2.;;Calculate the overall charge of the entire peptide according to the following table:
;
Contents
Assign value
Acidic amino acid
Asp (D), Glu (E), and the C-terminal -COOH.
-1
Basic amino acid
Arg (R), Lys (K), His (H), and the N-terminal -NH2
+1
Neutral amino acid
Gly (G), Ala (A), Leu (L), Ile (I), Val (V), Cys (C), Met (M), Thr (T), Ser (S), Phe (F), Tyr (Y), Trp (W), Pro (P), Asn (N), Gln (Q)
0
3.;;Recommended solution:
Overall charge of peptide
Details
Negative (lt;0)
1.;;Try to dissolve the peptide in water first. 2.;;If water fails, add NH4OH (lt;50 μL). 3.;;If the peptide still does not dissolve, add DMSO (50-100 μL) to solubilize the peptide.
Positive (gt;0)
1.;;Try to dissolve the peptide in water first. 2.;;If water fails, try dissolving the peptide in a 10%-30% acetic acid solution. 3.;;If the peptide still does not dissolve, try dissolving the peptide in a small amount of DMSO.
Zero (=0)
1.;;Try to dissolve the peptide in organic solvent (acetonitrile, methanol, etc.) first. 2.;;For very hydrophobic peptides, try dissolving the peptide in a small amount of DMSO, and then dilute the solution with water to the desired concentration.
