Objective: To establish a determination for docetaxel that derives from mice plasma and tissue fluid samples

and evaluate effectiveness for this method. Method: Samples were purified by methyl tert-butyl ether with paclitaxel as internal standard.Chromatographic separation was performed on a Hypersil BDS C18 column using a mobile phase composed of methanol-0.1% formic acid(80:20)

column temperature was 40℃

flow rate was 0.3 mL·min-1.Detection was performed on atriple-quadrupole tandem mass spectrometer with multiple reaction monitoring (MRM) mode via electrospray ionization (ESI) source

ESI voltage was 3.5 kV

capillary temperature was 320℃

sheath gas pressure was 35 Pa

auxiliary gas pressure was 10 Pa

collision energy was 30 V

CID pressure was 12 V

detection ion for docetaxel was m/z 876.3-549.1

detection ion for paclitaxel was m/z 830.3-307.9. Result: Docetaxel in mice plasma

heart

liver

spleen

lung and kidney showed good linear relationship within 0.013-13

0.012-12.937

0.013-13.068

0.012-13.001

0.013-13.133

0.011-12.965 mg·L-1.RSD of intra-day and inter-day assays were less than 15%.Recovery rates of docetaxel with low

middle and high concentration in plasma were 98.24%

97.51% and 93.70%

its recovery rates in heart

liver

spleen

lung and kidney were 87.87%-98.90%. Conclusion: Compared with HPLC

LC-MS/MS is more suitable for quantitative analysis of docetaxel in mice plasma and tissue fluid samples.