Table 3.

Fragmentation efficiency of singly protonated α-MSH analogs and bioconjugates by MALDI MS/MS.

Compound	ISD	LID	CID
1; (4)	−	+ +; (+ + +)	+ + +; (+ +)
2; (5) Dau at N-terminus	−	+	+
3; (6) Dau at Lys	−	+ +; (+)	+ +; (+)

Symbols: −: no peptide sequence related fragments; +: the sequence coverage is 10–30%, where the relative intensity of the fragments is ≥5%; + +: the sequence coverage is 31–60%, where the relative intensity of the fragments is ≥5%; + + +: the sequence coverage is ≥61%, where the relative intensity of the fragments is ≥5%. Values for the compounds 4, and 6 are in brackets.