title: Poly(dimethylsiloxane)-based protein preconcentration using a nanogap generated by junction gap breakdown.
abstract: Simple and efficient sample concentration tools are the key to the application of proteomics in a biological system. In this paper, we developed a method to realize a nanofluidic preconcentrator on a poly(dimethylsiloxane) (PDMS)-based microfluidic channel. The originality of our preconcentration device is the simple nanogap formation using the junction gap breakdown phenomenon between two PDMS microchannels, without using any photolithography and etching techniques. From the dc current measurement, we confirm that the nanogap formed between two microchannel junctions with approximately 80 nm depth. Using this device, we achieve the concentration volume of beta-phycoerythrin protein as high as 70 pL, which is 120-fold larger than that from our previous reports, with a concentration factor as high as 10(4) within 1 h. Also we show the availability of protein preconcentration under several different buffers (phosphate, acetate) at several different pH values (pH 5 to pH 9).
authors.affiliation: Department of Electrical Engineering and Computer Science, and Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
authors.forename: Jeong Hoon
authors.initials: JH
authors.lastname: Lee
authors.forename: Seok
authors.initials: S
authors.lastname: Chung
authors.forename: Sung Jae
authors.initials: SJ
authors.lastname: Kim
authors.forename: Jongyoon
authors.initials: J
authors.lastname: Han
mesh_terms: D004129:Dimethylpolysiloxanes / Q000737:chemistry*; D004583:Electrons; D006863:Hydrogen-Ion Concentration; D049329:Nanostructures; D010799:Phycoerythrin / Q000737:chemistry* / Q000302:isolation & purification
chemical_list: D004129:Dimethylpolysiloxanes; D010799:Phycoerythrin