ABSTRACT
Objective To develop a method of support liquid-liquid extraction (SLE) and simultaneous determination of 4 components in somedon and its 8 metabolites by GC–MS/MS. Methods Somedon and its metabolites were extracted by SLE and determined by GC-MS/MS in MRM mode. The qualitative analysis was based on retention time and ratio of ions. The quantitative analysis was based on internal standard method and calibration curve. Results After SLE and determination of 4 components in somedon and its 8 metabolites, the extraction rate were 37.57%~95.87%, the linear range were 0.12μg/mL~16.00μg/mL, the correlation coefficient(r)were 0.989 6~0.999 7, LOD were 0.08ng/mL~14.48ng/mL, the accuracy were 79.63%~122.90%, the interday and intraday precision were 0.99%~7.43% and 2.19%~10.60% respectively. Conclusion Simultaneous determination of somedon and its metabolites by GC–MS/MS in biological samples, which was rapid, simple, accurate and was high precision and recovery, can be used for qualitative and quantitative analysis in forensic cases.
ABSTRACT
A novel bioanalytical method was developed and validated for the quantitative determination of darunavir (DRV) in rat plasma by employing hydrophilic interaction chromatography and tandem mass spectrometry (HILIC–MS/MS) with supported liquid extraction (SLE). Irbesartan (IRB) was used as an internal standard (IS). The analyte in rat plasma (200 mL) was isolated through SLE using ethyl acetate as the eluting solvent. The chromatographic separation was achieved on Luna-HILIC (250 mm*4.6 mm, 5 μm) column with a mobile phase of 0.1% of formic acid in water:acetonitrile (5: 95, v/v), at a constant flow rate of 1.0 mL/min. The MS/MS ion transitions for DRV (548.1-392.0) and IS (429.2-207.1) were monitored on an ion trap mass spectrometer, operating in the multiple reaction monitoring (MRM) mode. The lower limit of quantitation (LLOQ) was 0.2 ng/mL and quantitation range was 0.2–5000 ng/mL. The method was validated for its selectivity, sensitivity, carryover, linearity, precision, accuracy, recovery, matrix effect and stability. The method was successfully applied to pharmacokinetic study in rats.
ABSTRACT
Three extraction methods were compared for their efficiency to analyze sitagliptin and simvastatin in rat plasma by LC–MS/MS, including (1) liquid–liquid extraction (LLE), (2) solid phase extraction (SPE) and (3) supported liquid extraction (SLE). Comparison of recoveries of analytes with different extraction methods revealed that SLE was the best extraction method. The detection was facilitated with ion trap-mass spectrometer by multiple reactions monitoring (MRM) in a positive ion mode with ESI. The transitions monitored were m/z 441.1→325.2 for simvastatin, 408.2→235.1 for sitagliptin and 278.1→260.1 for the IS. The lower limit of quantification (LLOQ) was 0.2 ng/mL for sitagliptin and 0.1 ng/mL for simvastatin. The effective SLE offers enhanced chromatographic selectivity, thus facilitating the potential utility of the method for routine analysis of biological samples along with pharmacokinetic studies.