The Preparation of Microfluidic Architecture with Monolithic Materials Using a Dual Porous Silica Structure

A microfluidic device (MD) has been developed which features a porous silica (PS) monolithic disk synthesized from tetramethyl orthosilicate (TMOS), incorporated into the device post-fabrication and sealed in place with a second PS monolithic layer, synthesized from potassium silicate. This dual porous silica (DPS) structure provides a pathway for sample introduction to the microfluidic device and offers an ideal platform for solid phase extraction (SPE) methodologies which can be rapidly and efficiently integrated into a chip-based format. All silica disk manufacture and functionalization was carried out in batch to provide a readily scalable method of production. Application of this design for processing samples was demonstrated using two alternative nucleic acid purification chemistries, yielding polymerase chain reaction (PCR)-amplifiable DNA extracted from 150 μL of human urine in less than 35 mins. It is proposed that this DPS system could be further developed for a diverse range of chip-based SPE applications, providing an interface facilitating sample delivery and enabling SPE on-chip. Furthermore, to the author's knowledge it is the first reporting of two different types of porous silica amalgamated in a single microfluidic device. This article is protected by copyright. All rights reserved