Facile one-pot synthesis of a aptamer-based organic–silica hybrid monolithic capillary column by “thiol–ene” click chemistry for detection of enantiomers of chemotherapeutic anthracyclines

In the current study, we developed a facile strategy for the one-pot synthesis of an aptamer-based organic–silica hybrid monolithic capillary column. A 5′-SH-modified aptamer, specifically targeting doxorubicin, was covalently modified in the hybrid silica monolithic column by a sol–gel method combined with “thiol–ene” click reaction. The prepared monolithic column had good stability and permeability, large specific surface, and showed excellent selectivity towards chemotherapeutic anthracyclines of doxorubicin and epirubicin. In addition, the enantiomers of doxorubicin and epirubicin can be easily separated by aptamer-based affinity monolithic capillary liquid chromatography. Furthermore, doxorubicin and epirubicin spiked in serum and urine were also successfully determined, which suggested that the complex biological matrix had a negligible effect on the detection of doxorubicin and epirubicin. Finally, we quantified the concentration of epirubicin in the serum of breast cancer patients treated with epirubicin by intravenous injection. The developed analytical method is cost-effective and rapid, and biological samples can be directly analyzed without any tedious sample pretreatment, which is extremely useful for monitoring medicines in serum and urine for pharmacokinetic studies.