Table 1.
Organic acids with their respective retention time and specific ion masses used for their identification and quantification by GC–MS
| Organic acid | Precursor ion | Product ion | Retention time (in min) |
|---|---|---|---|
| Lactic acid | 219 | 191 | 9.128 |
| Oxalic acid | 219 | 190 | 10.295 |
| Pyruvic acid | 247 | 232 | 10.592 |
| Methylmalonic acid | 247 | 218 | 11.554 |
| Ethylmalonic acid | 261 | 217 | 12.531 |
| 2-Ketocaproic acid | 274 | 247 | 13.362 |
| Fumaric acid | 245 | 217 | 13.558 |
| Lactic acid dimer | 291 | 262 | 14.211 |
| Glutaric acid | 276 | 261 | 14.325 |
| 3-Methylglutaric acid | 275 | 247 | 14.573 |
| Succinylacetone | 212 | 182 | 14.880 |
| Adipic acid | 275 | 217 | 15.405 |
| Suberic acid | 303 | 217 | 16.981 |
| Azelaic acid | 317 | 217 | 17.544 |
| Sebacic acid | 331 | 215 | 18.095 |
| Orotic acid | 326 | 311 | 17.28 |