Mass labels

A mass marker for labeling and detecting a biomolecule by mass spectrometry, which is represented by the following structure: X-L-M, wherein X is a mass-labeled moiety containing a group of formula (I) The ring units are aromatic or aliphatic and independently contain 0-3 double bonds between any two adjacent atoms; each Z is independently N, N (R1), C (R1), CO, CO (R1) C or R1; X is N, C or C (R1); each R1 is independently H, substituted or unsubstituted linear or branched C1-C6 alkyl, substituted or unsubstituted aliphatic A cyclic group, a substituted or unsubstituted aromatic group or a substituted or unsubstituted heterocyclic group; y is an integer of 0 to 10, L is a cleavable linker comprising an amide bond, and M is a mass normalized moiety.