Recipe
Methylmalonic Acid
Methylmalonic Acid in Serum / Plasma / Urine, advanced
Methylmalonic acid (MMA) serves for the assessment of the vitamin B12 status. Vitamin B12 deficiency leads to an increased MMA concentration in plasma, serum and urine. Our new ClinMass® Complete Kit enables a fast and reliable MMA analysis from all three matrizes. For serum and plasma samples the sample preparation consists of a single pipetting step. The sample matrix is removed by precipitation while the internal standard IS (d3-MMA) is added. Urine samples can be injected directly after dilution and IS addition. The subsequent LC-MS/MS analysis is performed within a 3 min injection interval only. The isobar component succinic acid, which may interfere with MMA, is separated reliably to avoid false positive results. Calibration and quality control is performed in a convenient and cost-efficient way. The method is fully validated using only one (serum) calibration and control set for all three sample matrices (ClinCal® 4-Level Calibrator Set and ClinChek® Controls.
| Test Data | LC-MS/MS Parameters | ||
| Linearity: | LC-Parameters | ||
| -Serum, Plasma | up to 67745 nmol/l | Gradient pump: | Mobile Phase A / B |
| -Urine | up to 1426200 nmol/l | (0.6 ml/min) | |
| LLOD: | Injection volume:: | 5 - 10 µl | |
| -Serum, Plasma | 15 nmol/l | Injection interval:: | 3.0 min |
| -Urine | 391 nmol/l | Column heater: | 40 °C |
| LLOQ: | MS-Parameters | ||
| -Serum, Plasma | 25 nmol/l | Ion-Source: | ESI |
| -Urine | 651 nmol/l | MS/MS-Mode: | MRM |
| Intraassay precision: | 4.3 % | ||
| Interassay precision: | 5.1 % | ||