ANALYTICAL METHOD VALIDATION OF DOXORUBICIN AND DOXORUBICINOL IN VOLUMETRIC ABSORPTIVE MICROSAMPLING BY LIQUID CHROMATOGRAPHY-TANDEM MASS SPECTROMETRY

Doxorubicin is a broad-spectrum anthracycline antibiotic which has antineoplastic activity. Doxorubicin can cause cardiotoxic effects due to the formation of doxorubicinol as its main metabolite. One of the latest bio sampling methods, Volumetric Absorptive Microsampling (VAMS), has various advantages which include blood sampling by finger-prick, hematocrit does not influence it, and it can be stored at room temperature. This study aims to determine the optimum analysis conditions and sample preparation method in VAMS with daunorubicin as an internal standard, and to develop sensitive, specific measurements as well as validate the analytical method using Ultra High Performance Liquid Chromatography-Tandem Mass Spectrometry (UPLC-MS/MS). Analytical quantification analysis using mass spectrometry with a mass analyzer type is a triple quadrupole with a positive type of electrospray ionization (ESI). The separation was carried out with the Acquity® UPLC BEH C18 column (2.1 x 100 mm; 1.7 μm), with a flow rate of 0.2 mL/min, and gradient elution using 0.1% formic acid in water and 0.1% formic acid in acetonitrile for 7 minutes. Multiple reaction monitoring (MRM) values were set at m/z 544.22 > 396.9 for doxorubicin; m/z 546.22 > 398.9 for doxorubicinol; and m/z 528.5 > 362.95 for daunorubicin. Sample preparation used protein precipitation with methanol as the extracting solution, the drying time of the VAMS was 2 hours, and the sonication time was 30 minutes. LLOQ values obtained were 8 ng/mL for doxorubicin and 3 ng/mL for doxorubicinol with the linearity of 0.9904 for doxorubicin and 0.9902 for doxorubicinol.