Fluorescence correlation spectroscopy measurement based on fiber optics for biological materials

Abstract

A robust fluorescence correlation spectroscopy system called fiber-optic based fluorescence correlation spectroscopy (FB-FCS) was developed; this system enables the measurement of diffusion dynamics and concentration of fluorescent molecules based on the principle of fluorescence correlation spectroscopy without any mechanical adjustment of the experimental setup. The system consisted of fiber optics and a water-immersion objective lens. The hydrodynamic diameters and concentrations of organic fluorescent dyes and fluorescently labeled proteins were successfully measured. Because of the fiber-optic-based setup, the FB-FCS system is compact and inexpensive. We expect FB-FCS to be suitable for use in laboratories, medical diagnosis, and environmental measurements.