Dual-laser, differential fluorescence correction method for reducing cellular background autofluorescence
Article first published online: 30 MAR 2005
Copyright © 1986 Wiley-Liss, Inc.
Volume 7, Issue 6, pages 566–574, November 1986
How to Cite
Steinkamp, J. A. and Stewart, C. C. (1986), Dual-laser, differential fluorescence correction method for reducing cellular background autofluorescence. Cytometry, 7: 566–574. doi: 10.1002/cyto.990070611
- Issue published online: 16 JUN 2005
- Article first published online: 30 MAR 2005
- Manuscript Accepted: 10 JUL 1986
- Manuscript Received: 12 MAY 1986
- Autofluorescence correction;
- dual laser excitation;
- differential amplifier;
- flow cytometry;
- immunofluorescence measurements
A method has been developed for reducing the intrinsic autofluorescence background component in cells labeled with fluorescent antibodies, thus permitting low levels of antibody-binding on highly autofluorescent cells to be quantified. The method is based on the broad autofluorescent excitation spectra compared to the well-defined spectra of the fluorescent label. Two laser wavelengths were used, one optimally to excite the fluorescent label plus autofluorescence and the second to excite only the autofluorescence. Two fluorescence measurements were made in the same wavelength region and the signals were subtracted on a cell-by-cell basis using a difference amplifier to zero the autofluorescence and amplify the signal from the fluorescent label. Test results on unlabeled autofluorescent macrophages showed that the autofluorescence component was reduced by balancing the signal inputs to the difference amplifier. When labeled macrophages were analyzed, the autofluorescence was reduced and the fluorescent-labeled antibody-binding component was amplified. The method was also able to resolve labeled lymphocytes from unlabeled autofluorescent macrophages.