Optical Investigation of DNA Behaviour in Flow using Confocal Detection Incorporated with Fluorescence Correlation Spectroscopy (FCS).

Abstract

Investigation of the behavior of biopolymers in flow such as Deoxyribonucleic acid (DNA), is a critical challenge in engineering, polymer, and life sciences. In this study, we studied the rheological properties of DNA and flow characteristics in real-time. The velocity measurement was carried out using confocal detection incorporated with Fluorescence Correlation Spectroscopy (FCS). Optical experiments provided an understanding of the diffusion- and flow-dominated regimes for molecules treated in microfluidic channels and lab-on-chip devices in general. We found that the flow-dominated regime starts at a flow rate of 0.3 µl/min and the transitional regime falls into 0.02-0.3 µl/min flow rates. There are a few examples for the detection of DNA and different fragments in flow as such. It is therefore believed to provide valuable insights into the subject of flow dynamics of DNA.