Fabrication of DNA purification microchip integrated with mesoporous matrix based on MEMS technology

Abstract

This paper presents a novel microfabricated DNA purification microfluidic chip with enhanced performance based on the principle of micro solid phase extraction. The microchip comprises a layer of mesoporous material as solid phase matrix which is fabricated on the internal wall of the channel of microfluidic chip by electrochemical etching Si in an electrolyte. The conditions of electrochemical etching and porosity of the mesoporous matrix have been investigated. The properties of mesoporous matrix have been characterized by scanning electron microscopy and by BET (Brunauer, Emmet, and Teller) nitrogen adsorption analysis. The pore size of the mesoporous matrix is in the range of 10-30 nm, and the surface area is about 300 m 2 /g. Compared with the microfluidic chips with micropillar array matrix or non-porous matrix, the microchip with mesoporous matrix is able to extract enough polymerase chain reaction-amplifiable DNA from cultures of rat mesenchymal stem cells in 20 min. This highly efficient, effortless, and flexible technology can be used as a lab-on-a-chip component for initial biologic sample preparation.

Multibody interactions of actuated magnetic particles used as fluid drivers in microchannels

“…Systems based on capillary or electro kinetic flows have a strong dependence on the chemical properties of the sample (Vanderhoeven et al 2005;Laser and Santiago 2004). In fact, a fluid actuation system for high-surface-area elements should be fully integrated and suited for small samples of complex biological fluids (Chen et al 2007).…”

“…Devices for biochemical analysis therefore often contain elements with a large surface area to enhance binding capacity and allow parallel screening. For instance, porous DNA hybridization microarrays have become an effective form of screening technology and allow the analysis of hundreds to thousands of genes simultaneously (Chen et al 2007;Grasso et al 2006). A concern in these high-surface area systems is the limited accessibility of the reactive surfaces for the fluid and analyte, which slows down the effective reaction rate (Vanderhoeven et al 2005;Yuen et al 2003).…”