title: Integration of Multiplexed Microfluidic Electrokinetic Concentrators with a Morpholino Microarray via Reversible Surface Bonding for Enhanced DNA Hybridization.
abstract: We describe a microfluidic concentration device to accelerate the surface hybridization reaction between DNA and morpholinos (MOs) for enhanced detection. The microfluidic concentrator comprises a single polydimethylsiloxane (PDMS) microchannel onto which an ion-selective layer of conductive polymer poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (
  PSS) was directly printed and then reversibly surface bonded onto a morpholino microarray for hybridization. Using this electrokinetic trapping concentrator, we could achieve a maximum concentration factor of ∼800 for DNA and a limit of detection of 10 nM within 15 min. In terms of the detection speed, it enabled faster hybridization by around 10-fold when compared to conventional diffusion-based hybridization. A significant advantage of our approach is that the fabrication of the microfluidic concentrator is completely decoupled from the microarray; by eliminating the need to deposit an ion-selective layer on the microarray surface prior to device integration, interfacing between both modules, the PDMS chip for electrokinetic concentration and the substrate for DNA sensing are easier and applicable to any microarray platform. Furthermore, this fabrication strategy facilitates a multiplexing of concentrators. We have demonstrated the proof-of-concept for multiplexing by building a device with 5 parallel concentrators connected to a single inlet/outlet and applying it to parallel concentration and hybridization. Such device yielded similar concentration and hybridization efficiency compared to that of a single-channel device without adding any complexity to the fabrication and setup. These results demonstrate that our concentrator concept can be applied to the development of a highly multiplexed concentrator-enhanced microarray detection system for either genetic analysis or other diagnostic assays.
authors.affiliation: Division of Engineering, New York University Abu Dhabi , P.O. Box 129188 , Abu Dhabi, United Arab Emirates.
authors.forename: Diogo
authors.initials: D
authors.lastname: Martins
authors.affiliation: Division of Engineering, New York University Abu Dhabi , P.O. Box 129188 , Abu Dhabi, United Arab Emirates.|Department of Chemical and Biomolecular Engineering, New York University Tandon School of Engineering , Brooklyn, New York 11201, United States.
authors.forename: Xi
authors.initials: X
authors.lastname: Wei
authors.affiliation: Department of Chemical and Biomolecular Engineering, New York University Tandon School of Engineering , Brooklyn, New York 11201, United States.
authors.forename: Rastislav
authors.initials: R
authors.lastname: Levicky
authors.affiliation: Division of Engineering, New York University Abu Dhabi , P.O. Box 129188 , Abu Dhabi, United Arab Emirates.|Department of Chemical and Biomolecular Engineering, New York University Tandon School of Engineering , Brooklyn, New York 11201, United States.
authors.forename: Yong-Ak
authors.initials: YA
authors.lastname: Song
mesh_terms: D004247:DNA / Q000032:analysis* / Q000737:chemistry*; D007700:Kinetics; D046210:Microfluidic Analytical Techniques / Q000295:instrumentation*; D060172:Morpholinos / Q000737:chemistry*; D009693:Nucleic Acid Hybridization; D020411:Oligonucleotide Array Sequence Analysis / Q000295:instrumentation*; D013499:Surface Properties
chemical_list: D060172:Morpholinos; D004247:DNA