Replica multichannel polymer chips with a network of sacrificial channels sealed by adhesive printing method.
Replica microchips for capillary array electrophoresis containing 10 separation channels (50 microm width, 50 microm depth and 100 microm pitch) and a network of sacrificial channels (100 microm width and 50 microm depth) were successfully fabricated on a poly(methyl methacrylate) (PMMA) substrate by injection molding. The strategy involved development of moving mask deep X-ray lithography to fabricate an array of channels with inclined channel sidewalls. A slight inclination of channel sidewalls, which can not be fabricated by conventional deep X-ray lithography, is highly required to ensure the release of replicated polymer chips from a mold. Moreover, the sealing of molded PMMA multichannel chips with a PMMA cover film was achieved by a novel bonding technique involving adhesive printing and a network of sacrificial channels. An adhesive printing process enables us to precisely control the thickness of an adhesive layer, and a network of sacrificial channels makes it possible to remove air bubbles and an excess adhesive, which are crucial to achieving perfect sealing of replica PMMA chips with well-defined channel and injection structures. A CCD camera equipped with an image intensifier was used to simultaneously monitor electrophoretic separations in ten micro-channels with laser-induced fluorescence detection. High-speed and high-throughput separations of a 100 bp DNA ladder and phi X174 Hae III DNA restriction fragments have been demonstrated using a 10-channel PMMA chip. The current work establishes the feasibility of mass production of PMMA multichannel chips at a cost-effective basis.
Dang
F
F
Single-Molecule Bioanalysis Laboratory, National Institute of Advanced Industrial Science and Technology, Hayashi-cho 2217-14, Takamatsu 761-0395, Japan. fuquan-dang@aist.go.jp
Shinohara
S
S
Tabata
O
O
Yamaoka
Y
Y
Kurokawa
M
M
Shinohara
Y
Y
Ishikawa
M
M
Baba
Y
Y
D000269:Adhesives / Q000737:chemistry*; D010584:Bacteriophage phi X 174 / Q000737:chemistry; D004279:DNA, Viral / Q000737:chemistry; D019075:Electrophoresis, Capillary / Q000295:instrumentation* / Q000379:methods; D004867:Equipment Design; D005453:Fluorescence; D044085:Microfluidics / Q000295:instrumentation* / Q000379:methods; D008845:Microinjections / Q000295:instrumentation*; D019904:Polymethyl Methacrylate / Q000737:chemistry*; D011327:Printing / Q000295:instrumentation / Q000379:methods*; D012680:Sensitivity and Specificity; D013499:Surface Properties; D013997:Time Factors
D000269:Adhesives; D004279:DNA, Viral; D019904:Polymethyl Methacrylate