Analytical Sciences


Abstract − Analytical Sciences, 18(4), 391 (2002).

Interaction ofBis(ethylene)tin(bis(salicylidene)ethylenediamine) with DNA
Guo-Dong LIU,* Jian-Pei LIAO,** Yu-Zhi FANG,* Sha-Sheng HUANG,**Guo-Li SHENG,** and Ru-Qin YU**
*Department of Chemistry, East ChinaNormal University, Shanghai, 200062, P. R. China
**College of Chemistryand Chemical Engineering, Hunan University, Changsha, 410082, P. R.China
The fluorescence spectral characteristicsand interaction of bis(ethylene)tin(bis(salicylidene)ethylenediamine)[Et2Sn(salen)] with DNA are described. The polarity of thesolvent has a strong effect on the fluorescence characteristics ofEt2Sn(salen). Et2Sn(salen) bound to DNA showed amarked decrease in the fluorescence intensity with a bathochromic shift ofthe excitation and emission peaks. A hypochromism in the UV absorptionspectra was also observed. KI quenching and competitive binding to DNAbetween Et2Sn(salen) and ethidium bromide (EB) were studied inconnection with other experimental observations to show that theinteractive model between Et2Sn(salen) and DNA is anintercalative one. The pH and salt effect on the fluorescence propertieswas also investigated. The intrinsic binding constant was estimated to be1.071 x 105 mol L-1 in base pairs and the bindingsite number is 1.98, respectively. A linear relationship betweenF/F0 and the concentration of calf thymus DNAcovers 5.1 x 10-6 - 2.41 x 10-4 mol L-1,which can be utilized for determining traces of calf thymus DNA with adetection limit of 1.1 x 10-7 mol L-1 in basepairs.