Table 2. MSTFA-derivatized metabolites Metabolites MW-MSTFA [M-15]+ [M-117]+ Note Glyoxylate 175 160 43* [M-117]+ fragment is not Pyruvate 189 174 72* accurate. Lactate 234 219 117* 233 218 116 Alanine Glycine 291 276 174 [M-117]+ fragment is not Valine 261 246 144 accurate. Succinate 262 247 147 [M-117]+ fragment is not Fumarate 260 245 143 accurate. 321 306 204 Serine 263 248 146 Threonine The first and fifth carbon link to 273 258 158 form a cycle. α-ketoglutarate 319 304 302 Both fragments are not Aspartate 349 334 232 accurate. Glutamine 363 348 246 350 335 333 Malate Both fragments are not Citrate 480 465 463 accurate. References 1. Wahl SA, Dauner M, Wiechert W: New tools for mass isotopomer data evaluation in 13C flux analysis: Mass isotope correction, data consistency checking, and precursor relationships. 2004, 85(3):259-268. Biotechnol Bioeng
Table 2. MSTFA-derivatized metabolites Metabolites MW-MSTFA [M-15]+ [M-117]+ Note Glyoxylate 175 160 43* [M-117]+ fragment is not accurate. Pyruvate 189 174 72* Lactate 234 219 117* Alanine 233 218 116 Glycine 291 276 174 Valine 261 246 144 [M-117]+ fragment is not accurate. Succinate 262 247 147 Fumarate 260 245 143 [M-117]+ fragment is not accurate. Serine 321 306 204 Threonine 263 248 146 α-ketoglutarate 273 258 158 The first and fifth carbon link to form a cycle. 319 304 302 Aspartate 349 334 232 Both fragments are not accurate. Glutamine 363 348 246 Malate 350 335 333 Citrate 480 465 463 Both fragments are not accurate. References 1. Wahl SA, Dauner M, Wiechert W: New tools for mass isotopomer data evaluation in 13C flux analysis: Mass isotope correction, data consistency checking, and precursor relationships. Biotechnol Bioeng 2004, 85(3):259-268.