运用Orbitrap高分辨质谱结合DART离子源实现高通量食品安全控制
简介
In recent years, substantial developments have taken place in the field of mass spectrometry, enabling the introduction of a number of novel ambient desorption ionization techniques such as direct analysis in real time (DART®), desorption electrospray ionization (DESI),3 surface desorption atmospheric pressure chemical ionization (DAPCI) and atmospheric solids analysis probe (ASAP™). These novel ion sources are characterized by remarkably high throughput of analyses which can be carried out under ambient conditions without (chromatographic) separation of sample components prior to desorption/ionization or the need for complicated and time demanding sample pre-treatment procedures. The DART technology employed in this study relies upon fundamental principles of atmospheric pressure chemical ionization (APCI). Excited-state helium atoms produce reactive species for analyte ionization.Numerous applications of the DART ion source coupled to various types of mass spectrometers have been reported. DART found its use in many areas of analytical chemistry as a tool for rapid qualitative analysis of numerous compounds. Due to the relatively high signal fluctuation of ion intensities obtained by repeated DART measurements, an internal standard usually has to be employed for compensation during quantitative analysis. However, implementation of Vapur® gas ion separator and automatic sampling systems were reported to significantly improve the repeatability for some analytes.
实验仪器
结论
The results presented in this application note demonstrate the feasibility of DART ionization source in combination with Exactive mass spectrometer for the rapid detection and quantification of various food contaminants, including set of priority mycotoxins and melamine selected as an example. Comparable trueness of generated results was achieved by applying isotope dilution-based quantification and matrix-matched calibration to compensate for signal suppression and other matrix effects that unavoidably occur during direct analysis of real matrix samples. The major advantages of the combination of ambient ionization technique with Exactive mass spectrometry are the simplicity of operation, day-to-day robustness and broad application range. In addition, ultra highresolution provided by Exactive mass analyzer helps to solve some of the problems caused by isobaric interferences from matrix components. The choice of ultra high-resolution mass spectrometer such as Exactive is one of the key requirements when considering the application of DART ionization as a reliable tool in the food laboratory.
