Biased reptation model with electroosmosis for DNA electrophoresis in microchannels with a sub-micron pillar array

A novel biased reptation model with electroosmosis (BRE) is proposed for a long-chain DNA electrophoresis separation mechanism in microchannels with a sub-micron pillar array. The BRE model incorporates effective electroosmosis into the classical biased reptation model (BRM). Initial investigation of the BRM with additional electroosmosis flow was conducted. In order to validate the proposed BRE model, the apparent electrophoretic mobilities of different sizes of long-chain DNA, T4 DNA and lambda DNA at different electric fields were measured in a microfabricated electrophoresis chip with an embedded sub-micron pillar array. The current-monitoring method was used to measure the electroosmotic mobility in the microfabricated electrophoresis chip. The proposed BRE model shows much better agreement with the experimental results compared to the classical BRM and the semi-empirical results based on the biased reptation with fluctuation (BRF). The average standard error between our proposed BRE model and experimental data is 8.13% without any fitting parameters, while the errors are 343.01% for the BRM and 17.54% for the BRF with one fitting parameter, respectively