We present a multi-residue instrumental method that can be applied for high-throughput screening and semi-quantitation of pesticide residues in food matrices at or below the current legislative requirements. A high-resolution, accurate-mass mass spectrometer operated in Full Scan – Variable Data-Independent Analysis (FS-vDIA)* mode provided an option for full spectrum filtering, retrospective analysis, and multi-parameter-based compound identification. The method was validated for 328 target pesticides, with an option for the future extension to a larger number. (*vDIA not available in US.)

This application note demonstrates a simple combustion ion chromatography (CIC) method to determine fluoride in tea. Using the CIC system including a Mitsubishi Automatic Combustion Unit AQF-2100H system and a Thermo Scientific Dionex Integrion HPIC system, fluoride in tea is determined in 20 min (11 min if the combustion and chromatography functions are overlapped), a significant time savings over the current Chinese national method which requires more than a hour. The CIC method is sensitive (MDL=1 ppm), precise, and accurate. The only sample preparation required is to grind and dry the tea.

Analysis of pesticide residues has been one of the most important tasks of food safety laboratories. Mass spectrometers (MS), with liquid chromatography coupled to triple stage quadrupole mass spectrometers (LC-MSMS), have been the main tools used in pesticide residue analysis. There is a consensus that sample preparation is becoming the bottleneck to the entire workflow. We developed a rapid and sensitive automated online sample preparation LC-MS/MS method to screen for multiple pesticides in green tea extract.

We demonstrate a complete analytical metabolomic workflow including (1) data acquisition using a high resolution accurate mass instrument that is equipped with a Higher Energy Collisional Dissociation (HCD) cell and coupled to a high pressure LC (Figure 1), (2) metabolite differential abundance analysis, and (3) structural elucidation of relevant metabolites using accurate mass and HCD fragmentation information to highlight the component differences between green and black tea.

Alkanolamines are important in the chemical, pharmaceutical, and petroleum industries. Their analysis is also important in metal surface finishing and in wastewater effluents. Ion chromatography (IC) works particularly well for separations of alkanolamines. This application update describes the use of the OmniPac PAX-500 column with Pulsed Amperometric Detection (PAD) to measure alkanolamines.