Fig. 1

Schematic diagram of sequential releases and analyses of N-linked and O-linked glycans via chemoenzymatic method. a Immobilize glycoproteins on solid support. b Modify sialic acids; c release N-glycans using PNGase F; d label N-glycans by the isobaric tags such as QUANTITY via reductive amination; e release O-glycans by β-elimination. The released O-glycans are purified using C18 cartridge and N-glycans are purified using Carbograph SPE column