![]() Meanwhile, using 9-xanthydrol as derivative, Luo et al. Furthermore, an electrochemical immunosensor was established with a polyclonal antibody (pAb) specific for AA-4-MPA as recognition element, achieving a 100-fold improvement in sensitivity and decreasing analysis time in comparison to the original ic-ELISA 15. prepared a monoclonal antibody (mAb) against the derivative of AA (4-mercaptophenylacetic acid derivatized AA, AA-4-MPA) and developed an indirect competitive enzyme-linked immunosorbent assay (ic-ELISA) for AA determination 14. Till now, several immunoassays have been reported for AA 11– 13. Alternatively, immunoassays based on the specificity of antibodies to recognize target antigens are paid more attention for their excellent sensitivity, high-throughput screening and ease of combination with other detection formats, especially in detection of small molecule compounds in foodstuffs. Most of them suffer significantly from high instruments cost and complex operations, such as high-performance liquid chromatography (HPLC), gas chromatography (GC) and capillary electrophoresis (CE) separations 8– 10. So far, some methods have been used to quantify AA in foodstuffs. Therefore, given its toxicity and high pollution levels, a rapid, portable and highly sensitive detection method for AA would be helpful in monitoring the safety of foodstuffs more conveniently and making dietary exposure assessment with more extensive coverage. However, the reference level for AA in potato crisps was monitored as 750 μg/kg by the European Union (EU) 7. In 2015, European Food Safety Authority (EFSA) regulated that the amount of AA in potato crisps should be below the indicative value of 1000 μg/kg 6. showed that the mean amounts of AA in the cocktail snacks were the highest among the detected food samples and up to 1060 μg/kg, then gingerbread with 890 μg/kg and chips with 351 μg/kg 5. Since it was found and firstly reported in fired or oven-cooked carbohydrate-rich foods in 2002 3– 4, food-borne AA contamination has been getting more and more public concern. Therefore, it was listed by the International Agency for Research on Cancer as a probable human carcinogen in group 2A 2. Finally, the analytical performance of ECIA was validated by the standard ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS).Īcrylamide (AA, Mw 71.08 Da) is a vinylic hazardous chemical, which has inherently toxic properties, including neurotoxicity, reproductive toxicity, and carcinogenicity 1. The average recoveries ranged from 88.29% to 111.76% in spiked baked biscuits and potato crisps. The LOD was low to 0.033 μg/mL, 3-fold improved than that of ic-ELISA and a wider linear detection range from 0.39 μg/mL to 50.0 μg/mL was achieved. Furthermore, an enhanced electrochemical immunoassay (ECIA) was developed based on the optimized reaction conditions. Firstly, an ic-ELISA was established for acrylamide with the limit of detection (LOD) of 0.089 μg/mL and working range from 0.23 μg/mL to 5.6 μg/mL. Herein, a specific nanobody termed Nb-7E against acrylamide derivative xanthyl acrylamide (XAA) was isolated from an immunized phage displayed library and confirmed to be able to detect acrylamide. Symbols, abbreviations, or full names for units of length,Īrea, mass, pressure, and other types.Acrylamide is toxicant aliphatic amide formed via the Maillard reaction between asparagines and reducing sugars during food heat processing. You can find metric conversion tables for SI units, as wellĪs English units, currency, and other data. The unit is named after Blaise Pascal, the eminent French mathematician, physicist and philosopher.Ĭonversion calculator for all types of measurement units. The pascal (symbol Pa) is the SI unit of pressure.It is equivalent to one newton per square metre. The definition of a pascal is as follows: The SI prefix "mega" represents a factor of Thus a reading of 30 psig on a tire gauge represents an absolute pressure of 44.7 psi. ![]() If a pressure gauge is calibrated to read zero in space, then at sea level on Earth it would read 14.7 psi. Humans do not feel this pressure because internal pressure of liquid in their bodies matches the external pressure. At sea level, Earth's atmosphere actually exerts a pressure of 14.7 psi. By contrast, psia measures pressure relative to a vacuum (such as that in space). ![]() Psig (pound-force per square inch gauge) is a unit of pressure relative to the surrounding atmosphere. MPa to psig, or enter any two units below: Enter two units to convert From: You can do the reverse unit conversion from
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