Abstract
The 2-state and sequential models for positive cooperativity in ligand binding can produce significantly different theoretical binding curves when presented in a Scatchard plot. The conditions that produce the greatest differences were examined. The theoretical differences were used to select the 2-state model as the best model for describing the binding of acetylcholine to [Torpedo californica electroplax] acetylcholine receptors that were solubilized by Triton X-100 and sodium cholate.