Irene Doering (Presenter)
RECIPE Chemicals + Instruments GmbH
Bio: In 2007 I finished my studies at the Technical University of Munich with a Diploma Degree of Food Chemistry followed by a PhD Degree at the Ludwig Maximilian University of Munich in 2010. I was working at the Institute of Forensic Medicine in Erlangen for 2 years. In january 2012 I started working at the R&D department of RECIPE Chemicals + Instruments GmbH. I am responsible for the development and validation of methods for newborn screening, homocysteine and methylmalonic acid.
Authorship: Irene Doering, Anke Deden, Katharina Kern
RECIPE Chemicals + Instruments GmbH, Dessauerstr. 3, 80992 Munich, Germany
| Short Abstract RECIPE’s CE IVD certified ClinMass® LC-MS/MS Complete Kit, advanced – Methylmalonic Acid in Serum/Plasma/Urine (MS5100) allows the sensitive and highly selective quantitation of methylmalonic acid (MMA) in serum, plasma and urine. In samples of healthy patients the concentration of MMA - compared to succinic acid (SA) - is present in low concentrations and often requires off-line extraction or derivatisation before analysis. With our approach, the structural isomer SA is chromatographically baseline seperated and simple protein precipitation is sufficient for sample preparation. Therefore, RECIPE’s MS5100 Complete Kit allows the fast and reliable analysis of MMA and can be easily implemented in clinical routine analysis for methylmalonic acidemias. |
Long Abstract
Measurement of methylmalonic acid (MMA) is used as a specific diagnostic tool for a group of disorders collectively called as methylmalonic acidemias. The metabolic pathway involves methylmalonyl-coenzyme A (CoA) being converted into succinyl-CoA with the participation of Vitamin B12. In cases of vitamin B12 deficiency methylmalonyl-CoA accumulates and MMA is subsequently released. Therefore, measurement of MMA can be used to diagnose a number of genetic disorders in this pathway and is elevated in 90-98% of patients with vitamin B12 deficiency even in the early stages of insufficiency when vitamin B12 levels still appear “normal”.
GC/MS has been routinely applied to the quantitation of MMA, however, due to the requirement of derivatisation prior to analysis an alternative method with less time-consuming sample preparation and faster turn-around time is of interest in the clinical laboratories.
The application of LC-MS/MS methods to MMA determination has received increased attention in the last few years, which however still bears some challenges due to the low endogenous concentration of MMA, the highly polar nature, low molecular weight, low pKa and dicarboxylic acid structure. Furthermore chromatographic separation from the naturally occurring structural isomer succinic acid (SA), present in physiological concentrations approximately 50 times higher than MMA, is critical and elementary. Many methods hence require extensive sample preparation steps such as solid-phase extraction, derivatisation, evaporation and/or ultrafiltration.
The RECIPE CE IVD certified ClinMass® LC-MS/MS Complete Kit, advanced – Methylmalonic Acid in Serum/Plasma/Urine (MS5100) was developed for the routine analysis of methylmalonic acid (MMA) in human serum, plasma and urine samples. Sample preparation with its protein precipitation is simple and rapid, and analogous for the different biological matrices. For accurate and precise quantitation, the Complete Kit includes multi-level serum calibrators (4 levels) at clinically relevant levels and two-level serum controls for quality assurance. Matrix effects are compensated using a stable isotope labelled internal standard. Samples are analysed using MRM mode with negative electrospray ionisation for maximum sensitivity and selectivity.
Linearity was found over the range of 0.025 – 67.7 µmol/L in serum/plasma and 0.651 – 1426 µmol/L in urine. The LLOQs achieved by this method were 0.025 and 0.651 µmol/L, respectively. The coefficients of variation for the intra-assay and inter-assay precision were <6.1%.
With RECIPE’s CE IVD certified ClinMass® Complete Kit a highly sensitive and selective method has been realized which enables fast, easy and reliable analysis of MMA and is hence very well suited for clinical routine analysis.
References & Acknowledgements:
| Description | Y/N | Source |
| Grants | no | |
| Salary | yes | RECIPE Chemicals + Instruments GmbH |
| Board Member | no | |
| Stock | no | |
| Expenses | no |
IP Royalty: no
| Planning to mention or discuss specific products or technology of the company(ies) listed above: | yes |