RE: Fluorescent Microbeads for Antigen Detection

Beavis, Andrew (abeavis@molecular.princeton.edu)
Mon, 16 Dec 96 09:10:00 PST

We have used several different fluorescent particles for detection of
various cell surface antigens. The polystyrene particles were labelled
with antibodies by passive adsorption, blocked with excess BSA and used
in a variety of immunofluorescence assays. The SKY BLUE particles (0.4 -
2.0 um) from Spherotech have a unique emission at 730 nm and permitted
six-colour immunofluorescence analysis (see Beavis and Pennline;
BioTechniques, vol 21 No. 3, pp 498). The SKY BLUE particles are excited
with either a 633 nm or 647 nm laser line and with the lower levels of
autofluorescence in the red region, may provide advantages for detection
of antigens expressed at low levels.

The TRANSFLUOSPHERES 488/720 from Molecular Probes can be excited at 488
nm with emission at 720 nm. Although there is significant emission around
525 nm through 625 nm, these particles can also be used in combination
with other 488-excited fluorochromes for multicolour analysis.

The LIGHT YELLOW fluorescent particles from Spherotech can be excited
with a UV laser ( 351-364 nm) with emission at around 400 nm. Despite
high levels of autofluorescence, these labelled particles were also
useful for cell surface antigen detection.

Regards

Andrew Beavis
Manager, Flow Cytometry Core Facility
Princeton University
Department of Molecular Biology
Lewis Thomas Laboratory
Washington Road
Princeton, NJ 08544

Tel. (609) 258 1695
e-mail. Abeavis@molecular.princeton.edu