c 2 c 4 and c 5 2 c 8 2 odd electron c terminal ions were detected for z 1 z 4 and z 5 2 z 8 2 the mass difference between c 4 and c 5 2 together with z 4 and z 5 2 clearly shows the mass of the glycosylated asparagine residue g1f thus in contrast to the cid mass spectrum the etd generated mass spectrum provides precise identification of the n linked binding site following etd of the quadruply charged ion of m z 740 g2f full sequence information was obtained as shown in fig8 n terminal c ions even electron were detected for c 2 c 4 and c 5 2 c 8 2 odd electron c terminal ions were detected for z 1 z 4 and z 5 2 z 8 2 the mass difference between c 4 and c 5 2 together with z 4 and z 5 2 clearly shows the mass of the glycosylated asparagine residue g2f thus in contrast to the cid mass spectrum the etd generated mass spectrum provides precise identification of the n linked binding site following etd of the quadruply charged ion of m z 659 g0f full sequence information was obtained over the wider m z range from 200 2800 as shown in fig9 n terminal c ions even electron were detected for c 2 c 8 and c 5 2 c 8 2 odd electron c terminal ions were detected for z 1 z 8 and z 5 2 z 8 2 the mass difference between c 4 and c 5 together with z 4 and z 5 clearly shows the mass of the glycosylated asparagine residue g0f thus in contrast to the cid mass spectrum the etd generated mass.