Size exclusion chromatography: An effective tool for the estimation of Sirolimus levels

Sirolimus, a lipophilic macrolide, is a well-known immunosuppressant drug used for coating coronary stents and for preventing rejection of kidney transplants in humans. Since Sirolimus is a relatively large molecule with an average mass 914.172 g/mol, size exclusion chromatography (SEC) was employed for exploring its potential for the estimation of Sirolimus content from blood samples. When human blood samples were spiked with known concentrations of Sirolimus, it was observed that it could be estimated with an average recovery of >90% and relative standard deviation <5%. Results indicated that Sirolimus could be estimated with impressive accuracy and repeatability by SEC technique.