| |
 |
UNIVERSITY OF BUCHAREST
FACULTY OF PHYSICS Guest
2024-11-23 17:46 |
 |
|
|
|
Conference: Bucharest University Faculty of Physics 2017 Meeting
Section: Optics, Spectroscopy, Plasma and Lasers
Title:
Time stability of laser exposed phenothiazines aqueous solutions
Authors:
Tatiana Tozar (1), I. R. Andrei(1), M. L. Pascu (1,2)
Affiliation:
1)National Institute for Laser, Plasma and Radiation Physics, Magurele, Romania
2)Faculty of Physics, University of Bucharest, Magurele, Romania
E-mail
tatiana.alexandru@inflpr.ro
Keywords:
Chlorpromazine, thioridazine, time stability, laser exposure
Abstract:
Time stability of medicine solutions is an important feature of the quality of pharmaceutical products; therefore, its testing plays a crucial role in the development and use of medicines. The purpose of stability testing is to provide information on how the quality of an irradiated drug substance varies over time under the influence of environmental factors such as temperature, humidity and light, and to establish an optimal test period, the storage conditions and the time interval within which the medicine may be used, particularly if it is administrated as solution. For instance, before using irradiated phenothiazines on cell cultures, it is necessary to carry out a sample time stability study in order to identify the timeframe in which, after irradiation, the solutions remain stable and can be used. UV-Vis-NIR absorption spectroscopy resulted to be an appropriate method for investigating the time stability of the analyzed aqueous solutions. The time stability of non-irradiated and irradiated aqueous solutions of chlorpromazine (CPZ) and thioridazine (TZ) was determined by UV-Vis-NIR absorption spectroscopy. CPZ and TZ solutions having a concentration of 2 mg/mL were irradiated using laser beam emission at 266 nm, pulse average energy of 6.5 mJ, laser exposure periods ranging from 1 to 240 min. Stability studies over time were performed by recording the UV-Vis-NIR absorption spectra immediately (0 h) at 24 h, 48 h, 1 week, 2 weeks, 3 weeks, and 4 weeks after the irradiation process was completed. The CPZ and TZ samples were stored in the dark at 4°C. In conclusion, the irradiated solutions can be used to test the sensitivity of microorganisms to CPZ and TZ after 24 h and no later than 2 weeks.
Acknowledgement:
This work has been financed by the National Authority for Research and Innovation in the frame of Nucleu programme-contract 4N/2016 and project PN-III-P2-2.1-PED-2016-0420.
|
|
|
|