Effect of Chain Rigidity on the Crystallization of DNA-Directed Nanoparticle System

The DNA-directed nanoparticle (DNA-NP) system provides various applications in medical diagnosis, sensing, data storage, plasmonics, and photovoltaics. We studied the influence of chain rigidity on DNA-directed nanoparticle crystallization by molecular dynamics simulation. The results showed that the rigid and flexible chains grafted on nanoparticles can be used to design ordered supramolecular structure, but the mechanisms are different. The system with rigid DNA chains can induce nanoparticles' rearrangement into a body-centered cubic (BCC) lattice due to the DNA hybridization interactions. However, for the flexible chain system, the very low hybridization can even be ignored, yet the nanoparticles can still present BCC arrangement. For rigid chains, DNA binding interactions can induce BCC formation in a very narrow length range and are unfavorable to nanoparticle rearrangement for too long or short chains.