Hi Alex, We run ECFP off the 457nm line of our I-70 all the time but we do not use the 488nm at the same time. The maximum emission of ECFP is very close to 488nm so as I see it your choices are 1)Use the 514nm line of your primary laser to trigger your FSC (if you are not using an Enterprise laser). This way the 514nm line will not interfere with your collection of ECFP emission. Make sure to take out the 488nm filter in front of the FSC detector and replace it with something that will allow 514nm through but restrict as much as possible all wavelengths below 500nm where the emission of ECFP is strongest. 2)If you must use 488nm as your primary line put a 488nm restriction/blocking bandpass filter in front of your ECFP filter. You should buy a filter with as narrow a band around 488nm as possible so as not to lose to much of your ECFP signal some of which will be blocked by your 488nm restriction filter. Try to purchase a filter with an optical density (OD) of 5 from 483-493nm. I have used the 485/22 filter BD supplies with the instrument many times for ECFP collection but I would fear to great a loss of signal with a 488nm restriction filter in front of a 485/22. For system alignment I really like the 8 peak Spherotech beads. They give very nice signal when excited at 457nm and help you control for background. You should be able to easily see a difference in signal from the 1st and 2nd lowest intensity peaks. If you can not you either have a bad system alignment or you have high background from a laser line leaking light into your collection detector (i.e. 488nm leaking light into your ECFP detector). Good luck and let me know if I can help. Glenn ************************************************* Glenn Paradis MIT Flow Cytometry Core Facility E18-463 Massachusetts Institute of Technology Cambridge, MA 02139 (617)253-6454 lab (617)452-4132 office (617)253-3714 fax gap@mit.edu http://web.mit.edu/flowcytometry/www/ ************************************************* >Dear Flowers, > >On a FACSVantage SE: >Is anybody using the 457 line of a Spectrum 70 laser as a secondary >laser to excite ECFP ? >The primary laser is 488nm. >What is the best filter ? 470/15 , 485/22 >Do I need other filters (eg. blocking filters ?) >Which beads can be used for the laser alignment ? >It would be great if you could share your experiences with me. >Many thanks >Alex > > >-- >______________________________________ >Dr. Alexander Schmitz >FACS Core Facility >Department for Molecular Biology (MBI) C.F. Moellers Allee 130/3 >DK 8000 Århus >Denmark >axs@mb.au.dk >Tel: +45 8942 2676 >Tel: +45 2338 2429 Mobil >Fax +45 8916 6500 >______________________________________ -- Glenn ParadisReceived on Tue Mar 16 15:18:00 2004
This archive was generated by hypermail 2.1.8 : Wed Mar 17 2004 - 03:12:03 EST