Partitioning of troglitazone and rosiglitazone into lipid bilayers. (A) Heat production as a function of time as 2-µl aliquots of a 10-mM lipid vesicle solution is injected into 200 µM of rosiglitazone solution. Each injection results in a peak in the energy versus time signal (left); the area under the peak corresponds to the enthalpy of partitioning for that injection, which is plotted as a function of the injection number (▪, right panel). The solid line denotes the fit of Eq. 7 to the results to determine the partition coefficient (⁠$KPW→L$⁠) and the molar enthalpy of partitioning (⁠$ΔHPW→L$⁠). (The partitioning of troglitazone was tested by titrating 30 µM troglitazone with 3 mM lipid.) (B) The partition coefficient $KPW→L$ (solid fill bars) and $logKPW→L$ (hatched fill bars) for troglitazone (olive) and rosiglitazone (pink). (C) $ΔGPW→L$ (dark filled bars), $ΔHPW→L$ (light filled bars), and $TΔSPW→L$ (open bars) for troglitazone (TRO, pink) and rosiglitazone (ROS, pink). n = 3; error bars are plotted.