(179d) Hydrodynamic Interactions in Semidilute DNA Solutions in Microfluidic Flow

Understanding the dynamics of DNA solutions in simple and complex microfluidic channels is critical for devices that manipulate DNA molecules for analysis and chemical reaction applications. Recent simulation and experimental work have shown that hydrodynamic interactions between DNA segments can lead to DNA migration towards the channel center, thus enabling passive separation of DNA molecules by flow. In this work, we investigate the dynamics of DNA chains in channels of dimensions comparable to the chain radius of gyration by employing the lattice Boltzmann method (LBM). Prior comparisons to Brownian dynamics and experiments have shown that LBM is able to capture DNA relaxation and diffusion in confined systems. The present work investigates how inter-chain interactions affect the chain conformation and chain migration by varying the molecule concentration up to the dilute-semidilute crossover. We also extend this approach to investigate the thermal-induced migration of DNA solutions under a temperature gradient in the microchannel and compare the results to experiments.