ScholarWorks@동국대학교

초록

In this study, we demonstrated that deoxyribonucleic acid (DNA) strands selectively bind to the surfaces of size-customized layered double hydroxide (LDH) particles, driven by a distinct size-matching interaction between the adsorbate and adsorbent. High-purity LDHs with specific particle sizes-LDH-S (small) and LDH-L (large)-were synthesized, and their DNA adsorption behaviors were systematically examined. The LDH-S exhibited a higher specific surface energy and zeta potential than LDH-L; whereas LDH-L possessed a well-ordered crystalline structure along the crystallographic ab-plane compared to LDH-S. According to the adsorption isotherm, the DNA strands were adsorbed onto the LDH surface in a multilayer manner. The mathematical fitting indicated that LDH-S had a higher adsorption capacity and less cooperative adsorption than LDH-L. Electrophoresis using size-specific ladder DNA confirmed that LDH adsorbed DNA in a size-selective manner; ladder DNA below 800 base pairs selectively adsorbed on LDH-S, while DNA above 800 base pairs preferred adsorption on LDH-L. The binding assay using large plasmid DNA corroborated that LDH-L displayed superior adsorption efficiency for large DNA fragments. The distinctive preference of LDH-L for large DNA might be due to cooperative interactions among DNA strands on expansive surfaces with periodic electrostatic interaction sites.

키워드