Lipid A lipid A 14 article 12 Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization 8 chemistry 8 mass spectrometry 8 Lipopolysaccharides 6 O Antigens 6 O antigen 6 bacterium lipopolysaccharide 6 matrix assisted laser desorption ionization time of flight mass spectrometry 6 methodology 6 nonhuman 6 Amines 4 Bacteria 4 Core oligosaccharide 4 Dansyl Compounds 4 Horseradish Peroxidase 4 Hydrazines 4 Mass spectrometry 4 Salmonella enterica 4 amine 4 bacterial strain 4 carbohydrate analysis 4 controlled study 4 dansyl chloride 4 dansyl hydrazine 4 gene expression 4 horseradish peroxidase 4 hydrazine 4