
Preparing Samples
Voyager
™
Biospectrometry
™
Workstation User’s Guide 3-9
3
CHCA for thin layer
application
Use for peptides <3,000 Da.
Matrix concentration 20 mg/ml
Final sample concentration Up to 0.1 pmol/µl
Materials and solvents • Pure nitrocellulose (for example, Bio-Rad
Laboratories Trans-Blot
®
162-0146)
• Acetone
• Isopropanol
Preparation
1
1. Dissolve nitrocellulose to a concentration of
20 mg/ml in acetone by vortexing for 15 minutes.
2. Add isopropanol at a ratio of 1:1.
3. Add
α
-cyano-4-hydroxycinnamic acid to a final
concentration of 20 mg/ml.
Air dry sample plate after loading matrix. Dry with
gentle air flow after adding sample.
NOTE: If the dry matrix is a mustard-yellow color instead of bright yellow, it may
contain impurities. To recrystallize (purify), dissolve the
α
-cyano matrix in warm
ethanol. Filter and add about two volumes of deionized water. Let stand in the
refrigerator overnight. Filter, then wash the precipitate with cold water. This
procedure is not optimized for yield.
Crystals Rounded (see Figure 3-1 on page 3-34)
Stability Prepare weekly.
1. Other special sample preparation techniques are described in Shevchenko, A., M. Wilm, O. Vorm, M.
Mann,
Anal. Chem.,
1996, 68, 850–858.
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