Construction of DNA-templated nanoparticle assemblies using click DNA ligation

We report a simple and versatile strategy for the construction of DNA-templated nanoparticle (NP) assemblies using click DNA ligation. Diels-Alder cycloaddition reaction of maleic acid and sorbic acid is used for click DNA ligation. Sorbic acid-prelabelled DNA nanowires with micron-scale length were synthesized and acted as templates for the construction of NP assemblies. Au NPs were orderly assembled onto the DNA nanowires using the click DNA ligation to form DNA-templated Au NP chains. Furthermore, DNA-templated CdTe quantum dot (QD) chains were synthesized using the method and characterized by confocal fluorescence microscopy (CFM). The DNA-templated CdTe QD chains were functionalized with cell-binding aptamer as the recognition element. The aptamer-functionalized CdTe QD chains, acting as a novel linear-shaped cellular probe, could be used for cancer cell imaging. Target cells could be rapidly and easily distinguished from a mixture of multiple cells using the cellular probe. The click DNA ligation method offers a convenient and efficient way to synthesize DNA-templated NP assemblies, and may become a powerful tool in other DNA-based studies.