High-performance liquid chromatography integrated solid-phase extraction in bioanalysis using restricted access precolumn packings

Tailor-made precolumn packings for HPLC integrated extractive clean-up of ( bio)fluids are characterized by possessing a defined diffusion barrier and a biocompatible outer particle surface (restricted access materials, RANI). Only analytes of low molecular mass have free access to the binding center s at the inner pore surface, and thus can be retained and extracted selecti vely. These adsorbents allow the easy, inexpensive installation and economi c operation of fully automated coupled-column systems for repetitive on-lin e solid-phase extraction (SPE), and the subsequent analytical separation of untreated( bio)fluids. (C) 1999 Elsevier Science B.V. All rights reserved.