title: Label-free detection of real-time DNA amplification using a nanofluidic diffraction grating.
abstract: Quantitative DNA amplification using fluorescence labeling has played an important role in the recent, rapid progress of basic medical and molecular biological research. Here we report a label-free detection of real-time DNA amplification using a nanofluidic diffraction grating. Our detection system observed intensity changes during DNA amplification of diffracted light derived from the passage of a laser beam through nanochannels embedded in a microchannel. Numerical simulations revealed that the diffracted light intensity change in the nanofluidic diffraction grating was attributed to the change of refractive index. We showed the first case reported to date for label-free detection of real-time DNA amplification, such as specific DNA sequences from tubercle bacilli (TB) and human papillomavirus (HPV). Since our developed system allows quantification of the initial concentration of amplified DNA molecules ranging from 1 fM to 1 pM, we expect that it will offer a new strategy for developing fundamental techniques of medical applications.
authors.affiliation: Department of Applied Chemistry, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan.|ImPACT Research Center for Advanced Nanobiodevices, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan.|Japan Science and Technology Agency (JST), PRESTO, 4-1-8 Honcho, Kawaguchi, Saitama 332-0012, Japan.
authors.forename: Takao
authors.initials: T
authors.lastname: Yasui
authors.affiliation: Department of Applied Chemistry, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan.
authors.forename: Kensuke
authors.initials: K
authors.lastname: Ogawa
authors.affiliation: Department of Applied Chemistry, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan.|ImPACT Research Center for Advanced Nanobiodevices, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan.
authors.forename: Noritada
authors.initials: N
authors.lastname: Kaji
authors.affiliation: Science for Life Laboratory, Department of Biochemistry and Biophysics, Stockholm University, Se-171 21 Solna, Sweden.
authors.forename: Mats
authors.initials: M
authors.lastname: Nilsson
authors.affiliation: Graduate School of Chemical Sciences and Engineering, Hokkaido University, Sapporo 060-8628, Japan.
authors.forename: Taiga
authors.initials: T
authors.lastname: Ajiri
authors.affiliation: ImPACT Research Center for Advanced Nanobiodevices, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan.|Division of Applied Chemistry, Faculty of Engineering, Hokkaido University, Sapporo 060-8628, Japan.
authors.forename: Manabu
authors.initials: M
authors.lastname: Tokeshi
authors.affiliation: National Institute for Materials Science, Tsukuba 305-0044, Japan.
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Horiike
authors.affiliation: Department of Applied Chemistry, Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan.|ImPACT Research Center for Advanced Nanobiodevices, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan.|Health Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Takamatsu 761-0395, Japan.
authors.forename: Yoshinobu
authors.initials: Y
authors.lastname: Baba
mesh_terms: D003199:Computer Systems; D004247:DNA / Q000032:analysis* / Q000235:genetics*; D056656:Lab-On-A-Chip Devices; D046210:Microfluidic Analytical Techniques / Q000295:instrumentation / Q000379:methods*; D036103:Nanotechnology; D021141:Nucleic Acid Amplification Techniques / Q000295:instrumentation / Q000379:methods*; D012031:Refractometry
chemical_list: D004247:DNA