Single- and countable-molecule detection of non-fluorescent molecules in liquid phase

Abstract A thermal lens microscope was applied to ultrasensitive detection of non-fluorescent molecule in liquid. The calibration curve showed good linearity in the 5.4–27 molecules region. The minimum number of molecules detected was 5.4 and the detection limit of Pb(II) octaethylporphyrin in benzene was 0.5 molecules. Our thermal lens microscope is a powerful tool for ultrasensitive detection of non-fluorescent molecules at the single-molecule level and offers a great potential for further applications.

[1]  Richard D. Snook,et al.  Thermal lens spectrometry. A review , 1995 .

[2]  G. Schubert,et al.  Magnetoconvection dynamos and the magnetic fields of Io and Ganymede , 1997 .

[3]  Takehiko Kitamori,et al.  Fast Slab Gel Electrophoretic Separation of DNA Fragments with a Short Migration Distance Using Thermal Lens Microscope , 1999 .

[4]  R N Zare,et al.  Probing individual molecules with confocal fluorescence microscopy. , 1994, Science.

[5]  R. Zare,et al.  Optical detection of single molecules. , 1997, Annual review of biophysics and biomolecular structure.

[6]  Takehiko Kitamori,et al.  Photothermal microscopy with excitation and probe beams coaxial under the microscope and its application to microparticle analysis , 1993 .

[7]  Takehiko Kitamori,et al.  Integration of Flow Injection Analysis and Zeptomole-Level Detection of the Fe(II)-o-Phenanthroline Complex , 1999 .

[8]  Takehiko Kitamori,et al.  Quantitation of Drug Concentration by Photo-Thermal Microscopy in a Renal Tubule of Fixed Kidney , 1997 .

[9]  E. Yeung,et al.  Single laser thermal lens detector for microbore liquid chromatography based on high-frequency modulation , 1986 .

[10]  Takehiko Kitamori,et al.  Individual detection of single-nanometer-sized particles in liquid by photothermal microscope. , 1998, Analytical chemistry.

[11]  Stephen E. Bialkowski,et al.  Photothermal spectroscopy methods for chemical analysis , 1995 .

[12]  Takehiko Kitamori,et al.  Sub-Attomole Molecule Detection in a Single Biological Cell in-vitro by Thermal Lens Microscopy , 1999 .