title: Use of microbore columns for the separation of substances of biological origin.
abstract: A gradient system for use with microbore columns is described and the repeatability of the system determined. A simple sampling device for use with aqueous biological samples is described, and the advantages of the high mass sensitivity of microbore columns for the analysis of such samples are discussed. The sensitivity of the  system is demonstrated by the determination of acetophenone in water at a level of one part per billion. The use of the apparatus for the separation of low-molecular-weight, non-ionic compounds contained in blood is also demonstrated. It is shown that excellent separations of such components can be obtained from as little as 400 microliter of serum.
mesh_terms: D001774:Blood Chemical Analysis / Q000379:methods; D002853:Chromatography, Liquid / Q000295:instrumentation* / Q000379:methods; D006801:Humans; D014556:Urine / Q000032:analysis