Table 3 Uncertainty sources in the determination of trans- and cis-vitamin K1 by the developed ID-LC/MS/MS method. The samples are spinach (A) and kimchi cabbage (B)
Uncertainty components | Sources (evaluation method) | Typical value (%) | |
|---|---|---|---|
trans-vitamin K1 | cis-vitamin K1 | ||
(A) | |||
Standard solution | Purity of the reference material (from the KRISS purity analysis) | 0.2 | 0.1 |
Gravimetric preparation (from the cross-check of the independent sets of calibration solutions) | 2.0 | 2.1 | |
Isotope ratio standard | Gravimetric mixing (from the cross-check of multiple isotope ratio standards from each individual standard solution) | 2.1 | 2.1 |
Peak area ratio of the standard and isotope-labeled standard from the LC/MS/MS measurements of the isotope ratio standard | Repeatability of multiple measurements | 1.1 | 1.4 |
Mass of the sample taken for analysis | Readability and linearity of the balance used (from the certificate of the balance) | < 0.01 | < 0.01 |
Mass of the isotope-labeled standard solution spiked into the sample taken for analysis | Readability and linearity of the balance used (from the certificate of the balance) | < 0.01 | < 0.01 |
Peak area ratio of the standard and isotope-labeled standard from the LC/MS/MS measurements of the sample extracts | Repeatability of multiple measurements | 0.4–1.5 | 0.5–2.6 |
(B) | |||
Standard solution | Purity of the reference material (from the KRISS purity analysis) | 0.2 | 0.1 |
Gravimetric preparation (from the cross-check of the independent sets of calibration solutions) | 2.0 | 2.1 | |
Isotope ratio standard | Gravimetric mixing (from the cross-check of multiple isotope ratio standards from each individual standard solution) | 2.1 | 2.1 |
Peak area ratio of the standard and isotope-labeled standard from the LC/MS/MS measurements of the isotope ratio standard | Repeatability of multiple measurements | 1.1 | 1.4 |
Mass of the sample taken for analysis | Readability and linearity of the balance used (from the certificate of the balance) | < 0.01 | < 0.01 |
Mass of the isotope-labeled standard solution spiked into the sample taken for analysis | Readability and linearity of the balance used (from the certificate of the balance) | < 0.01 | < 0.01 |
Peak area ratio of the standard and isotope-labeled standard from the LC/MS/MS measurements of the sample extracts | Repeatability of multiple measurements | 0.5–1.3 | 0.8–2.5 |