Compared to ligand-binding assay( LBA) , liquid chromatography coupled to tandem mass spectrometry( LC-MS/MS) methods could improve specificity, reduce the time of method development and enhance efficiency for quantitation of monoclonal antibodies( mAb) .This review summarizes the application of LC-MS/MS assays to the quantitation of mAb in order to facilitate the research of quantitation of mAb in drug development.

Objective To investigate the changes of serum trace elements and nutritional proteins in children with acute lymphoblastic leukemia and acute myeloid leukemia at the stage of onset. Methods Serum levels of cuprum, zinc, iron, magnesium, phosphorus, calcium, ceruloplasmin, ferritin, transferrin, lactate dehydrogenase, total protein, albumin, hemoglobin, and erythrocytes were detected in 73 patients with acute lymphoblastic leukemia, 26 patients with acute myeloid leukemia at stages of onset, and 30 healthy controls using methods including atomic absorption spectrometry, nophelometry assay, dry chemical method, and/or chemiluminescence method. The differences of these indicators among these three groups were analyzed by t test. Results Serum levels of all detected elements except for zinc and phosphorus were significantly different between the onset groups and the control group (P ＜ 0.05 ). Serum levels of cuprum, magnesium, iron, ferritin, ceruloplasmin, and lactate dehydrogenase in the onset groups were significantly higher than those in control group ( all P ＜ 0.05 ). On the contrary, calcium, transferrin, total protein, albumin, hemoglobin, and erythrocyte count were significantly lower in the onset groups than those in control group (P ＜ 0.05). Serum iron, cuprum, zinc, and their metabolism were significantly different between acute lymphoblastic leukemia group and acute myeloid leukemia group ( P ＜ 0.05 ).Conclusion　Serum levels of some trace elements and nutritional proteins are disordered and out of balance in chil dren with acute lymphoblastic leukemia and acute myeloid leukemia at stages of onset.