Affinity capillary electrophoretic DNA separation using PEG-oligodeoxyribonucleotide block copolymers: Relationship between peak resolution and affinity strength

作者：Kanayama Naoki; Takarada Tohru^*; Kimura Ayumi; Shibata Hideaki; Maeda Mizuo

来源：Journal of Separation Science, 2008, 31(5): 837-844.

DOI：10.1002/jssc.200700521

• affinity capillary elecrrophoresis
• block copolymer
• DNA
• PEG
• SNPs

Capillary electrophoretic separation of chernically synthesized ssDNA and a single-base-substituted one (normal and mutant ssDNA, respectively) was demonstrated using a PEG-oligodeoxyribonucleotide block copolymer (PEG-b-ODN) as an affinity ligand. When the base sequence of PEG-b-ODN was designed to be complementary to part of normal ssDNA including the base-substituted site, the electrophoretic mobility of normal ssDNA significantly decreased whereas that of mutant ssDNA slightly changed. Resolution of the separation strongly depended on the ODN length of the copolymer, the capillary temperature, and the Mg2+ concentration in the running buffer, indicating that the retardation of migration of normal ssDNA was induced by the reversible hybridization with PEG-b-ODN. It was found that the dissociation constant (K-d) of the duplex between normal ssDNA and the affinity probe ODN should be smaller than 10(-6) M to achieve the good peak separation. In addition, we calculated the mobility of the complex (pc) between normal ssDNA and PEG-b-ODN using a two-state model.

• 出版日期2008-3