抄録
A novel spectroscopic measurement method has been established that enables to detect biomolecules in
a simple measurement configuration with a small absolute amount of sensing targets. A spectroscopic
cell with a sensing volume of sub-picoliter has been fabricated inside a glass optical fiber by use of near
ultraviolet (NUV) femtosecond laser pulses. By use of the cell with a combination of a halogen white
light source and a compact CCD spectrometer, spectroscopic measurements using localized surface
plasmon resonance (LSPR) were demonstrated. Absorption spectra using LSPR, which had the
absorption peak centered at 518 nm, were obtained when a solution of gold nanoparticles (GNPs) with a
diameter of 5‒10 nm was injected into the cell with a volume of 0.4 pL. An aggregation of GNPs caused
by biomolecules of L-cysteine was monitored by the change in the absorption spectra. The absorption
peak of LSPR decreased due to an injection of 7.5 mM of L-cysteine with the detection sensitivity of 3.0
× 10‒15 mol (3.6 × 10‒13 g).
