Detection of serum phospholipids by microchannel-integrated black phosphorus-assisted laser desorption/ionization mass spectrometry

Matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) has been widely applied in the analysis of phospholipids in biological samples. However, it remains a challenge to improve the sensitivity and reproducibility and to control the background noise of matrices. In this study, black phosphorus nanomaterial was used as the matrix of MALDI-MS, and microchannel technique was combined. This microchannel-integrated black phosphorus-assisted laser desorption/ionization (BPALDI) MS approach can effectively detect a variety of lipids with a small amount of sample, and has high sensitivity for phosphatidylcholines (PC) and lysophosphatidylcholines (LPC) with a detection limit of 0.2 μg/mL. Compared with traditional matrices, BPALDI-MS has the advantages of high sensitivity, good reproducibility, and high salt tolerance. This method was successfully applied in the detection of serum PC/LPC ratios in children patients with asthma or bronchopneumonia. This work provides a novel application of black phosphorus matrix and microchannel technique, and gives new insights into method development of rapid screening and identification of disease indicators in biological fluids.