
Preparing Samples
Voyager
™
Biospectrometry
™
Workstation User’s Guide 3-15
3
Synthetic polymer
matrices
Choice of matrix depends on the sample you are analyzing:
• Aromatic (for example, polystyrene)—Dithranol
(25 mg/ml) and 1 mg/ml silver trifluoroacetate (Ag TFA)
dissolved in tetrahydrofuran (THF)
• Polar—DHB (10 mg/ml) in deionized water
• Non-polar—Indole acetic acid (10 mg/ml) or DHB in THF,
dimethylformamide (DMF), or acetone
Matrix concentration ~0.1 M (10
-1
M)
Final sample concentration ~0.1 mM (10
-4
M)
Solvents Sample and matrix dependent. Choose solvents in
which polymer and matrix are soluble.
Preparation Follow the procedure in “Preparing matrix” on
page 3-5 and combine 1:1 sample:matrix.
See page 3-16 for application techniques.
Apply vacuum drying for non-volatile solvents
(water, DMF). Acetone and THF dry instantaneously.
Crystals No crystals visible.
If sample position looks glassy or shiny, it may
indicate sample concentration is too high.
Analyze polymer samples within one hour of loading
on the sample plate. Many polymer/matrix mixtures
are not stable once they are loaded.
Areas in which you see hot and cold spots are much
smaller with polar compounds than with non-polar
compounds.
Stability Prepare weekly. Store THF and acetone solutions in
tightly sealed vials.
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