Electrokinetically based approach for single-nucleotide polymorphism discrimination using a microfluidic device.
In this work, we describe and implement an electrokinetic approach for single-nucleotide polymorphism (SNP) discrimination using a PDMS/glass-based microfluidic chip. The technique takes advantage of precise control of the coupled thermal (Joule heating), shear (electroosmosis), and electrical (electrophoresis) energies present at an array of probes afforded by the application of external electrical potentials. Temperature controllers and embedded thermal devices are not required. The chips can be easily and inexpensively fabricated using standard microarray printing methods combined with soft-lithography patterned PDMS fluidics, making these systems easily adaptable to applications using higher density arrays. Extensive numerical simulations of the coupled flow and thermal properties and microscale thermometry experiments are described and used to characterize the in-channel conditions. It was found that optimal conditions for SNP detection occur at a lower temperature on-chip than for typical microarray experiments, thereby revealing the importance of the electrical and shear forces to the overall process. To demonstrate the clinical utility of the technique, the detection of single-base pair mutations in the survival motor neuron gene, associated with the childhood disease spinal muscular atrophy, is conducted.
Department of Mechanical and Industrial Engineering, University of Toronto, Toronto, Ontario, M5S 3G8, Canada.
David
D
Erickson
Xuezhu
X
Liu
Roberto
R
Venditti
Dongqing
D
Li
Ulrich J
UJ
Krull
D017362:Cyclic AMP Response Element-Binding Protein / Q000737:chemistry / Q000235:genetics*; D004252:DNA Mutational Analysis / Q000295:instrumentation* / Q000379:methods; D004563:Electrochemistry; D046210:Microfluidic Analytical Techniques / Q000295:instrumentation*; D009154:Mutation; D009419:Nerve Tissue Proteins / Q000737:chemistry / Q000235:genetics*; D020641:Polymorphism, Single Nucleotide / Q000235:genetics*; D016601:RNA-Binding Proteins / Q000737:chemistry / Q000235:genetics*; D055532:SMN Complex Proteins
D017362:Cyclic AMP Response Element-Binding Protein; D009419:Nerve Tissue Proteins; D016601:RNA-Binding Proteins; D055532:SMN Complex Proteins