CACI-MS1 and CACI-MS2 spectra of 20:3 FAME. A) CACI-MS1 spectrum showing m/z 374, 321, 289, and 271 characteristic ions of 20:3 FAME. B) CACI-MS/MS spectrum of the m/z 374 ion positively identifying 5,11,14-20:3 based on the detection of diagnostic ions m/z 304 and 192 for the diene and m/z 272 vinylic to the isolated double bond, for the peak at the expected chromatographic retention time.