Langmuir adsorption isotherm a=rate of diffusion towards a surface u=concentration of the agonist(drug) 0=fraction of area occupied (bound) V=rate of dissociation(evaporation) Rate of diffusion towards surface =aμ(1-61) Rate of evaporation=V Once equilibrium is reached,the rate of 01=- au+V adsorption equals the rate of evaporation: K=equilibrium dissociation constant [AR] [A] p=- [R] 闪+Ka [AR]amount of Agonist and Receptor complex formed Affinity and Efficacy of Drug Drug binds to Receptor with some affinity and form Drug-Receptor complex Drug-Receptor complex generates Stimulus with some efficacy which initiates Response A+R±AR* Stimulus Cellular Stimulus-Response Cascade Response Affinity and Efficacy of drug are parameters independent of cellular systems.θ1 = αµ αµ + V1 ρ = [AR] [Rt ] [A] [A] + KA = Langmuir adsorption isotherm α = rate of diffusion towards a surface V1 = rate of dissociation (evaporation) θ1 = fraction of area occupied (bound) µ = concentration of the agonist (drug) Rate of diffusion towards surface = αµ (1 - θ1 ) Rate of evaporation = V1θ1 Once equilibrium is reached, the rate of adsorption equals the rate of evaporation: KA = equilibrium dissociation constant [AR] = amount of Agonist and Receptor complex formed Drug binds to Receptor with some affinity and form Drug-Receptor complex Drug-Receptor complex generates Stimulus with some efficacy which initiates Response Affinity and Efficacy of Drug Affinity and Efficacy of drug are parameters independent of cellular systems