| Abstract [eng] |
Master‘s thesis of Alicija Gurskaitė „Investigation of the Impact of Packaging on the Photostability of Antihypertensive Tablets”. Supervisor: doc. dr. Nora Šlekienė. Vilnius University, Faculty of Medicine, Institute of Biomedical Sciences, Pharmacy and Pharmacology Center. Aim: to evaluate the impact of primary packaging (blister) and red, green, yellow filters on the photostability of amlodipine, losartan and metoprolol tablets. Objectives: 1.To evaluate the impact of primary packaging on the physical and chemical photostability of amlodipine, losartan and metoprolol tablets exposed to natural radiation during summer, autumn and winter seasons. 2. To evaluate the impact of primary packaging on the physical and chemical photostability of amlodipine, losartan and metoprolol tablets exposed to artificial UV–C (254 nm) radiation for 24, 48 and 72 hours. 3.To determine the protective effect of red, green, yellow filters on the physical and chemical photostability of amlodipine, losartan and metoprolol tablets exposed to natural radiation during summer, autumn and winter seasons. 4.To determine the protective effect of red, green, yellow filters on the physical and chemical photostability of amlodipine, losartan and metoprolol tablets exposed to artificial UV–C (254 nm) radiation for 24, 48 and 72 hours. Methods: tablets stored without packaging, in primary packaging, and in primary packaging covered with red, green, yellow filters were exposed to natural radiation during summer, autumn and winter seasons and to artificial UV–C (254 nm) radiation for 24, 48 and 72 hours. After exposure, tablet color changes were assessed visually, surface morphological defects were recorded by scanning electron microscopy. Changes in the absorption of the active substances were determined by UV–Vis spectroscopy, and photodegradation was evaluated by calculating the degree of photodegradation. Results: under natural radiation, the greatest color change was observed in unpacked amlodipine tablet stored in summer and the most pronounced morphological defects were observed in unpacked losartan tablets stored during summer and autumn. The highest photodegradation of amlodipine and losartan was determined in summer blister samples, reaching 27.7% and 33.2%, respectively, while that of metoprolol in the unpacked summer sample (35%). Under artificial radiation, packed tablets showed no color changes and a microcrack was recorded only in the unpacked losartan tablet after 72 hours. The highest photodegradation was determined in unpacked samples after 72 hours: amlodipine–17.4%, losartan–15.6%, and metoprolol–15.4%. Under natural and artificial radiation, the green filter most reduced physical changes and photodegradation in amlodipine and losartan tablets: in winter, it reached 4.2% and 5.7%, respectively, and after 24 hours, 0.9% and 5.5%, respectively. The yellow filter best protected metoprolol tablets from physical changes with the lowest photodegradation observed in the winter sample (3.7%) and after 24 hours (4.9%). Conclusions: 1. In summer, autumn and winter, primary packaging reduced tablet color changes and morphological defects in losartan tablets but chemically its protective effect was found only in autumn and winter metoprolol samples. 2. After 24, 48 and 72 hours, primary packaging protected amlodipine tablets from color changes and losartan tablets from morphological defects and reduced photodegradation of all substances. 3.In all seasons, the green filter most reduced color and chemical changes in amlodipine and losartan tablets, while the yellow filter was most effective for metoprolol physical and chemical photostability. 4.After 24, 48 and 72 hours, the green filter was most effective in reducing amlodipine and losartan photodegradation, and the yellow filter – the photodegradation of metoprolol. |
