Potential of the flowing eluent wall and aliquot on-line detection in the OPLC 50 and 100 systems

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The flowing-eluent-wall (FEW) procedure is suitable for single and multi-channel on-line overpressured-layer chromatographic (OPLC) separation by operational segmentation of a non-segmented adsorbent bed. One pump only is used to deliver mobile phase and the samples can be injected in parallel on to the non-segmented layer in specific areas determined by the positions of inlet troughs. To prevent mixing of samples from adjacent lanes, mobile phase and samples are introduced to the layer at the sample-introduction positions and at the sides, so the bed is divided into active parts, where separation is performed, and non-active parts, where there is no separation. The FEW arrangement can be used at the inlet (FEW-I) or at both inlet and outlet (FEW-I/O) enabling separate detection and collection of the separation and FEW lines. The OPLC 50 system with the four-channel FEW-I/O configuration is suitable for fully off-line parallel separations and for four-channel fully on-line separations. One or two-channel on-line separations can be achieved by inserting the appropriate cassette. The newly developed experimental OPLC 100 separation unit has the FEW-I/O arrangement and applies 10 MPa external pressure to the surface of 5 cm x 20 cm layers. By use of the appropriate cassette fully off-line and one or two-channel fully on-line separation can be performed. Because of the 10-MPa external pressure the system enables more efficient fully off-line separation than systems of previous generations. Fully on-line separation can also be performed with aliquot detection, a new type of on-line detection of partially mixed samples in which the regions where mixing of parallel samples occurs is excluded. This enables more efficient separation than the original FEW-I/O arrangement.

Original languageEnglish
Pages (from-to)97-102
Number of pages6
JournalJournal of Planar Chromatography - Modern TLC
Issue number2
Publication statusPublished - Apr 1 2008



  • Aliquot on-line detection
  • Efficiency
  • Flowing eluent wall (FEW)
  • OPLC 100 separation unit
  • OPLC 50 separation unit
  • Overpressured-layer chromatography (OPLC)
  • Polyalcohols

ASJC Scopus subject areas

  • Analytical Chemistry
  • Biochemistry
  • Clinical Biochemistry

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