Aldrich has several different molecular weight PMMA beads, you will need to
know your MW in order to match what you need.  If possible, try to find a
hard copy realtime paper catalog, I found their website totally confusing
on this issue or call their technical services and ask them what the
equivalent is for your beads, bet they can cross reference it for you.  


Gayle Callis
MT,HT,HTL(ASCP)
Research Histopathology Supervisor
Veterinary Molecular Biology - Marsh Lab
Montana State University - Bozeman
19th and Lincoln St
Bozeman MT 59717-3610

406 994-6367 (lab with voice mail)
406 994-4303 (FAX)

email: gcallis@montana.edu