Method Study On New Matrix To Analysis Of BaP By MALDI-TOF

Benzo(a)pyrene is a kind of polycyclic aromatic hydrocarbon compound, composed of a benzene ring and a pyrene molecules, often found in vegetable oils, dairy products, baked fish, bacon and other food. As one of the three carcinogens, benzo(a)pyrene content belongs to trace levels, so it is difficult to accurately determine their quantity.Matrix Assisted Laser Desorption Ionization/Time of Flight-Mass Spectrometer(MALDI-TOF/MS) is one of the soft ionization technique, greatly used in the field of detecting technology for it's high-throughput screening and simple sample preparation.Based on the tradition matrix often produce interference peaks in the low molecular weight(m/z < 600), thus it's important to developed a new kind of materials for MALDI-TOF/MS matrix to detect small molecules.In this study, the metal organic framework material synthesized by solvent thermal method, the prepared material were characterized by UV visible spectroscopy (UV-Vis),fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and X-ray diffraction (XRD). The results show that the metal organic framework material own a uniform surface, present regular dodecahedron, absorption accord with the requirements of the instrument. Compared with the traditional matrix and metal organic framework material detection of benzo(a)pyrene, the results show that the mass spectra is relatively clean and high sensitivity by MIL-101 (Fe) as matrix. In order to evaluate the application of the MIL-101(Fe) as a new matrix for MALDI, the factors influence the analysis process such as the dispersants and concentration for MIL-101(Fe), sample preparation, steel type and laser energy were investigated and optimized. Under the optimized conditions, good linearity with a determination coefficient (R2) above 0.99 was built between the range of 0.25 to 50?g L-1 with a relative standard deviations of 9.9% (n = 15). Limit of detection (LOD) was low as 0.1?gL-1.Furthermore, we realized the analysis of BaP in four vegetable oils samples, sesame oil, linseed oil, tea oil and olive oil, spiked( add the high, middle and low level respectively 10,1 and 0.5 ?g kg-1) and analyzed in simple pretreatment technology by MALDI-TOF/MS when MIL-101(Fe) as matrix. High recovery values obtained in these four oils were between 80.0%-114.8% , relative standard deviations were less than 13.7% (n = 5). The results indicated that the established method has higher accuracy and reproducibility, can meet the needs of actual sample analysis.