Biopolym. Cell. 1989; 5(3):79-82.
Structure and Function of Biopolymers
Ethidium bromide binding to polyriboguanylic acid
1Babayan Yu. S.
  1. Yerevan State University, Department of Molecular Physics and Biophysics,
    Yerevan, USSR


The binding of ethidium bromide to polyriboguanylic acid has been investigated according to the character of changes in absorption spectra. The calculations have shown that the saturation stoichiometry at binding makes up one ethidium bromide molecule per 5 guanine bases with binding constant (5.2В±0.8) -104 M-1 in the presence of 0.1 M NaCl and at room temperature.


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