Exploring the effects of cooperative interactions on affinity using a pinwheel sensor system

A series of three pinwheel sensors were constructed with 1, 2, and 3 binding sites. Binding of Zn+2 and Cd+2 was monitored by fluorescence over a range of temperatures. The data demonstrate that cooperative interactions generally increase the effective affinity of the sensor. This effect is more pronounced in systems which have lower inherent affinity for the analyte.