Journal of Kerbala University , Vol. 13 No.4 Scientific . 2015 09 Primary screening for antitumor activity of Tetracycline- platinum (II) complex using Ultraviolet spectroscopy لثنائي معبلتين امعقذ اللورام لللمضادة لليت الفعاولي عن اتحري ال الكلينساي التترا وق البنفسجيت الشعت فستخذام طيف با Rajaa A. Hussein Huda A. Salih Department of Clinical & Laboratory Sciences-College of Pharmacy kufa University/ Al- Najaf / Iraq Raja.hussein@uokufa.edu.iq Abstract: In order to further clarify the molecular basis for the mechanism of action of the antitumor Pt(II) complexes, this work represent a study of the interaction of Pt(II) complex with calf thymus DNA and Human Serum Albumin (HAS) using UV-spectroscopy in vitro, this technique was used in order to gain quantitative information regarding the relative binding affinity of the platinum compounds for calf thymus DNA versus HAS. Spectra of solution of Pt(II) complex (0.07 mM ) at pH 7 was recorded at regular intervals in the absence and presence of calf thymus DNA (0.05mM) and HAS (0.16μM). The present study reveals that the UV spectrum of Cis-dicloro(tetracycline) platinum(II) complex [(Tet.)Pt Cl 2 ] at pH 7 pale yellow solution shows a maximum absorbance at 272nm and a shoulder peak at 364nm after 0.25h and 1 hr . These peaks are rapidly diminished with time due to rapid hydrolysis of the nephthacene rings to give a precipitate and loss of the pale yellow color of the solution after 24hrs. In contrast, the absorbance of platinum complex in the presence of calf thymus DNA and HAS is significantly altered compared to the control experiment. The shift in the maximum absorbance to 291nm and 290 (for complex with DNA and HAS respectively) from 272nm implies that the tetracycline ligand is in a different environment, consistent with formation of platinum – DNA and platinum-HAS complex. No precipitation occurred in solution, of platinum complex in the presence of calf thymus DNA and HSA at pH 7 over 24h. Key words: Antitumor activity. UV-visible spectroscopy, platinum (II) complex, in vitro خلصت: ال كه يع انخخراسببئ انثعقذ انبلح نراو خبرج اندسى انحضبدة نلوت ان انفعبن ع الونت انخحرج انذراست انحبن حض بىز انراىوئت انحبيض انه يع خسفبعهخ بDNA صم انبشر ان وانبىيHSA ف ات طخذاو حقبسخ ب ل شعت فىق تفسد انبUV—spectroscopy . عقذ انبلححهىل انت نفسد انشعت فىق انبفبش ط حى ق0.07mM) - PH 7 تىئبث انح اندس بىخىد) DNA ( 0.05mM و) HSA ( 0.16 mM ( تبوقبث يخخبن ب وخىدهبعذو و) 0.25 و1 و24 ف الشعتبش ط ق فضل ع) سبعت عقذف ان طت. اعطبست انقىئبث انحت نهدسفسد فىق انب)حبيحهىل اصفر شب( ىخذ انطىل انبص عت ايخص ق اعه 272 ىخذ انطىل انىيخر وكخف عب 364 ورىيخر بعذ يرب 1 , 0.25 سبعت, هحهىل نىى وفقذ انحهج انق اض ح ف راس وظهرورعقذ بعذ يرك ان حفككر انش ب24 ئبثع احذي اندسبشر يبعقذ ان حفبعم انعط , هت اخري خ سبعت . ي تى انحDNA اوHSA بص يى اليخص قصىل ازاحت فى بحع انق يىاقرا يهحىظب ف حغ272 عقذ بذو انف( ىيخرب DNA وHSA  ان) 290 و291 عقذ ي ان ف( ىيخرب عDNA وHSA  انخىان عهصىل حفبعمؤكذ ح ب ي) كذد حفكح ذ لت بحىئبث انح واندسعقذ انبلح انط بب وارحبب او حرسورح بعذ يربحركب ان نه24  سبعت ي انخفبعم. احيت:ث المفتكلما الت, يعقذاث انبلحفسد الشعت فىق انبفراو , طضبدة نلوت ان انفعبن , خبرج اندسى انحبئ انث