PFPA-HFIP PAH

In this procedure, the amino groups are acylated with pentafluoropropionic anhydride (PFPA) and the carboxylic groups esterified with hexafluroisopropanol (HFIP) in a one-step procedure (Bertilsson and Costa, 1976), Typically, 100 pL of PFPA and 50 pL of HFIP are added to a freeze-dried or nitrogen-dried tissue extract and the mixture heated at 70°C for 1 h. The samples 

These derivatives have been excellent for analyses of amino acids from neuronal tissues (Fig. 2). However, to analyze the trace levels of ammo acids present in either cerebrospinal fluid or perfusates from release studies, more stable denvatives are preferred. 

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