Significant analytical challenges of the measurement of GH include its existence in several structural forms in blood circulation. GH is known to circulate in monomeric or single forms, dimeric or double forms, and oligomeric or multiple forms, up to a pentameric (5-molecule isoform).
Most current commercial immunoassays employ chemiluminescent immunoassay principles with antibodies directed against monomeric forms of GH, which accounts for most of the GH in circulation.
