Measurement of the Ratio of Lecithinto Sphingomyelin in Amniotic Fluid by Fast Atom Bombardment Mass Spectrometry

FAB-MS, fast atom bombardment mass spectrometry; DPL, di-palmitoyllecithin; PS, palmitoylsphingomyelln; d6-DPL, i-3-di1pa1mitl-16,16,16.2H3]-phosphatidylcholune; and L/S, total lec-ithin/total sphingomyelin ratio. Editor’s note (added in proof): A related paper was published in this journal in 1983(29:1349-53). The earlier paper is no longer in some current databases of the medical literature and thus may be overlooked. The two papers are complementary, each with infor-mation not available in the other. See also the related editorial in this issue (pp 1321-2)