mobile phase – phosphate buffer solution with pH 3.0 : acetonitrile (60:40); flow rate – 1.0 ml/min; injection volume – 20 µl; detection – UV at 265 nm. • Standard solution: about 50 mg (accurately weighed) of standard ascorbic acid was placed into a 50 ml volumetric flask, dissolved in 25 ml of water, and the volume was adjusted to the mark with the same solvent (final concentration: 1.0 mg/ml). • Test solution: about 3 g (accurately weighed) of VitaMinni gummy bears were finely ground and quantitatively transferred into a 100 ml volumetric flask using 50 ml of water, dissolved with ultrasonic assistance, the volume was made up to the mark with the same solvent, mixed, and filtered through a 0.45 µm membrane filter. Peak area of standard sample solution: Peak area of the test solution: 422 Volume 5, Issue 10: Special Issue (EJAR) ISSN: 2181-2020 MPHAPP THE 6TH INTERNATIONAL SCIENTIFIC AND PRACTICAL CONFERENCE “MODERN PHARMACEUTICS: ACTUAL PROBLEMS AND PROSPECTS” TASHKENT, OCTOBER 17, 2025 in-academy.uz Results: The average weight of the gummy bears was 3.105 g. Authenticity: The retention time of the main peak on the chromatogram of the test solution prepared for quantitative determination corresponded to the retention time of the main peak in the chromatogram of the reference solution. The content of ascorbic acid in one VitaMinni gummy was 10.4 mg. The quantitative determination results are presented in the table below. Table №1 Accurately weighed samples taken, gr Retention times, min Peak areas of solutions Standard samples 0,0501 0,950 9592307 0,0504 0,956 9631081 0,0502 0,952 9592685 Test samples 3,2962 0,948 1102056 3,1586 0,940 978908 3,2271 0,946 1039393 Conclusion: the HPLC method provides reliable and accurate determination of ascorbic acid content in the jelly forms of VitaMinni and can be recommended for the quality control of dietary supplements in gummy formulations.