Difference in the matrix components by cleanup methods between the notified multiresidue pesticide analysis method in Japan and the QuEChERS method

Several validated methods exist for the quantitation of antibiotics in seafood with ultra-high pressure liquid chromatography coupled with tandem spectrometry (UPLC-MS/MS). To our knowledge, none have explored the effects of co-eluting matrix components on the accuracy of quantitation. Such matrix effects could disproportionally change the ionization of analytes and their respective surrogate/internal standards during UPLC-MS/MS analysis, resulting in over- or under-estimation of antibiotic values. In this study, we measured matrix effects, alongside extraction recoveries for 30 antibiotics and their respective class-specific surrogate standards in Sockeye, King and Ivory (non-pigmented) salmon extracted using the QUEChERS method. A modified QUEChERS method involving dispersive or hydrophilic-lipophilic balance (HLB) solid phase extraction (SPE) was also tested on Sockeye salmon. Despite acceptable extraction recoveries for most antibiotics extracted using the QUEChERS method, significant matrix effects were observed for most antibiotic standards. Dispersive or HLB SPE clean-up did not improve analyte recoveries from Sockeye salmon, and in some cases, increased matrix effects. Accuracy and sensitivity were reduced when matrix effects were high. Our results demonstrate that matrix components in salmon cause matrix effects on antibiotics during UPLC-MS/MS analysis which could impact the accuracy and sensitivity of the analysis.

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Pesticide residues in daily bee pollen samples (April–July) from an intensive agricultural region in Southern Germany

Environmental Science and Pollution Research ◽

10.1007/s11356-020-12318-2 ◽

2021 ◽

Author(s):

Carolin Friedle ◽

Klaus Wallner ◽

Peter Rosenkranz ◽

Dieter Martens ◽

Walter Vetter

Keyword(s):

Honey Bees ◽

Pesticide Residues ◽

Hazard Quotient ◽

Agricultural Landscapes ◽

Pesticide Analysis ◽

Analysis Method ◽

Southern Germany ◽

Serial Data ◽

Fruit Growing ◽

Insight Into

AbstractInsect-pollinated plants are essential for honey bees to feed their brood. In agricultural landscapes, honey bees and other pollinators are often exposed to pesticides used for cultivation. In order to gain more insight into the fluctuation of pesticide loads, 102 daily pollen samples were collected between April and July 2018 in a fruit-growing area in Southern Germany. Samples were analyzed with respect to more than 260 pesticides using a multi-residue pesticide analysis method. Almost 90% of the analyzed pollen samples featured between one and thirteen different pesticides. In total, 29 pesticides were detected at maximum concentrations of up to 4500 ng/g pollen. Maximum residual concentrations of most pesticides were observed during April and the first half of May, as well as during the second half of June. In most cases, serial data of pesticide residuals were detected for approximately 10 subsequent days with two or three maximum values, which were several folds higher than concentrations on the days before and thereafter. The pollen hazard quotient (PHQ) was calculated to estimate the risk of the detected pesticides to honey bees and wild pollinators.

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Dilution of QuEChERS Extracts Without Cleanup Improves Results in the UHPLC-MS/MS Multiresidue Analysis of Pesticides in Tomato

Food Analytical Methods ◽

10.1007/s12161-020-01921-1 ◽

2021 ◽

Author(s):

Fabiane M. Stringhini ◽

Lucila C. Ribeiro ◽

Graziela I. Rocha ◽

Juliana D. de B. Kuntz ◽

Renato Zanella ◽

...

Keyword(s):

Matrix Effect ◽

Practical Method ◽

Analysis Method ◽

Multiresidue Analysis ◽

Limit Of Quantification ◽

Chromatography Tandem Mass Spectrometry ◽

The Matrix ◽

Liquid Chromatography Tandem Mass ◽

Ultrahigh Performance Liquid Chromatography ◽

Positive Results

AbstractTomato is well-known to be one of the most cultivated and consumed vegetables worldwide and frequently contain pesticide residues. Therefore, a simple multiresidue method was established and validated to determine 129 pesticides and metabolites in tomato samples using a modified acetate QuEChERS without cleanup for sample preparation and determination by ultrahigh-performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS). Dilution of the raw extract in different proportions of mobile phase was evaluated and a dilution of 10 times presented adequate results improving analysis performance while minimizing the matrix effect. Validation performed according to SANTE guideline presented satisfactory results. Practical method limit of quantification was 0.01 mg kg−1 for most compounds. Recoveries between 70 and 120% with precision ≤ 20% were found for most compounds and spike levels evaluated. Matrix effect results were not significant for most part of compounds. Method proved to be simple, robust, and effective to be applied in routine analysis. Method applicability was performed by analysis of samples commercialized in Brazil and positive results were found demonstrating the importance of the proposed method.

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The inflammatory macrophage: a story of Jekyll and Hyde

Clinical Science ◽

10.1042/cs1040027 ◽

2002 ◽

Vol 104 (1) ◽

pp. 27-38 ◽

Cited By ~ 156

Author(s):

Jeremy S. DUFFIELD

Keyword(s):

Apoptotic Cells ◽

Tissue Healing ◽

Immune Mediated ◽

Selective Depletion ◽

The Matrix ◽

Matrix Components ◽

The Right ◽

Extracellular Structures ◽

Two Populations ◽

Inflammatory Macrophage

Recent investigations have highlighted new roles for the macrophage (Mϕ) in the biology of inflammation. Selective depletion of Mϕs from inflamed sites has confirmed their predominant role in immune-mediated damage. The components of this injury have been dissected. Mϕs mediate death of stromal, parenchymal and other immune cells by engaging the death programme, resulting in apoptosis. In addition, Mϕs induce destruction of matrix and extracellular structures both directly and indirectly by inducing stromal cells to release matrix metalloproteinases. However, there is another side to the inflammatory Mϕ. Evidence is provided that Mϕs at the same sites possess the ability to aid cell proliferation, secrete and stabilize new matrix components and induce resident cells to secrete matrix components themselves. Mϕ phagocytosis of apoptotic cells brings about a change from the cell-killing matrix-degrading cell to the matrix-generating cell-proliferating tissue-healing cell. Just as both Mϕ types are necessary at the inflamed site, the right balance of these two populations is required for healing and resolution. Evidence of excessive inflammation as a manifestation of impaired phagocytosis of apoptotic cells emphasizes that defects in the transition from one Mϕ type to another may account for the uncontrolled excessive inflammation seen in disease. Recent insights into the mechanisms by which apoptotic cells signal the change of function to the Mϕ offer the prospect of novel targets for manipulation of Mϕs in the inflamed tissue.

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