Name: analysis of organochlorine pesticides in a soil sample by a modified quechers approach using ammonium formate
Uploaded: 2023-01-20T14:00:00
Description: Watch this Scientific Journal Video about Analysis of Organochlorine Pesticides in a Soil Sample by a Modified QuEChERS Approach Using Ammonium Formate at JoVE.com

Jeg vil gerne takke Javier Hernández-Borges og Cecilia Ortega-Zamora for deres uvurderlige støtte. Jeg vil også gerne takke Universidad EAN og Universidad de La Laguna.

1. Fremstilling af stamopløsningerne
BEMÆRK: Det anbefales at bære nitrilhandsker, en laboratoriefrakke og sikkerhedsbriller under hele protokollen.
<ol><li>Der fremstilles en stamopløsning i acetone ved 400 mg/l fra en kommerciel blanding af OCP'er (se materialetabellen) ved 2.000 mg/l i hexan:toluen (1:1) i en 25 ml målekolbe. Tabel 1 viser hvert af de udvalgte OLT'er.</li>
	<li>De efterfølgende stamopløsninger fremstilles i acetone...

<ol>
	<li>Sabzevari, S., Hofman, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+worldwide+review+of+currently+used+pesticides'+monitoring+in+agricultural+soils.">A worldwide review of currently used pesticides' monitoring in agricultural soils.</a> Science of The Total Environment. 812, 152344 (2022).</li><li>Tzanetou, E. N., Karasali, H. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Comprehensive+review+of+organochlorine+pesticide+monitoring+in+agricultural+soils:+The+silent+threat+of+a+conventional+agricultural+past.">Comprehensive review of organochlorine pesticide monitoring in agricultural soils: The silent threat of a conventional agricultural past.</a> Agriculture. 12 (5), 728 (2022).</li><li>Farenhorst, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Importance+of+soil+organic+matter+fractions+in+soil-landscape+and+regional+assessments+of+pesticide+sorption+and+leaching+in+soil.">Importance of soil organic matter fractions in soil-landscape and regional assessments of pesticide sorption and leaching in soil.</a> Soil Science Society of America Journal. 70 (3), 1005-1012 (2006).</li><li>Silva, V., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Pesticide+residues+in+European+agricultural+soils+-+A+hidden+reality+unfolded.">Pesticide residues in European agricultural soils - A hidden reality unfolded.</a> Science of The Total Environment. 653, 1532-1545 (2019).</li><li>Vischetti, C., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Sub-lethal+effects+of+pesticides+on+the+DNA+of+soil+organisms+as+early+ecotoxicological+biomarkers.">Sub-lethal effects of pesticides on the DNA of soil organisms as early ecotoxicological biomarkers.</a> Frontiers in Microbiology. 11, 1892 (2020).</li><li>Alengebawy, A., Abdelkhalek, S. T., Qureshi, S. R., Wang, M. -. Q. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Heavy+metals+and+pesticides+toxicity+in+agricultural+soil+and+plants:+Ecological+risks+and+human+health+implications.">Heavy metals and pesticides toxicity in agricultural soil and plants: Ecological risks and human health implications.</a> Toxics. 9 (3), 42 (2021).</li><li>Zikankuba, V. L., Mwanyika, G., Ntwenya, J. E., James, A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Pesticide+regulations+and+their+malpractice+implications+on+food+and+environment+safety.">Pesticide regulations and their malpractice implications on food and environment safety.</a> Cogent Food &amp; Agriculture. 5 (1), 1601544 (2019).</li><li>Varela-Mart&#237;nez, D. A., Gonz&#225;lez-S&#225;lamo, J., Gonz&#225;lez-Curbelo, M. &. #. 1. 9. 3. ;., Hern&#225;ndez-Borges, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Quick,+Easy,+Cheap,+Effective,+Rugged+and+Safe+(QuEChERS)+extraction.">Quick, Easy, Cheap, Effective, Rugged and Safe (QuEChERS) extraction.</a> Handbooks in Separation Science. , 399-437 (2020).</li><li>Anastassiades, M., Lehotay, S. J., &#352;tajnbaher, D., Schenck, F. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Fast+and+easy+multiresidue+method+employing+acetonitrile+extraction/partitioning+and+&amp;#34;dispersive+solid-phase+extraction&amp;#34;+for+the+determination+of+pesticide+residues+in+produce.">Fast and easy multiresidue method employing acetonitrile extraction/partitioning and &amp;#34;dispersive solid-phase extraction&amp;#34; for the determination of pesticide residues in produce.</a> Journal of AOAC International. 86 (2), 412-431 (2003).</li><li>Gonz&#225;lez-Curbelo, M. &. #. 1. 9. 3. ;., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Evolution+and+applications+of+the+QuEChERS+method.">Evolution and applications of the QuEChERS method.</a> Trends in Analytical Chemistry. 71, 169-185 (2015).</li><li>European Union. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=European+Regulation+(EC)+NO+396/2005+of+the+European+Parliament+and+of+the+Council+of+23+February+2005+on+maximum+residue+levels+of+pesticides+in+or+on+food+and+feed+of+plant+and+animal+origin+and+amending+Council+Directive+91/414/EEC.">European Regulation (EC) NO 396/2005 of the European Parliament and of the Council of 23 February 2005 on maximum residue levels of pesticides in or on food and feed of plant and animal origin and amending Council Directive 91/414/EEC.</a> Official Journal of the European Union. 70, 1-16 (2005).</li><li>Kwon, H., Lehotay, S. J., Geis-Asteggiante, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Variability+of+matrix+effects+in+liquid+and+gas+chromatography-mass+spectrometry+analysis+of+pesticide+residues+after+QuEChERS+sample+preparation+of+different+food+crops.">Variability of matrix effects in liquid and gas chromatography-mass spectrometry analysis of pesticide residues after QuEChERS sample preparation of different food crops.</a> Journal of Chromatography A. 1270, 235-245 (2012).</li><li>Lehotay, S. J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Determination+of+pesticide+residues+in+foods+by+acetonitrile+extraction+and+partitioning+with+magnesium+sulfate:+Collaborative+study.">Determination of pesticide residues in foods by acetonitrile extraction and partitioning with magnesium sulfate: Collaborative study.</a> Journal of AOAC International. 90 (2), 485-520 (2007).</li><li>European Committee for Standardization (CEN). <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Standard+Method+EN+15662.+Food+of+plant+origin-Determination+of+pesticide+residues+using+GC-MS+and/or+LC-MS/MS+following+acetonitrile+extraction/partitioning+and+clean-up+by+dispersive+SPE-QuEChERS+method.">Standard Method EN 15662. Food of plant origin-Determination of pesticide residues using GC-MS and/or LC-MS/MS following acetonitrile extraction/partitioning and clean-up by dispersive SPE-QuEChERS method.</a> European Committee for Standardization. , (2008).</li><li>Gonz&#225;lez-Curbelo, M. &. #. 1. 9. 3. ;., Lehotay, S. J., Hern&#225;ndez-Borges, J., Rodr&#237;guez-Delgado, M. &. #. 1. 9. 3. ;. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Use+of+ammonium+formate+in+QuEChERS+for+high-throughput+analysis+of+pesticides+in+food+by+fast,+low-pressure+gas+chromatography+and+liquid+chromatography+tandem+mass+spectrometry.">Use of ammonium formate in QuEChERS for high-throughput analysis of pesticides in food by fast, low-pressure gas chromatography and liquid chromatography tandem mass spectrometry.</a> Journal of Chromatography A. 1358, 75-84 (2014).</li><li>Han, L., Sapozhnikova, Y., Lehotay, S. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Method+validation+for+243+pesticides+and+environmental+contaminants+in+meats+and+poultry+by+tandem+mass+spectrometry+coupled+to+low-pressure+gas+chromatography+and+ultrahigh-performance+liquid+chromatography.">Method validation for 243 pesticides and environmental contaminants in meats and poultry by tandem mass spectrometry coupled to low-pressure gas chromatography and ultrahigh-performance liquid chromatography.</a> Food Control. 66, 270-282 (2016).</li><li>Lehotay, S. J., Han, L., Sapozhnikova, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Automated+mini-column+solid-phase+extraction+clean-up+for+high-throughput+analysis+of+chemical+contaminants+in+foods+by+low-pressure+gas+chromatography-tandem+mass+spectrometry.">Automated mini-column solid-phase extraction clean-up for high-throughput analysis of chemical contaminants in foods by low-pressure gas chromatography-tandem mass spectrometry.</a> Chromatographia. 79 (17), 1113-1130 (2016).</li><li>Lehotay, S. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Possibilities+and+limitations+of+isocratic+fast+liquid+chromatography-tandem+mass+spectrometry+analysis+of+pesticide+residues+in+fruits+and+vegetables.">Possibilities and limitations of isocratic fast liquid chromatography-tandem mass spectrometry analysis of pesticide residues in fruits and vegetables.</a> Chromatographia. 82 (1), 235-250 (2019).</li><li>Han, L., Matarrita, J., Sapozhnikova, Y., Lehotay, S. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Evaluation+of+a+recent+product+to+remove+lipids+and+other+matrix+co-extractives+in+the+analysis+of+pesticide+residues+and+environmental+contaminants+in+foods.">Evaluation of a recent product to remove lipids and other matrix co-extractives in the analysis of pesticide residues and environmental contaminants in foods.</a> Journal of Chromatography A. 1449, 17-29 (2016).</li><li>Varela-Mart&#237;nez, D. A., Gonz&#225;lez-Curbelo, M. &. #. 1. 9. 3. ;., Gonz&#225;lez-S&#225;lamo, J., Hern&#225;ndez-Borges, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Analysis+of+pesticides+in+cherimoya+and+gulupa+minor+tropical+fruits+using+AOAC+2007.1+and+ammonium+formate+QuEChERS+versions:+A+comparative+study.">Analysis of pesticides in cherimoya and gulupa minor tropical fruits using AOAC 2007.1 and ammonium formate QuEChERS versions: A comparative study.</a> Microchemical Journal. 157, 104950 (2020).</li><li>Gonz&#225;lez-Curbelo, M. &. #. 1. 9. 3. ;., Varela-Mart&#237;nez, D. A., Ria&#241;o-Herrera, D. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Pesticide-residue+analysis+in+soils+by+the+QuEChERS+method:+A+review.">Pesticide-residue analysis in soils by the QuEChERS method: A review.</a> Molecules. 27 (13), 4323 (2022).</li><li>Anastassiades, M., Ma&#353;tovsk&#225;, K., Lehotay, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Evaluation+of+analyte+protectants+to+improve+gas+chromatographic+analysis+of+pesticides.">Evaluation of analyte protectants to improve gas chromatographic analysis of pesticides.</a> Journal of Chromatography A. 1015 (1-2), 163-184 (2003).</li><li>Ma&#353;tovsk&#225;, K., Lehotay, S., Anastassiades, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Combination+of+analyte+protectants+to+overcome+matrix+effects+in+routine+GC+analysis+of+pesticide+residues+in+food+matrixes.">Combination of analyte protectants to overcome matrix effects in routine GC analysis of pesticide residues in food matrixes.</a> Analytical Chemistry. 77 (24), 8129-8137 (2005).</li><li>Rahman, M., Abd El-Aty, A., Shim, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Matrix+enhancement+effect:+A+blessing+or+a+curse+for+gas+chromatography?+-+A+review.">Matrix enhancement effect: A blessing or a curse for gas chromatography? - A review.</a> Analytica Chimica Acta. 801, 14-21 (2013).</li><li>Rouvire, F., Bulet&#233;, A., Cren-Oliv&#233;, C., Arnaudguilhem, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Multiresidue+analysis+of+aromatic+organochlorines+in+soil+by+gas+chromatography-mass+spectrometry+and+QuEChERS+extraction+based+on+water/dichloromethane+partitioning.+Comparison+with+accelerated+solvent+extraction.">Multiresidue analysis of aromatic organochlorines in soil by gas chromatography-mass spectrometry and QuEChERS extraction based on water/dichloromethane partitioning. Comparison with accelerated solvent extraction.</a> Talanta. 93, 336-344 (2012).</li><li>Lesueur, C., Gartner, M., Mentler, A., Fuerhacker, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Comparison+of+four+extraction+methods+for+the+analysis+of+24+pesticides+in+soil+samples+with+gas+chromatography-mass+spectrometry+and+liquid+chromatography-ion+trap-mass+spectrometry.">Comparison of four extraction methods for the analysis of 24 pesticides in soil samples with gas chromatography-mass spectrometry and liquid chromatography-ion trap-mass spectrometry.</a> Talanta. 75 (1), 284-293 (2008).</li><li>&#208;urovi&#263;-Pej&#269;ev, R. D., Bursi&#263;, V. P., Zeremski, T. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Comparison+of+QuEChERS+with+traditional+sample+preparation+methods+in+the+determination+of+multiclass+pesticides+in+soil.">Comparison of QuEChERS with traditional sample preparation methods in the determination of multiclass pesticides in soil.</a> Journal of AOAC International. 102 (1), 46-51 (2019).</li><li>European Commission. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=SANTE/11312/2021.+Guidance+document+on+analytical+quality+control+and+method+validation+procedures+for+pesticide+residues+analysis+in+food+and+feed.">SANTE/11312/2021. Guidance document on analytical quality control and method validation procedures for pesticide residues analysis in food and feed.</a> European Commission. , (2021).</li></ol>

Den originale9 og de to officielle versioner13,14 af QuEChERS-metoden bruger magnesiumsulfat sammen med natriumchlorid-, acetat- eller citratsalte til at fremme adskillelse af acetonitril/vandblanding under ekstraktion. Imidlertid har disse salte tendens til at blive deponeret som faste stoffer på overfladerne i massespektrometrikilden (MS), hvilket medfører behovet for øget vedligeholdelse af væskekromatografi (LC)-MS-baserede metoder...

Behovet for at øge fødevareproduktionen har ført til intensiv og udbredt anvendelse af pesticider på verdensplan i løbet af de sidste par årtier. Pesticider påføres afgrøderne for at beskytte dem mod skadedyr og øge afgrødeudbyttet, men deres rester ender normalt i jordmiljøet, især i landbrugsområder1. Desuden har nogle pesticider, såsom organiske chlorpesticider (OCP'er), en meget stabil struktur, så deres rester nedbrydes ikke let og forbliver i jorden i lang tid2. Generelt har jorden en høj kapacitet til at akkumulere pesticidrester, især når den har et højt indhold af organisk materiale3. Som følge heraf er jorden et af de miljørum, der er mest forurenet med pesticidrester. F.eks. viste en af de fuldstændige undersøgelser til dato, at 83 % af 317 landbrugsjorder i hele EU var forurenet med en eller flere pesticidrester4. 
Jordforurening med pesticidrester kan påvirke ikke-målarter, jordfunktion og forbrugersundhed gennem fødekæden på grund af restkoncentrationernes høje toksicitet 5,6. Det er derfor vigtigt at evaluere pesticidrester i jorden for at vurdere deres potentielle negative virkninger på miljøet og menneskers sundhed, navnlig i udviklingslandene på grund af mangel på strenge regler for anvendelsen af pesticider7. Dette gør analyse af pesticidrester stadig vigtigere. Hurtig og nøjagtig analyse af pesticidrester i jorden er imidlertid en vanskelig udfordring på grund af det store antal interfererende stoffer samt disse analysanders lave koncentrationsniveau og forskellige fysisk-kemiske egenskaber4.
Af alle metoderne til analyse af pesticidrester er QuEChERS-metoden blevet den hurtigste, nemmeste, billigste, mest effektive, robuste og sikreste mulighed8. QuEChERS-metoden involverer to trin. I det første trin udføres en mikroskalaekstraktion baseret på opdeling via saltning mellem et vandigt og et acetonitrillag. I det andet trin udføres en rengøringsproces under anvendelse af en dispersiv fastfaseekstraktion (dSPE); denne teknik bruger små mængder af flere kombinationer af porøse sorbenter til at fjerne matrixinterfererende komponenter og overvinder ulemperne ved konventionel SPE9. Derfor er QuEChERS en miljøvenlig tilgang med lidt opløsningsmiddel/kemikalie, der går til spilde, der giver meget nøjagtige resultater og minimerer potentielle kilder til tilfældige og systematiske fejl. Faktisk er det blevet anvendt med succes til rutinemæssig analyse med høj kapacitet af hundredvis af pesticider med stærk anvendelighed i næsten alle typer miljø-, landbrugsfødevare- og biologiske prøver 8,10. Dette arbejde sigter mod at anvende og validere en ny modifikation af QuEChERS-metoden, der tidligere blev udviklet og koblet til GC-MS for at analysere OCP'er i landbrugsjord.

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>15 mL disposable glass conical centrifuge tubes</td>
			<td>PYREX</td>
			<td>99502-15</td>
			<td></td>
		</tr>
		<tr>
			<td>2 mL centrifuge tubes</td>
			<td>Eppendorf</td>
			<td>30120094</td>
			<td></td>
		</tr>
		<tr>
			<td>50 mL centrifuge tubes with screw caps</td>
			<td>VWR</td>
			<td>21008-169</td>
			<td></td>
		</tr>
		<tr>
			<td>5977B mass-selective detector</td>
			<td>Agilent Technologies</td>
			<td>1617R019</td>
			<td></td>
		</tr>
		<tr>
			<td>7820A gas chromatography system</td>
			<td>Agilent Technologies</td>
			<td>16162016</td>
			<td></td>
		</tr>
		<tr>
			<td>Acetone</td>
			<td>Supelco</td>
			<td>1006582500</td>
			<td></td>
		</tr>
		<tr>
			<td>Acetonitrile</td>
			<td>VWR</td>
			<td>83642320</td>
			<td></td>
		</tr>
		<tr>
			<td>Ammonium formate</td>
			<td>VWR</td>
			<td>21254260</td>
			<td></td>
		</tr>
		<tr>
			<td>Automatic shaker KS 3000 i control</td>
			<td>IKA</td>
			<td>3940000</td>
			<td></td>
		</tr>
		<tr>
			<td>Balance</td>
			<td>Sartorius Lab Instruments Gmbh &#38; Co</td>
			<td>ENTRIS224I-1S</td>
			<td></td>
		</tr>
		<tr>
			<td>Bondesil-C18, 40 &#181;m</td>
			<td>Agilent Technologies</td>
			<td>12213012</td>
			<td></td>
		</tr>
		<tr>
			<td>Bondesil-PSA, 40 &#181;m</td>
			<td>Agilent Technologies</td>
			<td>12213024</td>
			<td></td>
		</tr>
		<tr>
			<td>Cyclohexane</td>
			<td>VWR</td>
			<td>85385320</td>
			<td></td>
		</tr>
		<tr>
			<td>EPA TCL pesticides mix</td>
			<td>Sigma Aldrich</td>
			<td>48913</td>
			<td></td>
		</tr>
		<tr>
			<td>Ethyl acetate</td>
			<td>Supelco</td>
			<td>1036492500</td>
			<td></td>
		</tr>
		<tr>
			<td>G4567A automatic sampler</td>
			<td>Agilent Technologies</td>
			<td>19490057</td>
			<td></td>
		</tr>
		<tr>
			<td>HP-5ms Ultra Inert (5%-phenyl)-methylpolysiloxane 30 m x 250 &#181;m x 0.25 &#181;m column</td>
			<td>Agilent Technologies</td>
			<td>19091S-433UI</td>
			<td></td>
		</tr>
		<tr>
			<td>Magnesium sulfate monohydrate</td>
			<td>Sigma Aldrich</td>
			<td>434183-1KG</td>
			<td></td>
		</tr>
		<tr>
			<td>Mega Star 3.R centrifuge</td>
			<td>VWR</td>
			<td>521-1752</td>
			<td></td>
		</tr>
		<tr>
			<td>Milli-Q gradient A10</td>
			<td>Millipore</td>
			<td>RR400Q101</td>
			<td></td>
		</tr>
		<tr>
			<td>p,p&#39;-DDE-d8</td>
			<td>Dr Ehrenstorfer</td>
			<td>DRE-XA12041100AC</td>
			<td></td>
		</tr>
		<tr>
			<td>Pipette tips 2 - 200 &#181;L</td>
			<td>BRAND</td>
			<td>732008</td>
			<td></td>
		</tr>
		<tr>
			<td>Pipette tips 5 mL</td>
			<td>BRAND</td>
			<td>702595</td>
			<td></td>
		</tr>
		<tr>
			<td>Pipette tips 50 - 1000 uL</td>
			<td>BRAND</td>
			<td>732012</td>
			<td></td>
		</tr>
		<tr>
			<td>Pippette Transferpette S variabel 10 - 100 &#181;L</td>
			<td>BRAND</td>
			<td>704774</td>
			<td></td>
		</tr>
		<tr>
			<td>Pippette Transferpette S variabel 100 - 1000 &#181;L</td>
			<td>BRAND</td>
			<td>704780</td>
			<td></td>
		</tr>
		<tr>
			<td>Pippette Transferpette S variabel 20 - 200 &#181;L</td>
			<td>BRAND</td>
			<td>704778</td>
			<td></td>
		</tr>
		<tr>
			<td>Pippette Transferpette S variabel 500 - 5000 &#181;L</td>
			<td>BRAND</td>
			<td>704782</td>
			<td></td>
		</tr>
		<tr>
			<td>Vials with fused-in insert</td>
			<td>Sigma Aldrich</td>
			<td>29398-U</td>
			<td></td>
		</tr>
		<tr>
			<td>OCPs</td>
			<td></td>
			<td>CAS registry number</td>
			<td></td>
		</tr>
		<tr>
			<td>&#945;-BHC</td>
			<td></td>
			<td>319-84-6</td>
			<td></td>
		</tr>
		<tr>
			<td>&#946;-BHC</td>
			<td></td>
			<td>319-85-7</td>
			<td></td>
		</tr>
		<tr>
			<td>Lindane</td>
			<td></td>
			<td>58-89-9</td>
			<td></td>
		</tr>
		<tr>
			<td>&#948;-BHC</td>
			<td></td>
			<td>319-86-8</td>
			<td></td>
		</tr>
		<tr>
			<td>Heptachlor</td>
			<td></td>
			<td>76-44-8</td>
			<td></td>
		</tr>
		<tr>
			<td>Aldrin</td>
			<td></td>
			<td>309-00-2</td>
			<td></td>
		</tr>
		<tr>
			<td>Heptachlor epoxide</td>
			<td></td>
			<td>1024-57-3</td>
			<td></td>
		</tr>
		<tr>
			<td>&#945;-Endosulfan</td>
			<td></td>
			<td>959-98-8</td>
			<td></td>
		</tr>
		<tr>
			<td>4,4&#39;-DDE-d8 (IS)</td>
			<td></td>
			<td>93952-19-3</td>
			<td></td>
		</tr>
		<tr>
			<td>4,4&#39;-DDE</td>
			<td></td>
			<td>72-55-9</td>
			<td></td>
		</tr>
		<tr>
			<td>Dieldrin</td>
			<td></td>
			<td>60-57-1</td>
			<td></td>
		</tr>
		<tr>
			<td>Endrin</td>
			<td></td>
			<td>72-20-8</td>
			<td></td>
		</tr>
		<tr>
			<td>&#946;-Endosulfan</td>
			<td></td>
			<td>33213-65-9</td>
			<td></td>
		</tr>
		<tr>
			<td>4,4&#39;-DDD</td>
			<td></td>
			<td>72-54-8</td>
			<td></td>
		</tr>
		<tr>
			<td>Endosulfan sulfate</td>
			<td></td>
			<td>1031-07-8</td>
			<td></td>
		</tr>
		<tr>
			<td>4,4&#39;-DDT</td>
			<td></td>
			<td>50-29-3</td>
			<td></td>
		</tr>
		<tr>
			<td>Endrin ketone</td>
			<td></td>
			<td>53494-70-5</td>
			<td></td>
		</tr>
		<tr>
			<td>Methoxychlor</td>
			<td></td>
			<td>72-43-5</td>
			<td></td>
		</tr>
	</tbody>
</table>

analysis of organochlorine pesticides in a soil sample by a modified quechers approach using ammonium formate

I øjeblikket repræsenterer QuEChERS-metoden den mest anvendte prøveforberedelsesprotokol på verdensplan til analyse af pesticidrester i en bred vifte af matricer både i officielle og ikke-officielle laboratorier. QuEChERS-metoden ved anvendelse af ammoniumformiat har tidligere vist sig at være fordelagtig sammenlignet med den originale og de to officielle versioner. På den ene side er den enkle tilsætning af 0,5 g ammoniumformiat pr. gram prøve tilstrækkelig til at inducere faseseparation og opnå god analytisk ydeevne. På den anden side reducerer ammoniumformiat behovet for vedligeholdelse i rutinemæssige analyser. Her blev en modificeret QuEChERS-metode ved anvendelse af ammoniumformiat anvendt til samtidig analyse af organiske chlorpesticidrester (OCP) i landbrugsjord. Specifikt blev 10 g af prøven hydreret med 10 ml vand og derefter ekstraheret med 10 ml acetonitril. Dernæst blev faseseparation udført under anvendelse af 5 g ammoniumformiat. Efter centrifugering blev supernatanten underkastet et dispergerende fastfaseekstraktionstrin med vandfrit magnesiumsulfat, primær-sekundær amin og octadecylsilan. Gaskromatografi-massespektrometri blev anvendt som analytisk teknik. QuEChERS-metoden ved anvendelse af ammoniumformiat demonstreres som et vellykket alternativ til ekstraktion af OCP-rester fra en jordprøve.

Den fulde validering af analysemetoden blev udført med hensyn til linearitet, matrixeffekter, genfinding og repeterbarhed.
Matrixmatchede kalibreringskurver med blindprøver med spids ved seks koncentrationsniveauer (5 μg/kg, 10 μg/kg, 50 μg/kg, 100 μg/kg, 200 μg/kg og 400 μg/kg) blev anvendt til linearitetsvurderingen. Bestemmelseskoefficienterne (R2) var højere end eller lig med 0,99 for alle OLT'erne. Det laveste kalibreringsniveau (LCL) blev fastsat til 5 μg/kg, hvilket...

Watch this Scientific Journal Video about Analysis of Organochlorine Pesticides in a Soil Sample by a Modified QuEChERS Approach Using Ammonium Formate at JoVE.com

Analysis of Organochlorine Pesticides in a Soil Sample by a Modified QuEChERS Approach Using Ammonium Formate

Denne protokol beskriver anvendelsen af ammoniumformiat til fasedeling i QuEChERS sammen med gaskromatografi-massespektrometri til vellykket bestemmelse af organiske chlorpesticidrester i en jordprøve.

Analyse af organiske chlorpesticider i en jordprøve ved en modificeret QuEChERS-tilgang under anvendelse af ammoniumformiat

Currently, the QuEChERS method represents the most widely used sample preparation protocol worldwide for analyzing pesticide residues in a broad variety ...

QuEChERS-metoden ved anvendelse af ammoniumformiat er et vellykket alternativ til originalen såvel som de to officielle versioner til ekstraktion af organiske chlorpesticider fra jordprøver. Tilsætningen af blot 0,5 gram ammoniumformiat pr. gram prøve er tilstrækkelig til at inducere faseadskillelse mellem vand- og acetonitrillagene og opnå god analytisk ydeevne. For at starte prøveforberedelsen vejes 10 gram af jordprøven i et 50 ml centrifugerør.Tilsæt 50 mikroliter af den interne standard eller IS-opløsning med en koncentration på 20 milligram pr. Liter til jordprøven for at opnå 100 mikrogram IS pr. Kg jord. Tilsæt 10 ml vand, og ryst røret ved hjælp af en automatiseret ryster ved 10 g i fem minutter. Derefter tilsættes 10 ml acetonitril, og ryst røret ved 10 g i fem minutter.Derefter tilsættes fem gram ammoniumformiat og rystes røret kraftigt i hånden i et minut, før det centrifugeres ved 1800 g i fem minutter. Til oprydning overføres en milliliter acetonitrilekstrakt til centrifugerøret indeholdende vandfrit magnesiumsulfat, primær sekundær amin og octadecylsilan ved dispersiv fastfaseekstraktion. Vortex røret i 30 sekunder, og centrifuger det ved 1800 g i fem minutter.Efter centrifugering overføres 200 mikroliter af ekstraktet til et passende mærket autosamplerhætteglas, forsynet med en 300 ml smeltet indsats, og der udføres en instrumentel analyse ved hjælp af et GC/MS-system. Der injiceres 1,5 mikroliter af prøven i et GC/MS-system med et enkelt quadrupolmassespektrometer ved hjælp af en autosampler ved 280 grader Celsius i splitløs tilstand. De undersøgte matrixeffektfordelinger for de undersøgte organiske chlorpesticider eller OCP'er viste både positive matrixeffektprocenter svarende til en signalforbedring såvel som negative procentdele svarende til signalundertrykkelse.Værdier mellem minus 20 og 20% indikerede en blød matrixeffekt, mens værdier mellem minus 20 og minus 50% og mellem 20 og 50% svarede til en medium matrixeffekt. En stærk matrixeffekt blev angivet med procentværdier højere end 50 eller lavere end minus 50. Evaluering af den samlede genvinding for alle pesticider ved forskellige spidsniveauer viste, at de fleste af de undersøgte OCP'er havde gennemsnitlige genvindingsprocenter på 70 til 120% og relative standardafvigelses- eller RSD-værdier lavere end 20%Heptachlor, endrin og beta-endosulfan havde imidlertid lidt højere gennemsnitlige genvindinger.Dette alternativ kan anvendes til analyse af pesticider af LC-MS, hvilket ville være endnu mere interessant, da ammoniumformiat er en hjælp til ionisering i positiv elektrosprayionisering.

Research

JoVE Journal

Chemistry

Untargeted Metabolomics from Biological Sources Using Ultraperformance Liquid Chromatography-High Resolution Mass Spectrometry (UPLC-HRMS)

Untargeted Metabolomics from Biological Sources Using Ultraperformance Liquid Chromatography-High Resolution Mass Spectrometry UPLC-HRMS

Målrettede Metabolomics fra biologiske kilder Brug Ultraperformance væskekromatografi-højopløsningsmassespektrometri (UPLC-HRMS)

Here we present a workflow to analyze the metabolic profiles for biological samples of interest including; cells, serum, or tissue. The sample is first ...

Covalent Binding of BMP-2 on Surfaces Using a Self-assembled Monolayer Approach

Kovalent binding af BMP-2 på overflader med en selv-samlet monolag Approach

Bone morphogenetic protein 2 (BMP-2) is a growth factor embedded in the extracellular matrix of bone tissue. BMP-2 acts as trigger of mesenchymal cell ...

Dependence of Laser-induced Breakdown Spectroscopy Results on Pulse Energies and Timing Parameters Using Soil Simulants

Afhængighed af Laser-induceret Fordeling spektroskopi Resultater på Pulse Energies og timing parametre ved hjælp Jord Simulanterne

The  dependence of some LIBS detection capabilities on lower pulse energies (&lt;100  mJ) and timing parameters were examined using synthetic silicate ...

An Inverse Analysis Approach to the Characterization of Chemical Transport in Paints

En omvendt analyse tilgang til karakterisering af kemiske Transport i Maling

The ability to directly characterize chemical transport and interactions that occur within a material (i.e., subsurface dynamics) is a vital component in ...

Electrochemically and Bioelectrochemically Induced Ammonium Recovery

Elektrokemisk og Bioelectrochemically Induceret Ammonium Recovery

Streams such as urine and manure can contain high levels of ammonium, which could be recovered for reuse in agriculture or chemistry. The extraction of ...

Transport of Surface-modified Carbon Nanotubes through a Soil Column

Transport af overflademodificeret kulstofnanorør gennem en Soil kolonne

Carbon nanotubes (CNTs) are widely manufactured nanoparticles, which are being utilized in a number of consumer products, such as sporting goods, ...

Ethylene Polymerizations Using Parallel Pressure Reactors and a Kinetic Analysis of Chain Transfer Polymerization

Ethylen Polymeriseringer Brug Parallel Pressure reaktorer og en Kinetic Analyse af Chain Transfer Polymerisation

We demonstrate a method for high-throughput catalyst screening using a parallel pressure reactor starting from the initial synthesis of a nickel ...

Glycan Node Analysis: A Bottom-up Approach to Glycomics

Glycan Node Analyse: en bottom-up tilgang til Glycomics

Synthesized in a non-template-driven process by enzymes called glycosyltransferases, glycans are key players in various significant intra- and ...

Rapid High-throughput Species Identification of Botanical Material Using Direct Analysis in Real Time High Resolution Mass Spectrometry

Hurtig High-throughput Arter Identifikation af Botanisk Materiale Brug Direct Analyse i Real Time High Resolution massespektrometri

We demonstrate that direct analysis in real time-high resolution mass spectrometry can be used to produce mass spectral profiles of botanical material, ...

The MPLEx Protocol for Multi-omic Analyses of Soil Samples

MPLEx protokol for Multi-omic analyser af jordprøver

Mass spectrometry (MS)-based integrated metaproteomic, metabolomic, and lipidomic (multi-omic) studies are transforming our ability to understand and ...