Table 2. Multiple reaction monitoring (MRM) parameters of the 33-mer and the isotopically labelled *33-mer peptides.

Peptide	Precursor ions m/z (charge state)	Product ions1 m/z	Collision energy (V)	Retention time (min)
33-mer	979.0 (4+)21305.2 (3+)3	263.3 (y2)2	14	19.0
		488.9 (y4)3	26
		713.5 (y6)3	14
		973.5 (y8)3	12
*33-mer	987.0 (4+)21316.0 (3+)3	279.0 (y2)2	14	19.0
		510.3 (y4)3	26
		735.2 (y6)3	14
		996.0 (y8)3	12

¹Charge state: 1+.

²Precursor to product ion transitions were used as quantifier.

³Precursor to product ion transitions were used as qualifier.