title: Novel fluorescence detection technique for non-contact temperature sensing in microchip PCR.
abstract: DNA amplification using Polymerase Chain Reaction (PCR) in a small volume is used in Lab-on-a-chip systems involving DNA manipulation. For few microliters of volume of liquid, it becomes difficult to measure and monitor the thermal profile accurately and reproducibly, which is an essential requirement for successful amplification. Conventional temperature sensors are either not biocompatible or too large and hence positioned away from the liquid leading to calibration errors. In this work we present a fluorescence based detection technique that is completely biocompatible and measures directly the liquid temperature. PCR is demonstrated in a 3 muL silicon-glass microfabricated device using non-contact induction heating whose temperature is controlled using fluorescence feedback from SYBR green I dye molecules intercalated within sensor DNA. The performance is compared with temperature feedback using a thermocouple sensor. Melting curve followed by gel electrophoresis is used to confirm product specificity after the PCR cycles.
authors.affiliation: Department of Physics, Indian Institute of Science, Bangalore-560012, India. sudipm@physics.iisc.ernet.in
authors.forename: Sudip
authors.initials: S
authors.lastname: Mondal
authors.forename: V
authors.initials: V
authors.lastname: Venkataraman
mesh_terms: D010582:Bacteriophage lambda / Q000235:genetics; D001483:Base Sequence; D052160:Benzothiazoles; D017931:DNA Primers / Q000235:genetics; D004279:DNA, Viral / Q000737:chemistry / Q000235:genetics; D003959:Diamines; D005453:Fluorescence; D005456:Fluorescent Dyes; D046208:Microchip Analytical Procedures / Q000379:methods*; D020411:Oligonucleotide Array Sequence Analysis / Q000379:methods*; D009930:Organic Chemicals; D016133:Polymerase Chain Reaction / Q000379:methods*; D011804:Quinolines; D013696:Temperature
chemical_list: D052160:Benzothiazoles; D017931:DNA Primers; D004279:DNA, Viral; D003959:Diamines; D005456:Fluorescent Dyes; D009930:Organic Chemicals; D011804:Quinolines; C098022:SYBR Green I