Dissolving peptides

1. Start with a small amount of peptide before dissolving everything.

2. Most peptide can be dissolved in aqueous solution. Dissolve the peptide initially in water.

3. Count number of acidic residue (Asp (D), Glu (E)) and basic residues (Arg (R), Lys (K), His (H)) in the peptide.

4. If the peptide is acidic (negative charge), add NH4OH and dilute.

5. If the peptide is basic (positive charge), add acetic acid and dilute.

6. If the peptide is neutral, organic solvents such as DMSO, acetonitrile, methanol or isopropanol may be added.

7. Denaturants such as urea or guanidinium-HCl may be required.

8. Sonication may help.