Underivatized Nonesterified Fatty Acid

It should be recognized that following the same line of reasoning, low-energy MS analysis has also been used to identify the location of double bond(s) of TAG [7] and glycerophospholipids [9]. However, this type of work currently belongs more to the research laboratory than to the practical lipidomics application. 

2 Negative-Ion Mode The fragmentation pattern of deprotonated NEFA species in the negative-ion mode (i.e., [M-H] ) contains a characteristic ion peak 

FRAGMENTATION PATTERNS OF FATTY ACIDS AND MODIFIED FATTY ACIDS 

0 FA species with 1st double bond at c4 FA species with 1st double bond at  

Number of double bonds in FA species with 22 carbon atoms 

---