The Hill equation revisited: uses and misuses

@article{Weiss1997TheHE,
  title={The Hill equation revisited: uses and misuses},
  author={James N. Weiss},
  journal={The FASEB Journal},
  year={1997},
  volume={11},
  pages={835 - 841}
}
The Hill coefficient is commonly used to estimate the number of ligand molecules that are required to bind to a receptor to produce a functional effect. However, for a receptor with more than one ligand binding site, the Hill equation does not reflect a physically possible reaction scheme; only under the very specific condition of marked positive cooperativity does the Hill coefficient accurately estimate the number of binding sites. The Hill coefficient is best thought of as an “interaction… 
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