Local measurement of liquid viscosity in optical tweezers

We present a modified method of measuring liquid viscosity in an optical tweezer system. The oscillating viscosity measurement was developed theoretically and then experimentally verified. The presented method enables quick measurement, does not require much space and the use of a camera enables other measurements, e.g. in the field of molecular biology, to be carried out in the same sample. Measurement of liquid viscosity using the presented method is possible for viscosities up to 2,5 mPa*s.