title: Desktop near-field thermal-lens microscope for thermo-optical detection in microfluidics.
abstract: A new compact near-field desktop-sized diode laser thermal-lens microscope for analysis in microfluidics was proposed. A novel beam-alignment and detection systems provided high signal stability and, along with reduced number of optical elements rendered the instrument portable. The detection of nonfluorescent model species (Fe(II)-bathophenanthroline chelate) in water showed good linearity in the range of 5 × 10(-9) to 1 × 10(-4) M, and the limit of detection was 3.5 × 10(-9) M, which corresponded to 3.5 × 10(-7) absorbance units and provided a 20-fold enhancement in sensitivity compared with existing schematic.
authors.affiliation: Applied Chemistry Department, The University of Tokyo, Tokyo, Japan.
authors.forename: Adelina
authors.initials: A
authors.lastname: Smirnova
authors.forename: Mikhail A
authors.initials: MA
authors.lastname: Proskurnin
authors.forename: Kazuma
authors.initials: K
authors.lastname: Mawatari
authors.forename: Takehiko
authors.initials: T
authors.lastname: Kitamori
mesh_terms: D004396:Coloring Agents / Q000737:chemistry; D004867:Equipment Design; D054023:Lasers, Semiconductor; D046210:Microfluidic Analytical Techniques / Q000295:instrumentation* / Q000379:methods*; D008853:Microscopy / Q000295:instrumentation*; D008956:Models, Chemical; D013057:Spectrum Analysis / Q000295:instrumentation*
chemical_list: D004396:Coloring Agents