Reducing Consumable Plastic Malonic Acid Interference in an LC-MS/MS Method to Quantify Serum Methylmalonic Acid

AACC 2022 -- Vitamin B12 is necessary for many processes in the body and is a cofactor in methylmalonic acid (MMA) metabolism. Vitamin B12 deficiency may present with few symptoms, however chronic deficiency may lead to macrocytic anemia, peripheral nerve damage and memory impairment. MMA is measured in the differential diagnosis of vitamin B12 deficiency as elevations in MMA are associated with decreased vitamin B12 stores. Current spectroscopy-based MMA assays require sample extraction processes that place the sample in frequent contact with plastic consumables. Malonic acid is commonly present in lab plastic consumables and it may interfere with quantitation of MMA. We set out to develop and optimize a highly specific method to quantify MMA that was free from malonic acid contamination.