203 



Table 4-4 Frequency of observed GC peaks for particular neutral losses and possible 

 compound classes which contribute to these observed neutral losses. The frequency 

 corresponds only to those GC peaks which are directly observable in the 

 chromatograms; therefore, the actual frequency may be higher at the trace level. 

 The mode corresponds to analysis of positive ions (P) or negative ions (N). 



Frequency 



Neutral loss 

 (mode) 



Possible classes 



21 



1(P) 



carboxylic acids, aldehydes, ketones 



20 



28 (?) 



carboxylic acids, aldehydes, ketones 



16 



18 (P) 



carboxylic acids, ketones, alcohols 



15 



46(P) 



carboxylic acids, amino acids 



12 



30 (P) 



carboxylic acids, aldehydes, ketones 



12 



1(N) 



carboxylic acids, ketones 



11 



2(P) 



carboxylic acids, aldehydes, aromatics 



11 



2(N) 



carboxylic acids, alcohols 



9 



44 (N) 



carboxylic acids 



8 



14 (P) 



alkanes, alkenes, alkyl chains 



7 



26 (P) 



aldehydes, cyanides/nitriles 



2 



17 (P) 



amines 



2 



78 (P) 



aromatics 



not tested 



27 (P) 



nitriles 



not tested 



36 (P) 



diols, triols 



not tested 



42 (P) 



ketones 



