pubmed-article:3578766 | pubmed:abstractText | We used gas chromatography-mass spectrometry to assay putrescine in minute regions of single rat brains. Acid extraction, partial purification on Amberlite CG 120, and derivatization with pentafluoropropionic anhydride preceded the gas chromatography-mass spectrometry. A moving-needle solventless system and a direct inlet system were also used to increase sensitivity. Putrescine was measured accurately at the picomole level; the mean concentration of this polyamine in five regions of rat brain found by this method was 2.7-3.8 times higher than reported by other researchers. | lld:pubmed |