Patent · US Expired

Fluorescent-particle analyzer with timing alignment for analog pulse subtraction of fluorescent pulses arising from different excitation locations

US5682038A · kind A · utility

132Cited by
4References
5Claims
0Family size

Assignee

Inventor

Key dates

Filing dateApr 6, 1995
Grant dateOct 28, 1997
Priority date
Expiry dateApr 6, 2015

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01N2015/1438
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A flow cytometry system includes a flow tube through which particles marked with different fluorochromes pass from a first location, illuminated by a red laser, to a second location, illuminated by a blue laser. A "red" photodetector is optically coupled to detect red fluorescence from both locations. "Yellow" and "green" photodetectors respectively detect yellow and green fluorescence from the second location, while a "scattered light" detector detects scattered light from the second location. During a sample run, the red photodetector can output pulses that correspond primarily to APC fluorochrome at the first location and to PerCP at the second location respectively. A delay device delays the APC pulse relative to the PerCP pulse so that the peaks can be scaled and subtracted in the analog electrical domain to remove APC/PerCP crosstalk. The delay is calibrated using a set of APC tagged cells. Each of these cells generates a red fluorescence electrical pulse while at the first location and a scattered light pulse while at the second location. The average time differential between these two pulses for the set of timing cells determines the target delay. This is compared with the …

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.