04 [micro]g/g and does not exhibit a high-dose hook effect
up to 64,800 [micro]g/g.
Screening method to evaluate point-of-care human chorionic gonadotropin (hCG) devices for susceptibility to the hook effect
by hCG E core fragment: evaluation of 11 devices.
The hook effect
has long been recognized (4, 5), and current automated protein analyzers have been optimized to detect and mediate the hook effect
After the base model was selected, we developed incrementally more complex models that then included a hook effect
and interaction terms between hook and other factors.
The capacity of the equipment ensures there is no cross-reactivity with near neighbour strains or household powders; no set up time is required; it does not need expensive readers; decontamination is not necessary; there are no false positives or false negatives and there is no hook effect
However, most manufacturers have developed devices that can bind very high hCG concentrations, and today the hook effect
occurs primarily in the presence of pathologically increased hCG such as gestational trophoblastic disease [i.
9) The hook effect
can cause very low hCG results or false-negative results when an extremely high hCG concentration is present due to the saturation of all antibody-binding sites on both the capture and signaling antibodies, permitting few or no complex formation.
The equipment detects the presence of these agents in as little as 3 minutes with no hook effect
We refer to this phenomenon as the variant hook effect
This is especially true for certain immunoassays susceptible to the hook effect
, such as tumor markers that can vary in concentration over several orders of magnitude.
If a hook effect
is present, the concentration of the diluted sample will be markedly greater than the undiluted sample.
Unfortunately, in the interim period, the initial lab had discontinued its initial platform, so there was no way to assay the high value on the initial platform to determine if the hook effect
was the problem.