3-compartment pharmacokinetic model for estimation of talaporfin sodium concentration in interstitial space

We constructed a 3-compartment pharmacokinetic model for canine consisted of three compartments including plasma, interstitial space, and cell to estimate talaporfin sodium concentration change in interstitial space. Photosensitization reaction is performed when talaporfin sodium distributes in the interstitial space employing a short drug-light interval in our arrhythmia ablation. We studied interstitial concentration constructing the 3-compartment numerical model using talaporfin sodium concentration in canine plasma, and in addition, other measured relative concentrations of canine tissue, including plasma, interstitial space and cell information. We represented differential rate equation of the drug concentration in each compartment. Fitting the measured data set to the calculated concentration in each compartment, the rate constants in the constructed 3-compartment model were determined with R²=0.98. Using the 3-compartment model, the interstitial talaporfin sodium concentration and the available condition in our arrhythmia ablation could be estimated.