KARAKTERISTIK RADIOFARMAKA 99mTc-GLUTATION

ABSTRAKKARAKTERISTIK RADIOFARMAKA 99mTc-GLUTATION. Senyawa bertandateknesium-99m-glutation (99mTc-GSH) merupakan radiofarmaka yang digunakan dalam bidangkedokteran nuklir untuk diagnosis kanker dengan metode pencitraan. Karakteristik fisiko-kimiadan biologis suatu radiofarmaka memegang peranan penting dalam penyebaran sertapenimbunannya di dalam tubuh. Oleh karena itu, untuk menjamin keberhasilan penggunaanradiofarmaka perlu dilakukan pengujian sifat fisiko-kimia dan biologisnya. Pengujian kemurnianradiokimia dilakukan dengan kromatografi lapis tipis (TLC-SG) menggunakan aseton kering danNaCL 0,9% sebagai fase gerak. Muatan 99mTc-GSH ditentukan dengan metode elektroforesisdan lipofilisitasnya (P) diketahui dengan menentukan koefisien partisinya dalam pelarut organikair.Ikatan protein plasma ditentukan secara in-vitro dengan metode pengendapanmenggunakan larutan asam trikloro asetat (TCA) 5%. Di samping itu, dilakukan juga pengujianpengaruh besarnya radioaktivitas 99mTc terhadap stabilitas 99mTc-GSH serta stabilitas di dalamplasma secara in-vitro. Dari hasil percobaan diperoleh bahwa radiofarmaka 99mTc-GSHmempunyai kemurnian radiokimia 99,08 ± 0,26%; tidak bermuatan listrik (netral); lipofilisitas =0,03 ± 0,002; ikatan protein plasma sebesar 30,31 ± 0,04%. Penggunaan larutan Na99mTcO4sampai mencapai konsentrasi radioaktivitas 21 mCi/2 mL menghasilkan radiofarmaka 99mTc-GSH yang tetap stabil hingga 5 jam dengan kemurnian radiokimia ≥ 95%. Uji stabilitas 99mTc-GSH dalam plasma secara in-vitro menunjukkan bahwa kemurnian radiokimia menurun dengancepat pada penyimpanan satu jam pertama, yaitu sebesar 63,41± 4,86% dan kemurnianradiokimia antara 55 - 57 % bertahan hingga 5 jam penyimpanan.Kata kunci : karakteristik, radiofarmaka, 99mTc, glutation, kankerABSTRACTCHARACTERISTIC OF 99mTc-GLUTATHIONE RADIOPHARMACEUTICAL.Technetium-99m glutathione labelled compound is a radiopharmaceutical which is used innuclear medicine for cancer diagnoses by imaging method. The distribution and accumulation ofradiopharmaceutical in the body depend on its physicochemical and biological characteristic.Therefore, the determination of its characteristic was carried out in order to assure the succesfulutilization of this radiopharmaceutical. The radiochemical purity was determined with thin layerchromatography (TLC-SG) using dried aceton and 0.9% of NaCl solution as a mobile phase.The charge of 99mTc-GSH was tested by electrophoresis method and its lipophilicity (P) wasobtained by determination of octanol-water partition. The plasma binding protein of thisradiopharmaceutical was in-vitro investigated with precipitation method using 5% of trichloroacetic acid solution. Beside that, studies on the effect of 99mTc radioactivity to the stability of99mTc-GSH and its stability in plasma has been in-vitro carried out. From the experiment it wasobtained that 99mTc-GSH has 99.08 ± 0.26% of radiochemical purity; neutral (no charge); thelipophilicity (P) = 0.03 ± 0.002; the plasma binding protein of 30.31 ± 0.04%. Utilization of 99mTcradioactivity concentration up to 21 mCi/2 mL resulted 99mTc-GSH radiopharmaceutical whichwas remained stable up to 5 hours with ≥ 95% of radiochemical purity. In-vitro stability test of99mTc-GSH in plasma indicated that in the first hour of storage, the radiochemical puritydrastically decreased and until 5 hours of storage, its radiochemical purity did not changesignificantly, that was about 50%.Keywords: characteristic, radiopharmaceutical, 99mTc, glutathione, cance