Tamara van Donge

Chapter 6 114 Table 1: Repeatability testing of the LC-MS/MS system with repetition (n=10) using a single sample. n=10 R-ibuprofen S-ibuprofen Mean concentration [µg/mL] 5.86 5.84 SD [µg/mL] 0.09 0.07 CV [%] 1.49 1.21 Table 2 : Inter-and intra assay variation (n=10) to assess precision and accuracy of the low- and high-quality control sample. n= 10 R-ibuprofen (lower QC level) S-ibuprofen (lower QC level) R-ibuprofen (higher QC level) S-ibuprofen (higher QC level) inter -assay µg/mL % µg/mL % µg/mL % µg/mL % Mean concentration 0.49 98.8 0.50 100.7 5.19 103.9 5.12 102.4 SD 0.02 0.02 0.20 0.21 CV 3.60 3.89 3.78 4.13 intra -assay µg/mL % µg/mL % µg/mL % µg/mL % Mean concentration 0.53 105.9 0.52 103.8 4.94 99.1 4.85 97.2 SD 0.02 0.02 0.09 0.08 CV 3.65 3.97 1.75 1.67