Figure 2: The UV-vis absorption spectra of HSA in the absence and presence of 5-iodo-4-thio-2'- deoxyuridine. Curve B, the absorption spectrum of 5-iodo- 4-thio-2'-deoxyuridine only; curve D-M, the difference absorption spectrum between 5-iodo-4-thio-2'-deoxyuridin-HSA and 5-iodo-4-thio -2'-deoxyuridin, n (HSA): n (5-iodo-4-thio-2'-deoxyuridin)=1: 2, 4, 6, 8, 10, 12, 14, 16, 18, 20.