MALDI-TOF Mass Spectrometry Based on Parylene-Matrix Chip for the Analysis of Lysophosphatidylcholine in Sepsis Patient Sera.

ABSTRACT

In this work, medical diagnosis of sepsis was conducted via quantitative analysis of lysophosphatidylcholine 160 (LPC 160) by using matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) mass spectrometry based on a parylene-matrix chip. In the first step, specific mass peaks for the diagnosis of sepsis were searched by comparing MALDI-TOF mass spectra of sepsis patient sera with healthy controls and pneumonia patient sera. Two mass peaks at m/z = 496.3 and 518.3 were chosen as those that are specifically different for sepsis sera to compare with healthy controls and pneumonia patient sera. These mass peaks were identified to be protonated and sodium adducts of LPC 160 by using tandem mass spectra (MS2 and MS3) of purely synthesized LPC 160 and extracted LPC 160 from a healthy control and a sepsis patient. In the next step, a standard curve for LPC 160 for the quantitative analysis of LPC 160 with MALDI-TOF MS based on the parylene-matrix chip was prepared, and the statistical correlation to the LC-MS analysis results was demonstrated by using the Bland-Altman test and Passing-Bablok regression. Finally, MALDI-TOF MS based on the parylene-matrix chip was used for the quantification of LPC 160 with sera from patients with severe sepsis and septic shock (n = 143), pneumonia patients (n = 12), and healthy sera (n = 31). The sensitivity and the selectivity of medical diagnosis of sepsis was estimated to be 97.9% and 95.5% by using MALDI-TOF MS based on the parylene-matrix chip, respectively.