Page 11 - Shimadzu Journal vol.1
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Food safety                                                                         .                                                                   11









                                  LCMS-8040 triple quadrupole mass   spectrometer ESI-Positive and negative (15 msec. polarity    switch)  Dwell time 5 msec.  Pause time 1 msec.   250  o C  400  o C  15 L min -1  2 L min -1 1:1 water:methanol with 10 mM ammonium   acetate  Flow rate: 0.5mL min -1 Flow injection analysis (No column fitted) 0.2 μL (0.01 mg kg -1  pesticide standard     solution) Carrier 1:1 water:methanol  Flow rate: 0.3mL min -1 Flow injection analysis (No column fitted) 5 μL injection (0.01 mg kg -1  pesticide standard   solution)  1 μL air gap (see text for mobile phase compositions) Pesticide limits of detection were calculated based on the method  described by the US-EPA in Title 40 Code of Federal Regulation Part  136
















                              MS Parameters    MS:  Ionisation:  SRM:  Desolvation line:   Heating block:  Drying gas:   Nebulising gas:   SRM optimisation:  Mobile phase   screening:  interval:   (  =  analyses.   3. Results and discussion   3.1 SRM optimisation   transitions are shown in Table-1.








                                                                                   ʢ5ʙ200ppbʣ                                   Shim-pack XR-ODS III (150 x 2 mm, 2.2 µm   A = Water with 5 mM ammonium formate and   B = Methanol with 5 mM ammonium formate   B%  A%  5  95  100  0  100  0  5  95  5  95 32 µL (stacked injection: 2 µL sample + 30µL
                                                 In this work, we discuss the development of a multi-residue pesticide
                                                                addition to ensuring chromatographic resolution of pesticide isomers
                                     discussed pitfalls of GCMS, have meant LCMSMS has become a vital
                                                   method for 210 pesticides using the Nexera UHPLC and LCMS-8040
                                                          preparation. The method was evaluated in matrix to ensure that the
                                                              regulatory guidelines around the world with acceptable precision, in
                                 without the need for derivatisation. 9  Recent improvements in liquid
                                   chromatography - tandem mass spectrometry, combined with the
                                         selective and sensitive analysis and is well suited to the multi-class
                                                            necessary reporting limits were obtained according to the various
                                       technique. LC-triple quadruple mass spectrometry enables highly
                              be analysed in this way due to poor thermal stability or volatility
                                                     triple quadruple. Pesticides were matrix-matched in food matrix
                                                        (lettuce, pear and dried fruit) following QuEChERS sample
                                            analysis of large numbers of pesticides at trace levels.
                                                                   with identical SRM transitions.    2. Experimental  A stock of pesticides was obtained from the Food and Environment  Agency, UK, at a concentration of 0.01 mg kg -1  (for each pesticide) in  acetone:acetonitrile 1:1. Linearity was investigated over a nine-point  calibration with samples ranging from 0.005ʙ0.2mgkg-1 analysed in duplicate; calibration samples were injected once in  increasing order and once in decreasing order. Linearity was assessed  with four calibration curves prepared by serial dilution of: (1)  acetonitrile, (2) dried fruit extract, (3) lettuce extract and, (4) pear  extract. Instrumental area repeatability was determined by replicate  (n=6) injection

























                                                                                                                      published national standard GB 2763-2005 in 2005 and more recently
                                                                          analysis turnaround times, and all the while maintaining or reducing costs. In this study a method was successfully developed for the quantitation
                                                                                   reporting level was typically less than 5 %RSD for compounds and correlation coefficients were typically greater than 0.997 in a variety of studied
                                                                                                                  system for agricultural chemical residues in foods, introduced in 2006,
                                                   Dr. Simon Hird from the Food and Environment Research Agency (FERA) in York
                                                                            of 210 commonly analysed pesticides in food samples using the Nexera UHPLC and LCMS-8040. Initial validation was performed to demonstrate
                                                                                                                    contains MRLs for over 400 pesticides in various commodities. 6  China
                                                                        laboratories under increasing pressure to expand the list of targeted pesticides, detect analytes at lower levels and with greater precision, reduce
                                                                                     food extracts. Consequently, the LCMS-8040 is ideally suited for routine monitoring of pesticides below the 0.01 mg kg -1  default level set by EU
                                                                                                             Regulations (US Environmental Protection Agency Office of Pesticide
                                                                   Pesticides and their metabolites are of great concern to society as they are harmful to human health, pollute natural resources and disturb the
                                                                              instrument capabilities. Limits of detection (LOD) for 90 % of compounds were less than 0.001 mg kg-1 (1 ppb) and all compounds were less
                                                                                                     even lower MRLs for a few other very toxic pesticides. 4  Regulatory
                                                                                                         guidelines. In the US, tolerances for more than 450 pesticides and
                                                                     equilibrium of the ecosystem. Consequently, stricter food safety regulations are being enforced around the world, placing pesticide analysis
                                                                                than 0.01 mg kg -1  (10 ppb) for both the quantifying and qualifying transitions using only a 2 µL injection. Repeatability at the 0.01 mg kg -1
                                                                                                                Programs) and are enforced by the US FDA. 5  Japan’s positive list
                                                                                                       bodies around the world, as in the EU, have produced similar
                                                                                                           other ingredients are stated in the electronic Code of Federal
                                             David R. Baker 1 , Chris Titman 1 , Alan J. Barnes 1 , Neil J. Loftus 1 , Alexander Mastoroudes 2 , Simon Hird 3
                                                                                                                           MRLS for 85 pesticides in food. 7,8   GB 28260-2011 which was introduced in 2012 and specifies 181  Consequently, pesticide analysis laboratories are under increasing  pressure to expand the list of targeted pesticides, detect analytes at  lower levels and with greater precision, reduce analysis turnaround  times and reduce usage of hazardous solvents while maintaining or  reducing costs. Pesticide residues were traditionally analysed mainly by  GC-based multi-residue methods often with MS detection. However,  many modern  (semi)polar compounds and/or ionic compounds could not

























          global w430×h280        Multi-Residue Analysis of 210 Pesticides in Food Samples by Triple Quadrupole UHPLC-MS/MS    1 Shimadzu Corporation, Manchester, UK 2 Kings College London, London, UK 3 Food and Environment Research Agency, York, UK   and Japanese legislation.  Keywords : Pesticides; Multi-residue analysis; LCMS-8040; Food safety; Fruit; Vegetables   Pesticide residues in food continue to be the target of studies due to  the uncertainty concerning adverse effects that those residues may  have on human health after a lengthy exposure at low levels. More  than 1000 active ingredients have been utilised and are formulated in  thousands of different commercial products. They include a variety of  compounds, mainly insecticide








                     Food safety                                Abstract                         1. Introduction                   pesticide. 2                             10
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