Certain lectin-like humic substances may be present in RO feed waters. A new assay procedure which couples, ammonium sulfate protein precipitation, LC-OCD and Alcian Blue is presented which can detect and quantify these lectin-like humics in any water sample. It appears that bio-adhesion is dependent upon these lectin-like humics and they appear to control biofilm formation.
Based on results from a wastewater RO reclamation facility and examination of the literature, the presence and importance of TEP and their precursors in biofilm formation may be overstated and that biofilm and/or organic fouling on RO membranes appears to be initiated and controlled by the presence of certain lectin-like humics which may not be the dominant conditioning mechanisms in every RO desalination plant.