Microfluidic System for Detection of α-Thalassemia-1 Deletion Using Saliva Samples

Abstract

This current study presents a new miniature, integrated system capable of rapid detection of genetic deletion from saliva samples. Several critical modules including a genomic DNA (gDNA) extraction module, a polymerase chain reaction (PCR) module, and an external optical detection module are integrated into the system. Silica-modified magnetic beads are first incubated with saliva in an extraction chamber with a cell lysis solution. This is followed by the collection of released gDNA onto the surface of the microbeads, which is then further purified and concentrated utilizing a magnetic field generated by an on-chip array of microcoils. Then, genetic deletion of human genes can be specifically amplified by the on-chip PCR module and is immediately detected using the optical detection module. Experimental results show that high-quality gDNA with an average concentration of 50.45 ng/microL can be extracted from 100 microL of saliva. The detection of a mutated alpha-globin gene associated with alpha-thalassemia-1 of southeast Asian (SEA)-type deletion can be completed within less than 1 h. Moreover, the detection limit of the system is found to be 12.00 pg/microL with a high sensitivity up to 90%. Consequently, the proposed saliva-based miniature system can provide a powerful platform for rapid DNA extraction and detection of genetic diseases.

Fast detection of genetic information by an optimized PCR in an interchangeable chip

“…DNA purification is performed before Electronic supplementary material The online version of this article (doi:10.1007/s10544-011-9595-6) contains supplementary material, which is available to authorized users. loading onto the chip or as an additional step incorporated into microfluidics design (Chen et al 2007;Lien et al 2009;Ng et al 2004). There are some reports of successful amplification directly from blood or saliva (Park et al 2008).…”

A suction-type, pneumatic microfluidic device for liquid transport and mixing

“…Recently, pneumatic-driven micro-pumps with the incorporation of micro-valves have been demonstrated to be one of the most popular microfluidic devices for LOC applications such as cell culture (Huang and Lee 2007), disease detection (Lien et al 2009), and synthesis of nanoparticles (Weng et al 2009). Sample fluids can be transported and blocked in the microfluidic channels by utilizing the pneumatic micro-pumps/valves driven by a positive pressure (Huang et al 2006).…”

Mesoporous hybrid membrane based label free electrochemical immunoassay

“…Gold nanoparticle provides distinct optical properties and was applied to detect Salmonella genomic DNA by naked-eye colorimetric platform [6]. Microfabrication contributes to generate an advance and suitable structure of microfludic system for convenient detection of u-Thalassemia-l deletion by using saliva samples [7].…”