In vitro incorporation studies of 99m Tc–alendronate sodium at different bone cell lines Evren Gundogdu • Derya Ilem-Ozdemir • Makbule Asikoglu Received: 21 June 2013 / Published online: 19 November 2013 Ó Akade ´miai Kiado ´, Budapest, Hungary 2013 Abstract Bisphosphonates can be labeled with Techne- tium-99m ( 99m Tc) and are used for bone imaging because of their good localization in the skeleton and rapid clearance from soft tissues. Over the last decades bone scintigraphy has been used extensively in the evaluation of oncological patients to provide information about the sites of bone lesions, their prognosis and the effectiveness of therapy by showing the sequential changes in tracer uptake. Since the lesion visualization and lesion/bone ratio are important utilities for a bone scanning radio- pharmaceutic; in this study incorporation of 99m Tc labeled alendronate sodium ( 99m Tc–ALD) was evaluated in U 2 OS (human bone osteosarcoma) and NCI-H209 (human bone carcinoma) cell lines. ALD was directly labeled by 99m Tc, radiochemical purity and stability of the complex were analyzed by radioactive thin layer chromatography and radioactive high performance liquid chromatography studies. For cell incorporation study, NCI-H209 and U 2 OS cell lines were used with standard cell culture methods. The six well plates were used for all experi- ments and the integrity of each cell monolayer was checked by measuring its transepithelial electrical resis- tance (TEER) with an epithelial voltammeter. Results confirmed that ALD was successfully radiolabeled with 99m Tc. 99m Tc–ALD incorporated with NCI-H209 and U 2 OS cells. The uptake percentages of 99m Tc–ALD in NCI-H209 and U 2 OS cell lines were found significantly different. Since 99m Tc–ALD highly uptake in cancer cell line, the results demonstrated that radiolabeled ALD may be a promising agent for bone cancer diagnosis. Keywords Bone scintigraphy  Bone cancer diagnosis  99m Tc–alendronate sodium  Cell incorporation study  Human bone carcinoma  Human bone osteosarcoma Introduction Radiopharmaceuticals are drugs which contain radionu- clide for the diagnosis or treatment of a disease. Radio- pharmaceuticals employed for diagnostic purposes, produce a physical signal (emission of gamma rays etc.) that can be detected by a camera. Most of the radiophar- maceuticals are administered systemically and the body distribution provided by scintigraphic studies [1]. Because of its favorable gamma energy and lack of particulate radiation, 99m Tc is employed for about 85 % of single- photon imaging procedures performed in nuclear medicine [2]. Virtually all radiopharmaceuticals employed for bone scintigraphy exhibit a similar pattern of distribution, characterized by accumulation in the bone linked to deposition of the mineral component. Bone scintigraphy with radiopharmaceuticals became one of the most fre- quently performed diagnostic nuclear medicine procedures. Bone scintigraphy is a highly sensitive method for dem- onstrating disease such as cancer in bone, often providing earlier diagnosis or demonstrating more lesions than are found by conventional radiological methods. For an ideal bone imaging agent three important properties are pro- posed; a high ratio of lesion/bone uptake, low background activity in soft tissue and rapid clearance from the body [3]. E. Gundogdu Department of Biopharmaceutics and Pharmacokinetics, Faculty of Pharmacy, Ege University, Bornova, Izmir, Turkey D. Ilem-Ozdemir (&)  M. Asikoglu Department of Radiopharmacy, Faculty of Pharmacy, Ege University, Bornova, Izmir, Turkey e-mail: deryailem@gmail.com 123 J Radioanal Nucl Chem (2014) 299:1255–1260 DOI 10.1007/s10967-013-2833-z