The effect of chlorophyllin on the binding of proflavine, doxorubicin, ethidium bromide, and berberine to DNA was studied by spectrophotometric titration. Titration data were analyzed using a multivariate curve resolution–alternating least squares method (MCR–ALS). Pure spectra of all absorbing species in the systems and their concentration profiles were obtained. Chlorophyllin was shown to form complexes with all studied ligands. The equilibrium constants for complexation of the ligands with chlorophyllin and DNA were obtained in binary (ligand–chlorophyllin and ligand–DNA) and ternary systems (ligand–chlorophyllin–DNA). The number of ligand molecules bound to DNA was observed to decrease in the presence of chlorophyllin. The main reason for this effect was heteroassociation because the calculated complexation constants of the ligands with DNA and chlorophyllin were similar. Theoretical isotherms of ligands binding to DNA in the ternary systems were compared to those obtained directly from decomposition data to test for the existence of other mechanisms for chlorophyllin competition. It was shown that consideration of only heteroassociation of the ligands with chlorophyllin (interceptor mechanism) was adequate to describe the experimental isotherms. Chlorophyllin did not exhibit protective properties in the studied ternary systems; consequently, chlorophyllin did not interact with DNA.

通过分光光度法滴定研究叶绿素对原黄素、多柔比星、溴化乙锭和小檗碱与 DNA 结合的影响。使用多元曲线分辨率-交替最小二乘法 (MCR-ALS) 分析滴定数据。获得了系统中所有吸收物质的纯光谱及其浓度分布。显示叶绿素与所有研究的配体形成复合物。在二元系统（配体-叶绿素和配体-DNA）和三元系统（配体-叶绿素-DNA）中获得了配体与叶绿素和DNA络合的平衡常数。在叶绿素存在的情况下，观察到与 DNA 结合的配体分子的数量减少。这种效应的主要原因是杂结合，因为计算出的配体与 DNA 和叶绿素的络合常数相似。将三元系统中与 DNA 结合的配体的理论等温线与直接从分解数据获得的等温线进行比较，以测试是否存在其他叶绿素竞争机制。结果表明，仅考虑配体与叶绿素的杂缔合（拦截机制）就足以描述实验等温线。叶绿素在所研究的三元系统中没有表现出保护特性；因此，叶绿素不与 DNA 相互作用。将三元系统中与 DNA 结合的配体的理论等温线与直接从分解数据获得的等温线进行比较，以测试是否存在其他叶绿素竞争机制。结果表明，仅考虑配体与叶绿素的杂缔合（拦截机制）就足以描述实验等温线。叶绿素在所研究的三元系统中没有表现出保护特性；因此，叶绿素不与 DNA 相互作用。将三元系统中与 DNA 结合的配体的理论等温线与直接从分解数据获得的等温线进行比较，以测试是否存在其他叶绿素竞争机制。结果表明，仅考虑配体与叶绿素的杂缔合（拦截机制）就足以描述实验等温线。叶绿素在所研究的三元系统中没有表现出保护特性；因此，叶绿素不与 DNA 相互作用。