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Magnetoresistive (MR) sensors have been identified as promising candidates for the development of high-performance magnetometers due to their high sensitivity, low cost, low power consumption, and small size. The rapid advance of MR sensor technology has opened up a variety of MR sensor applications. These applications are in different areas that require MR sensors with different properties. Future MR sensor development in each of these areas requires an overview and a strategic guide. A MR sensor roadmap (non-recording applications) was therefore developed and made public by the Technical Committee of The IEEE Magnetics Society with the aim to provide an R&D guide for MR sensors intended to be used by industry, government, and academia. The roadmap was developed over a three-year period and coordinated by an international effort of 22 taskforce members from 10 countries and 17 organizations, including universities, research institutes, and sensor companies. In this paper, the current status of MR sensors for non-recording

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Marine biotoxins pose a significant food safety risk when bioaccumulated in shellfish, and adequate testing for biotoxins in shellfish is required to ensure public safety and long-term viability of commercial shellfish markets. This report describes the use of a benchtop Orbitrap system for liquid chromatography-mass spectrometry (LC-MS) screening of multiple classes of biotoxins commonly found in shellfish. Lipophilic toxins such as dinophysistoxins, pectenotoxins, and azaspiracids were separated by reversed phase LC in less than 7 min prior to MS data acquisition at 2 Hz with alternating positive and negative scans. This approach resulted in mass accuracy for analytes detected in positive mode (gymnodimine, 13-desmethyl spirolide C, pectenotoxin-2, and azaspiracid-1, -2, and -3) of less than 1 ppm, while those analytes detected in negative mode (yessotoxin, okadaic acid, and dinophysistoxin-1 and -2) exhibited mass errors between 2 and 4 ppm. Hydrophilic toxins such as domoic acid, saxitoxin, and gonyautoxins were separated by hydrophilic interaction LC (HILIC) in less than 4 min, and MS data was collected at 1 Hz in positive mode, yielding mass accuracy of less than 1 ppm error at a resolving power of 100,000 for the analytes studied (m/z 300-500). Data were processed by extracting 5 ppm mass windows centered around the calculated masses of the analytes. Limits of detection (LOD) for the lipophilic toxins ranged from 0.041 to 0.10 μg/L (parts per billion) for the positive ions, 1.6-5.1 μg/L for those detected in negative mode, while the domoic acid and paralytic shellfish toxins yielded LODs ranging from 3.4 to 14 μg/L. Toxins were detected in mussel tissue extracts free of interference in all cases.

This paper presents an application of ultrahigh-performance liquid chromatography and electrospray ionization quadrupole Orbitrap high-resolution mass spectrometry (UHPLC/ESI Q-Orbitrap) for determination of 166 pesticide residues in fruits and vegetables. Pesticides were extracted from the samples using the QuEChERS (quick, easy, cheap, effective, rugged, and safe) procedure. UHPLC/ESI Q-Orbitrap MS (i.e., full MS scan) acquired full MS data for quantification, and UHPLC/ESI Q-Orbitrap dd-MS(2) (i.e., data-dependent scan) obtained product-ion spectra for confirmation. UHPLC/ESI Q-Orbitrap MS quantification was achieved using matrix-matched standard calibration curves with isotopically labeled standards or chemical analogues as internal standards. The method performance characteristics that included overall recovery, intermediate precision, and measurement uncertainty were evaluated according to a nested experimental design. For the matrices studied, about 90.3-91.5% of the pesticides had recoveries between 81 and 110%, 92.1-97.6% had intermediate precision ≤20%, and 89.7-95.2% had measurement uncertainty ≤40%. Confirmation was based on mass accuracy ≤5 ppm and LC retention time tolerance within ±2.5%. Overall, the UHPLC/ESI Q-Orbitrap has demonstrated great performance for quantification and confirmation of pesticide residues in fresh fruits and vegetables.