RAP Conference Proceedings, vol. 4, pp. 15–17, 2019 ISSN 2466-4626 (online) | doi: 10.37392/RapProc.2019.04 WWW.RAP-PROCEEDINGS.ORG ESR INVESTIGATION OF X-RAY EXPOSURE ON SOME ANTI-DIABETICS AND PROTON PUMP INHIBITORS E. Tugce Sarcan 1 , Asuman Tas 1 , Mine Silindir-Gunay 1 , A. Yekta Ozer 1* , Seyda Colak 2 , Baki Hekimoglu 3 1 Hacettepe University, Faculty of Pharmacy, Department of Radiopharmacy, Sihhiye, Ankara, Turkey 2 Hacettepe University, Faculty of Engineering, Department of Nuclear Physics, Beytepe, Ankara, Turkey 3 Health Sciences University, Diskapi Yildirim Beyazit and Education Research Hospital, Department of Radiology, Diskapi, Ankara, Turkey Abstract. X-ray is ionizing radiation used in several areas such as analytical sciences, medicine and security areas. X-ray machines are used in the entrance of important places (airports, shopping centers, etc.) for security purposes. The aim of this study was the investigation of the potential effects of X-ray irradiation on anti-diabetics (metformin HCl, pioglitazone HCl) and proton pump inhibitors (PPI) (lansoprazole, pantoprazole sesquihydrate) pharmaceuticals which are used in chronic diseases by Electron Spin Resonance (ESR). ESR analysis was done before and after different X-ray irradiation doses. Afterwards, ESR spectra and resonance peaks were evaluated. As a result, no significant free radicals were detected by ESR resonance peaks and also, their ESR intensities did not change significantly by increasing X-ray doses. Keywords: Electron Spin Resonance, X-ray, ionizing radiation, X-ray irradiation on pharmaceuticals * ayozer@hacettepe.edu.tr 1. INTRODUCTION X-ray irradiation having short wavelength and high penetration capability is used in several areas nowadays. Especially, it is used for security in several control points such as passenger bags screening at airports, shopping centers, etc., with evolving technologies [1]. X-ray exposure can cause the formation of reactive molecular fragments and induced radical types which can be determined previously by Electron Spin Resonance (ESR) spectroscopy [2,3]. ESR is a non- destructive, highly sensitive spectroscopic technique allowing direct observation of free radicals and enabling the differences between radical types. Thus, this method is accepted to be one of the most reliable methodologies for identifying free radicals and can provide valuable information about structural and chemical properties for especially stable radical species formed in drugs after X-ray exposure [4]. In this study, physicochemical properties and formed radicals of X-ray exposed anti-diabetics (metformin HCl, pioglitazone HCl) and proton pump inhibitors (PPI) (lansoprazole, pantoprazole sesquihydrate) were investigated before and after X-ray irradiation. 2. MATERIALS AND METHODS X-ray irradiation doses were selected based on the doses used in X-ray machines for security purposes (0.12 mGy from one pass) [1]. Doses were determined from the reference dose for the investigation of X-ray effects on pharmaceuticals. X- ray irradiation doses are 0.24 mGy and 1.2 mGy which were equivalent to 2 and 10 passes, respectively and 58 mGy which was chosen as an extremely high dose. Organoleptic properties (color, odor, and appearance) were investigated before and after X- ray exposure. The spectroscopic features of radiolytic intermediates produced in X-ray irradiated (o.24; 1.2; and 58 mGy) and non- irradiated drug samples were investigated after 1 hour at room temperature by using ESR spectroscopy. The utilization of quantitative electron paramagnetic resonance spectrometry has been increasing with increasing rate in the chemical, physical, biological, and medical sciences. This is because of its high sensitivity and broad dynamic range property, and its ability to be calibrated with any convenient paramagnetic materials [5]. This technique is also accepted to be high sensitivite when it is compared with other conventional techniques [6]. ESR studies were performed by using Bruker EMX 113X-Band ESR spectrometer