Quantitative analysis of glycosaminoglycans, chondroitin/dermatan sulfates, hyaluronic acid, heparan sulfate and keratan sulfate by LC-ESI-MS/MS

For simultaneous quantitative analysis of glycosaminoglycans (GAGs), we developed a method using LC-electrospray ionization-tandem MS (LC-ESI-MS/MS) with a selected reaction monitoring (SRM) mode. For the first time, we demonstrated the simultaneous quantification of a total of 17 variously sulfated disaccharides of 4 GAG classes (8 chondroitin/dermatan sulfates, 1 hyaluronic acid, 6 heparan sulfate and 2 keratan sulfate) with a sensitivity of less than 0.5 pmol within 18 min using this method. By one-shot analysis of GAGs with our MS/MS method, we showed the differences in the composition of GAG classes and the sulfation patterns between the porcine articular cartilage and yellow ligament. In addition to the internal disaccharides described above, some saccharides derived from the nonreducing terminal were also simultaneously detected. The simultaneous quantification of both internal and nonreducing terminal saccharides could be useful to estimate the chain length of GAGs. This method would help establish comprehensive GAGomic analysis of biological tissues.