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Liquid Chromatography
Most chemical analysis methods require shaking samples to properly homogenise samples and/or perform analyte extraction processes. The application of conventional shaking systems does not always result in adequate homogenisation and/or analyte extraction. The axial oscillating shaking of Agytax® advantageously substitutes the process performed manually until now, eliminating problems of reproducibility and repeatability. This problem is accentuated even more when there is a need to shake a large number of samples simultaneously. Automation of these steps significantly reduces the standard deviation coefficient of a chromatographic method.
This diagram describes an extraction method for the analysis of residue in plant samples, which was developed by the Community Reference Laboratory (Universidad de Almería) and is optimised through the use of Agytax®. The buffered QuEChERS method was used (Lehotay et al.: Journal of AOAC International Vol. 88, No. 2, 2005). The results of the analysis using liquid chromatography coupled with tandem mass spectrometry are shown in the table below, which also indicates the recovery percentages for each analyte.
| Pesticide | R | (V.C) | Pesticide | R | (V.C) | Pesticide | R | (V.C) |
|---|---|---|---|---|---|---|---|---|
| Acetamiprid | 102.0 | 3.4 | Diflubenzuron | 94.3 | 2.4 | Monocrotophos | 91.3 | 4.7 |
| Aclonifen | 82.9 | 3.9 | Dimethomorph | 83.6 | 2.0 | Monolinuron | 77.0 | 3.2 |
| Albendazole | 78.6 | 3.0 | Edifenphos | 91.9 | 4.4 | Monuron | 98.7 | 1.6 |
| Aldicarb | 102.7 | 2.4 | Emama. benzoate | 92.5 | 5.8 | Nitempyram | 101.2 | 3.1 |
| Aldicarb sulfone | 108.9 | 3.9 | Ethiofencarb | 92.0 | 1.6 | Omethoate | 95.4 | 2.2 |
| Aldicarb sulfoxide | 101.7 | 2.2 | Ethion | 88.2 | 8.4 | Oxadixyl | 95.6 | 1.9 |
| Anilofos | 94.6 | 2.5 | Ethiprole | 105.9 | 3.4 | Oxamyl | 94.8 | 3.4 |
| Atrazine | 76.6 | 9.3 | Fenamiphos | 92.1 | 2.6 | Penconazole | 115.9 | 6.4 |
| Azinphos-ethyl | 99.7 | 3.0 | Fenarimol | 89.5 | 4.9 | Pirimiphos-methyl | 80.8 | 5.4 |
| Azoxystrobin | 96.9 | 3.9 | Fenhexamid | 102.5 | 2.4 | Prochloraz | 121.0 | 0.7 |
| Bendiocarb | 95.0 | 2.7 | Fenobucarb | 88.0 | 2.2 | Procymidone | 93.3 | 2.2 |
| Bromacil | 92.0 | 3.2 | Fenoxycarb | 91.2 | 2.4 | Propamocarb | 78.6 | 6.0 |
| Bromuconazole | 87.8 | 2.5 | Fenuron | 77.1 | 5.8 | Propargite | 65.5 | 8.3 |
| Bupirimate | 110.3 | 9.7 | Fipronil | 92.6 | 0.9 | Propazine | 68.7 | 3.6 |
| Buprofezin | 82.5 | 2.8 | Flazasulfuron | 87.3 | 1.6 | Pyridaben | 93.2 | 0.9 |
| Butocarboxin | 100.2 | 5.6 | Fluacrypyrim | 98.2 | 2.7 | Pyridaphenthion | 85.1 | 4.5 |
| Butoxycarboxin | 90.3 | 3.9 | Fluazifop | 78.9 | 2.2 | Pyrimethanil | 87.3 | 3.9 |
| Cambendazole | 102.5 | 3.7 | Fluometuron | 88.3 | 1.9 | Spinosyn A | 85.1 | 4.5 |
| Carbaryl | 98.4 | 1.3 | Fluquinconazole | 111.1 | 2.8 | Spinosyn D | 92.5 | 3.0 |
| Carbendazim | 76.0 | 4.9 | Fluroxypyr | 96.3 | 6.7 | Spiromesifen | 77.6 | 2.1 |
| Carbofuran | 92.7 | 8.4 | Hexaflumuron | 96.0 | 3.9 | Spiroxamine | 98.0 | 1.0 |
| Chlorbromuron | 97.6 | 2.7 | Hexythiazox | 76.5 | 6.7 | Tebufenozide | 82.3 | 2.0 |
| Chlorfenvinphos | 90.5 | 1.8 | Indoxacarb | 89.3 | 2.0 | Tebufenpyrad | 94.3 | 3.0 |
| Chloridazon | 98.4 | 3.6 | Iprodione | 96.2 | 4.8 | Teflubenzuron | 86.4 | 1.6 |
| Chlorotoluron | 94.4 | 3.4 | Isocarbofos | 93.6 | 2.0 | Terbuthylazine | 118.2 | 3.6 |
| Chromafenozide | 70.7 | 5.8 | Isofenfos Metil | 103.8 | 4.1 | Terbutrin | 75.9 | 4.8 |
| Clofentezine | 79.0 | 7.4 | Isoprocarb | 103.1 | 2.1 | Thiabendazole | 90.6 | 2.5 |
| Cymoxanil | 77.5 | 6.4 | Isoproturon | 90.0 | 2.4 | Thiacloprid | 89.3 | 3.2 |
| Cyproconazole | 85.3 | 7.8 | Kresoxim-methyl | 91.0 | 2.4 | Thiametoxam | 91.1 | 1.7 |
| Cyromazine | 83.9 | 2.4 | Lenacil | 96.8 | 2.2 | Thiocyclam | 88.8 | 3.1 |
| Deet | 87.9 | 0.6 | Linuron | 92.5 | 7.2 | Tolfenpyrad | 91.3 | 1.1 |
| Demethon-D-methyl | 92.2 | 1.9 | Malathion | 66.8 | 3.8 | Triadimefon | 64.0 | 4.7 |
| Desethylterbutylazine | 82.9 | 8.9 | Mebendazole | 77.0 | 3.2 | Triadimenol | 83.6 | 3.1 |
| Diazinon | 96.8 | 2.2 | Metamitron | 95.1 | 2.3 | Triclocarban | 106.0 | 3.0 |
| Dichlorvos | 93.8 | 2.1 | Methamidophos | 65.4 | 6.3 | Trifloxystrobin | 94.8 | 1.2 |
| Dicloran | 96.0 | 2.5 | Methoxyfenozide | 111.0 | 5.3 | Triflumuron | 87.6 | 2.2 |
| Diethofencarb | 92.2 | 1.9 | Metobromuron | 90.4 | 2.9 | XMC | 74.5 | 2.3 |
| Difenoconazole | 90.8 | 2.6 | Metolachlor | 98.3 | 4.3 | 0.0 | 0.0 |
In this way, the reproducibility of the method known as QuEChERS is improved, and we shall now call it A-QuERChERS (Agytax - Quick Easy Reproducible Cheap Rugged and Safe), significantly increasing the effectiveness (% recovery) of the extraction process.