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Polychlorinated biphenyls (PCBs) analysis using a miniaturized high-resolution time-of-flight mass spectrometer "MULTUM-S II".

In this study, we conducted polychlorinated biphenyls (PCBs) analysis using fast gas chromatography (GC)/high-resolution mass spectrometry (HRMS). Mass spectrometry (MS) was performed with a miniature multi-turn time-of-flight (TOF) analyzer called "MULTUM-S II". MULTUM-S II is truly a portable high resolution mass spectrometer. The mass spectrometer's high resolution capability is due to its theoretical infinite flight path utilizing perfect space and time focusing within a closed flight orbit. Mass resolution above 10 000 was easily achievable employing this portable system. This mass resolution is comparable to magnetic sector mass spectrometers, which have traditionally performed PCB analyses in the past. At a resolution of 10 000, a limit-of-detection of 1 ppb was determined using a heptachlorinated biphenyl standard sample. Using this fast GC/HRMS, 66 PCB congeners were analyzed within 5 min. In addition experiments aimed at confirming interference of PCB signal peaks and matrix peaks in diluted dielectric coolant fluids were performed. We found that the PCB signal peaks were detected without matrix interference via high mass resolution.