A Viscometric Chip for DNA Analysis

This paper describes a hybrid silicon/plastic chip which is used to analyze DNA samples without the need of fluorescence or surface functionalization. The viscosity and density of the solutions to be tested are measured using a vibrating silicon beam immersed in the fluid. The sensitivity of the chip with respect to DNA concentration and length is analyzed, yielding a limit of detection of 0.5 μg/μl. We show that the sensitivity of the chip is statistically significant for PCR end-point detection. State-of-the-art on-chip detection methods of DNA solutions need optical devices or specially designed reactions. With the viscometric method proposed in this paper, these drawbacks are avoided.