Article Electrons Glycosaminoglycans Sulfates Tandem Mass Spectrometry calibration chondroitin sulfate A hexasaccharide data analysis electron electron detachment dissociation electron detachment dissociation (EDD) fondaparinux glycosaminoglycan glycosaminoglycan (GAG) negative electron transfer dissociation negative electron transfer dissociation (NETD) process development sulfate tandem mass spectrometry tandem mass spectrometry (MS/MS) trifluoroacetic acid unclassified drug