Method and device for determining predetermined properties of target particles of a sample medium

US6137584A · kind A · utility

Assignees

• Max-Planck-Gesellschaft · DE
• EVOTEC BIOSYSTEMS GMBH · DE

Inventors

• Claus Seidel · Göttingen, DE
• Leif Brand · Göttingen, DE
• Rolf W. Günther · Hersbruck, DE

Key dates

• Filing date: May 14, 1999
• Grant date: Oct 24, 2000
• Expiry date: May 14, 2019

Classification

• Technology area (CPC G): Physics
• CPC primary: G01N2015/0222
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A method and device are disclosed for expanding the field of application of florescent correlation spectroscopy. The device has a confocal optical structure, a pulsed laser for excitation and components for detection and evaluation of measuring signals for time-correlated single photon counting. The data is registered in such a way that for each detected photon, detection time is recorded in microseconds while fluorescence delay time is recorded in nanoseconds. The information on each detected photon is used to assign parameters determined by time-correlated single photon counting to each detected photon and to create correlation functions from the determined parameters arising therefrom. Correlation functions of parameters or selective correlation functions, e.g. for fluorescence burning life, are thus obtained. The method and the device can also be used to detect individual molecules and to calculate correlation functions only for those signal segments which are assigned to the individually existing particles, thereby improving the signal-to-noise ratio in extremely diluted solutions.