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How to flush a clogged HPLC flow cell - WKB1930

Article number: 1930


  • Unclog an HPLC flow cell
  • How to reverse flush a flow cell?


  • 2487 Dual-Wavelength Absorbance Detector
  • 996/2996 PDA Detector
  • 2489 UV/Vis Detector
  • 2998 Photodiode Array Detector
  • 2414 Refractive Index Detector


  1. Prepare a suitable solvent or 6M nitric acid solution.

    A suitable solvent depends on the nature of the blockage and on which detector. Some blockages require warm water, methanol, or nitric acid. A customer should consult their detector's user manual to determine a suitable solvent for flushing.

  2. Remove the solvent filter and prime the system.
  3. Replace the column with a union.
  4. Reverse the flow cell inlet and outlet lines.
  5. Start the flow at a very low rate, ensuring that the back pressure remains below the maximum rating (1000 psi for UV, 100 psi for RI) for the flow cell.
  6. Flush at a low flow for at least one hour.
  7. Flush with HPLC grade water until the effluent returns to neutral.



This is outlined section 4.3.1 Flushing the Flow Cell of the 2487 Dual-Wavelength Absorbance Detector Operator's Guide

2414, 2414B, 2487, 2489, 2489B, 2489SFC, 2996, 2998, 2998B, 996, 996UP, A-10PDA, A-10RI, A-10UV

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