Final answer:
Pharmacokinetic parameters are calculated after collecting and analyzing blood samples from Wistar rats given Psoralea corylifolia extract. Methods include using heparinized tubes, centrifugation, and high-performance liquid chromatography with an internal standard like sophoricoside.
Step-by-step explanation:
To calculate pharmacokinetic parameters such as C-max, tmax, AUC (Area Under the Curve), MRT (Mean Residence Time), and Cl (Clearance) after oral administration of Psoralea corylifolia extract to Wistar rats, the following procedures are generally followed:
- Blood samples are collected into heparinized tubes at various time points post-administration.
- The collected blood is then centrifuged to obtain plasma.
- The plasma concentration of the active compound is quantified using a bioanalytical method, such as high-performance liquid chromatography (HPLC).
- The plasma preparation typically involves precipitating proteins (PP) with methanol; after which water is added and the supernatant is injected into the chromatographic system.
- An internal standard (IS), such as sophoricoside, is used to ensure the accuracy and reproducibility of the analytical results.
The C-max and tmax represent the maximum concentration of the drug in the blood and the time to reach this maximum concentration, respectively. The AUC provides a measure of the drug exposure over time, while MRT gives an indication of the time the drug stays in the body. Clearance refers to the volume of plasma from which the drug is completely removed per unit time.