Host: The Japan Society of Mechanical Engineers
Name : [in Japanese]
Date : September 13, 2020 - September 16, 2020
Recently, importance of nanomaterials has been drastically increased in various fields such as environment, medicine, and industry. Demand for detection and identification of them is, therefore, inevitably increasing. In this study, we developed a flow cytometer to achieve a real-time single-particle detection of nanoparticles. The developed cytometer contains two beam paths (one for excitation of nanoparticles flowing in a PDMS microchannel, and the other for reference light, whose frequency is slightly shifted by two acousto-optic modulators) to cause heterodyne interference. The scattering light from the particles is overlapped with the reference light and recorded via a lock-in amplifier. An increase of the sensitivity by the combination of the flow cytometry with the heterodyne interferometry was confirmed by 2-μm particles. Furthermore, it was shown that the cytometer can detect individual 10-nm gold particles while the detection limit of conventional cytometers are hundreds of nanometers.