Reagents & Methodology


HM-JACKarc Methodology

HM-JACKarc uses Integrated Sphere Latex Turbidimetry to measure faecal haemoglobin concentration. The EXTEL HEMO-AUTO HS Latex reagent is composed of consistently sized latex particles. Polyclonal antibodies, specific for human haemoglobin, are bound to the surface of the latex in high concentrations to ensure a very high antigen capture ratio and provide a highly sensitive reagent.

The latex particles have an excess of antibodies to provide a system that will have a hook capacity greater than 200,000ng/ml of haemoglobin (equivalent to 200,000 µg of Hb/g faeces)

This achieves two key benefits:

  • A wide linear dynamic assay range (7µg Hb/g faeces to 400µg Hb/g faeces)
  • A very high hook capacity (200,000 µg Hb/g of faeces) so that it still generates a result for samples higher than the top standard, ensuring no patient is given an artificially low result.

Latex Reagent

Key features:

  • Provides a large concentration of capture antibodies
    • Wide linear dynamic range
      7ng/ml to 400 ng/ml (ng/ml = µg Hb/g faeces)
    • High Hook capacity > 200,000ng/ml
      Ensures no samples will give a falsely lower result
    • Drives reaction kinetics to end stage equilibrium quickly

Each lot of reagent has a factory set reaction response master curve. This is confirmed by performing a local 2 point recalibration to account for local influencing factor.