A High Performance Liquid Chromatographic Method for Histamine in Plasma Using Solid Phase Extraction and Fluorescamine Derivatization

A reversed phase HPLC method for the determination of histamine in plasma was developed using solid phase extraction with fluorescamine derivatization. Betazole was used as an internal standard. Histamine and the internal standard were extracted from plasma using a cation exchange solid phase extraction cartridge, derivatized precolumn and the derivatized extracts were separated on a C8 column. The solid phase extraction provided recoveries of 85–90%. The method was found to be linear through the range of 1–10 ng/ml and the histamine derivative was stable at 4°C for 18 hours. The method was found to be accurate to within 7% bias and precise to within 18% CV. Selectivity could not be rigorously assessed because of endogenous histamine, although comparison to RIA results suggested good selectivity. The limit of detection was calculated to be 13 pg on column, although the current method was limited by the small proportion of sample injected on column. The method is sufficient for measuring histamine levels expected during allergic response.