>Mary Macris,
I've no experience, but for what it's worth, here's one reference:
Chemical Sequencing of Phosphorothioate Oligonucleotides Using
Matrix-Assisted Laser-etc. Polo, L.M., McCarley, T.D. and Limbach, P.A.
(1997) Anal. Chem. 69: 1107-1112.
You might also contact either Noubar Afeyan or Simin Maleknia, both of
Perseptive Biosystems who have published with others on this subject.
Sorry, I have only a preprint of this last one and can't help more.
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Gary M. Hathaway, Director
PPMAL - Protein/Peptide Micro Analytical Laboratory
California Institute of Technology
139-74, Division of Biology
Pasadena, CA 91125
http://www.cco.caltech.edu/~ppmal
email Gary: hathaway@caltech.edu
email facility: ppmal@caltech.edu
phone: lab (818) 395-6388 or office (818) 395-2769
FAX (818) 449-3414
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