Dispersive-Solid Phase Extraction(D-SPE) Development of Multiple Pesticides Residue Analysis Method in Agricultural Product using Dispersive-Solid Phase Extraction(D-SPE),,,,,,, Han-Taek Kim, Yong-Bae Park, Sun-Il Hwang, Hong-Rae Jung, Yun-Sung Kim, Mi-Hui Son, Wook-Hyun Cho, Kyeng-Suk Chae Anyang Agricultural Products Inspection Team Abstract : Method using Dispersive-Solid Phase Extraciton(D-SPE) was carried out to method development for multiple pesticides residue analysis in agricultural products through application of fast clean-up method and GC-TOF/MS(Time-of-Flight/mass spectrometer) to achieve qualitative and quantitative analysis. To multiple pesticide residue analysis GC/ECD, GC/NPD, and a variety of detection devices are a lot of time and a time consuming job. To complement for the GC and mass spectrometer (MS) and which uses a combination. Particularly, without losing qualitative information to increase selectivity and sensitivity GC-TOF/MS analysis of the pesticide is effective. Widely used clean-up method took about 2 hour of extraction, concentration and purification. Recently, Product using Dispersive-Solid Phase Extraction(D-SPE) should which take about 30 minutes per 1 sample of extraction and purification. Multi-residue analysis of pesticide has been developed with the D-SPE method by concurrent use of GC-TOF/MS. In order to ensure the reliability of the method. The D-SPE for multi-residue analysis method was used to achieve fast extraction and SPE and dispersive clean-up method of pesticide residue analysis. Multi-residue analysis of many pesticides were devised combining with the D-SPE method and followed by GC-TOF/MS residue analysis. To minimize matrix effects, matrix-matched standards were used for calibration curves of the concentration levels of the correlation coefficient was 5-9 points ( 0.01 5.0 mg/kg) standard solution (R 2 >0.999). Average recovery rates ranged from 80 to 130% of all pesticides at fortification levels of nine concentrations (0.01 5.0 mg/kg). The results showed that the QuEChERS sample preparation and GC-TOF/MS analysis can be applied to multi-residue analysis of pesticides in agricultural products. Key words : D-SPE(Dispersive-Solid Phase Extraction), QuEChERS, Pesticides, Multiple Pesticides Residue Analysis Method : GC-TOF/MS. GC/ECD, GC/NPD. GC (Mass Spectrometer)., GC-TOF/MS.,, 1 2. D-SPE, 1 20~30. D-SPE GC-TOF/MS. D-SPE GC-TOF/MS 80 130%, LOD 0.016 ~ 0.114 mg/kg, LOQ 0.047 ~ 0.436 mg/kg. 5 ~ 9 (0.01 5.0 mg/kg) 0.999. : D-SPE,,
1.,,,,. 1),. EPA, (MRLs : Maximum Residue Limits) 2), 4..,.. 1 (Multiresidue analytical method) (Individual analytical method). 1960 FDA Mill 3), California Department of Food & Agriculture(CDFA) 4), GC(Gas Chromatography), LC(Liquid Chromatography).,. 5,6),,. (Agricultural Research Service, ARS) QuEChERS 7) (Quick, easy, cheap, effective, rugged, safe). GC/NPD, GC/ECD LC/UVD, LC/FLD, GC/MS(Gas Chromatography Mass Spectrometry), LC/MS (Liquid Chromatography Mass Spectrometry), GC/MS/MS(Gas Chromatography Mass / Mass Spectrometry), LC/MS/MS(Liquid Chromatography Mass / Mass spectrometry), GC-TOF/MS(Gas Chromatography Time Of Flight Mass Spectrometry), LC-TOF/MS(Liquid Chromatography Time of Flight Mass Spectrometry). 8-22) QuEChERS D- SPE GC-TOF/MS,.
2. 2.1. Aectonitrile, Hexane, Aectone (Wako, Japan), Dr. Ehrenstorfer(Germany). Magnesium sulfate, Sodium Acetate, Sodium Chloride, Primary Secondary Amine(PSA) Ceramic homogenizer Agilent Technologies (USA). TurboVab LV(Caliper LS, USA). 2.3. 30 D-SPE. (Lattuce), (Spinach), (Korean cabbage). 2.4. 2.2. 2.4.1. Extraction GC/ECD, GC/NPD (Agilent Technologies, 7890A, USA) GC-TOF/MS(GC: Agilent, USA, TOF/MSD: Leco, pegasus HT, Singapore), Table 1. 2.. Extraction Clean-up Combi-514R(Hanil Science Industrial, Korea) 500g 10g 4.0g ± 0.2g MgSO 4, 1.0g ± 0.05g trisodium citrate dihydrate, 1.0g ± NaCl 50ml (Extraction kit), MeCN(Aectonitrile) 10mL. 1 (3,000 rpm) 5. Table 1. Analytical conditions of GC-TOF/MS Parameter condition Instrument Agilent 7890 Injector Agilent 7683B Detector TOF Column Rtx-5MS(30m 0.25mm,0.25μm) Injection volume 1μL Injection mode Splitless Carrier gas He Flow rate 1.75 ml/min Injector temp. 250 Transfer line temp. 260 Ionization mode EI Ion source temp. 220 Start mass(u) 50 End mass(u) 550 Acqsition(spectra/sec.) 20 spectra/sec Detector viltage 1900V Electron energy(volts) -70 Oven temp. 70 (3min) 20 /min 180 (0min) 5 /min 300 (7.5min)
Table 2. Analytical conditions of GC/ECD and GC/NPD Instruments Agilent 7890 Detector type ECD NPD Injection mode & vol. Injector temp. split(5:1), 1μl 270 splitless, 1μl 300 Column front DB-1701(30 m 0.25 mm, 0.25 μm ) DB-35(30 m 0.25 mm, 0.25 μm ) back DB-5(30 m 0.25 mm, 0.25 μm ) DB-5(30 m 0.25 mm, 0.25μm ) Gas N 2 (1 ml/min) He(1 ml/min) Oven temp. 130 (1min) 8 /min 180 (1min) 160 (1min) 4.7 /min 240 (4min 4 /min 210 (3min) 10 /min )13 (min) 275 (17min) 295 (5min) Detector temp. 300 320 2.4.2. Clean-up 3. 6mL 900mg anhydorous MgSO 4, 125mg Primary Secondary Amine(PSA) 15mL, PSA 1. 5 (3,000rpm) 3mL, 600uL(20% Acetone/Hexane). 2.4.3. 5 mg/kg. (Limit of detection, LOD) (Limit of quantification) 9 ICH(International Conference on Harmonisation of Technical Requirements for Registration of Phamaceuticals for Human Use). LOD=3.3δ/S LOQ=10δ/S δ = The standard deviation of the response S = The slope of the calibration curve 3.1. 23) MeCN. D-SPE. 8.8%, 2.6%. 24), ph. citrate buffer acetate buffer ph. 25,26) extraction citrate buffer.. D-SPE Primary secondary amine(psa) Clean-up. D-SPE A-1, B-1, C-1
A-2, B-2, C-2 GC/ECD GC/NPD Chromatogram Fig. 1.. Chlorpyrifos D-SPE A-1(0.36 mg/kg), B-1(0.26 mg/kg) A-2(0.22 mg/kg), B-2(0.13 mg/kg) baseline. C-1 C-2 D-SPE Propamocrab 1.96 mg/kg. Propamocarb D-SPE. 3.2. GC-TOF/MS 122 Retention time, Quant. mass, R 2, Table 3.. R 2 0.999 LOD는 0.016 ~ 0.114 mg/kg, LOQ는 0.047 ~ 0.436 mg/kg 으로나타났다. (Lattuce), (Spinach), (Chinese cabbage) Piperophos 147.4%, Difenconazole 148.5% 이외의성분들의회수율은상추 80 ~ 128.3%, 시금치 79.8 ~ 129.8%, 얼갈이 80.8 ~ 129.8% 로양호하였다. Fig. 1. Comparison of chromatogram between D-SPE Method and multiple pesticide residue analysis method by GC/ECD and GC/NPD (A-1, B-1, C-1 : Conducted D-SPE method, A-2, B-2, C-2 : Conducted multiple pesticide residue analysis method)
Table 3. Retention time(r.t.), Quant. Mass, Determination Coefficient(R 2 ), LOD, LOQ and Recovery obtained by D-SPE method preparation and GC-TOF/MS analysis Name R.T. Quant Recovery LOD LOQ R 2 Korean mass lettuce spinach Cabbage Acrinathrin 16:08.5 181 0.080 0.242 0.99985 81.5 99.8 129.4 Alachlor 10:15.9 160 0.044 0.134 0.99995 85.9 113.0 127.4 Aldrin 10:54.9 263 0.027 0.083 0.99997 121.0 94.9 117.8 Alpha-BHC 08:26.7 181 0.054 0.163 0.99987 102.8 83.3 83.8 Alpha-endosulfan 12:18.2 64 0.017 0.051 0.99999 89.5 94.4 103.2 Anilofos 15:23.9 125 0.017 0.052 0.99999 105.7 115.8 119.4 Beta-Endosulfan 13:21.8 64 0.021 0.063 0.99999 103.2 101.3 90.8 Bifenthrin 15:02.4 181 0.084 0.253 0.99968 122.0 111.8 198.2 Bitrertanol 16:41.7 170 0.038 0.115 0.99996 90.2 119.0 108.4 Bromacil 10:45.2 205 0.051 0.153 0.99994 126.4 111.5 106.6 Bromopropylate 15:00.7 185 0.047 0.143 0.99995 121.9 121.6 97.6 Cadusafos 08:14.5 159 0.095 0.287 0.99978 118.7 109.7 121.8 Captan 11:49.0 79 0.076 0.231 0.99995 84.3 110.2 90.3 Carbophenothion 13:54.9 157 0.05 0.153 0.99987 123.5 123.8 100.0 Chlorofenapyr 13:10.7 59 0.043 0.129 0.99996 88.6 117.4 113.6 Chlorobenzilate 13:17.4 139 0.077 0.232 0.99973 134.5 117.1 115.8 Chlorothalonil 09:31.0 266 0.049 0.148 0.99994 81.9 95.2 86.5 Chlorpyrifos(phos) 11:00.0 97 0.074 0.225 0.99975 113.7 119.0 125.1 Chloropyrifos-Methyl 10:08.1 125 0.095 0.287 0.99978 109.8 123.1 116.7 Cyflufenamid 13:06.9 91 0.043 0.13 0.99992 116.5 104.4 123.0 Cyhalothrin 16:00.2 197 0.085 0.258 0.99982 89.5 82.9 123.7 Cypermethrin 17:48.1 181 0.049 0.149 0.99998 119.7 104.6 130.6 Cyproconazole 13:08.2 222 0.033 0.1 0.99997 85.7 126.2 105.0 Cyprodinil 11:29.0 224 0.031 0.094 0.99998 96.7 117.1 117.5 Diazinon 09:14.2 137 0.057 0.174 0.99985 123.4 116.7 122.0 Dichlorfluanid 10:48.2 123 0.065 0.198 0.99981 81.4 95.9 90.5 Dicofol 11:04.1 111 0.059 0.178 0.99992 120.0 117.5 101.4 Dieldrin 12:47.4 79 0.073 0.221 0.99976 105.0 105.9 115.8 Diethofencarb 10:51.8 124 0.095 0.287 0.99978 86.0 129.7 116.4 Difenconazole 12:07.1 265 0.039 0.119 0.99996 111.1 129.7 148.5 Dimepiperate 11:49.3 119 0.071 0.216 0.99977 84.3 103.0 117.5 Diniconazole 13:24.0 70 0.086 0.261 0.99993 116.2 121.2 87.6 Diphenamid 11:22.5 72 0.096 0.29 0.99958 86.1 115.3 106.6 Diphenylamine 07:44.8 169 0.016 0.049 0.99999 103.2 120.3 128.2 Dithiopyr 10:31.6 306 0.065 0.196 0.9999 91.2 111.8 109.4 Endosulfan-sulfate 14:07.5 272 0.091 0.277 0.9998 116.0 123.7 123.3 Endrin 13:11.2 81 0.119 0.36 0.99966 128.6 106.5 116.8 EPN 15:04.0 157 0.052 0.159 0.99988 128.4 115.7 85.6 Esprocarb 10:40.0 91 0.047 0.141 0.99984 109.1 92.8 101.8 Ethion 13:31.9 231 0.023 0.068 0.99998 98.1 104.8 89.5
Table 3. Continue. Name R.T. Quant mass Recovery LOD LOQ R 2 lettuce spinach Korean Cabbage Etrimfos 09:31.0 153 0.047 0.142 0.99989 126.8 122.8 84.9 Fenamidone 15:19.5 238 0.059 0.179 0.99991 104.7 80.1 129.8 Fenarimol 16:12.0 139 0.018 0.056 0.99998 107.6 129.8 122.6 Fenazaquin 15:17.8 145 0.029 0.088 0.99998 112.8 113.0 95.7 Fenobucarb 07:36.5 121 0.012 0.035 0.99996 118.5 124.1 81.6 Fenothiocarb 12:09.5 72 0.037 0.113 0.99993 122.6 97.6 117.2 Fenoxanil 13:12.1 189 0.065 0.196 0.99978 90.8 121.9 126.4 Fenpropathrin 15:10.2 181 0.073 0.221 0.99987 117.0 105.4 104.6 Fenthion 10:58.9 278 0.067 0.203 0.99977 84.6 112.4 129.3 Fenvalerate 18:43.6 125 0.055 0.167 0.99997 114.2 117.1 101.0 Fipronil 11:46.2 367 0.144 0.436 0.9995 88.3 123.9 105.4 Fludioxonil 12:49.3 248 0.072 0.218 0.99987 110.3 112.9 97.8 Flusilazole 12:53.9 233 0.05 0.152 0.99987 112.3 105.3 127.4 Flutolanil 12:31.6 173 0.04 0.122 0.99993 106.9 114.9 122.3 Folpet 11:56.3 79 0.045 0.136 0.99998 102.6 106.8 111.2 Fthalide 11:20.9 243 0.021 0.065 0.99999 116.2 107.6 80.8 GAMMA-BHC 09:01.0 181 0.066 0.199 0.9998 114.7 87.9 81.9 Heptachlor-exo-epoxide 11:38.9 81 0.034 0.102 0.99995 126.2 70.2 87.6 Hexaconazole 12:30.5 83 0.04 0.122 0.99993 106.1 122.7 134.9 Imazalil 12:35.6 173 0.058 0.177 0.99997 82.3 127.4 112.5 Indanofan 15:20.8 139 0.018 0.055 0.99999 84.0 127.9 125.8 Indoxacarb 19:22.7 59 0.071 0.214 0.99995 120.3 116.2 122.8 Iprobenfos 09:37.8 204 0.118 0.359 0.99966 114.4 128.1 107.9 Iprodione 15:12.0 314 0.026 0.079 0.99984 90.5 89.0 118.9 Isazofos(phos) 09:29.0 97 0.031 0.093 0.99975 129.9 106.9 124.7 Isoprothiolane 12:37.6 118 0.04 0.122 0.99993 117.7 125.3 93.5 Kresoxim-Methyl 12:59.8 116 0.045 0.136 0.99991 100.4 107.9 126.3 Malathion 10:48.1 100 0.034 0.103 0.99994 87.4 119.7 85.7 Mecarbam 11:46.0 97 0.053 0.162 0.99985 110.2 120.7 123.4 Mepronil 13:41.7 119 0.022 0.067 0.99999 106.6 103.6 82.9 Metalaxyl 10:21.9 206 0.058 0.174 0.99992 87.4 125.6 115.7 Methidathion 12:07.0 145 0.094 0.285 0.99978 118.5 127.1 121.5 Methoxychlor 15:10.8 227 0.018 0.055 0.99999 105.3 90.8 123.2 Metrafenone 16:30.0 379 0.071 0.216 0.99988 120.8 109.9 112.2 Metribuzin 10:02.0 198 0.05 0.151 0.99994 87.1 91.4 104.6 Molinate 07:04.0 126 0.012 0.035 0.99996 125.3 125.1 116.7 Myclobutanil 12:51.3 179 0.084 0.254 0.99983 91.8 125.6 98.2 Nuarimol 14:25.5 107 0.058 0.176 0.99992 118.5 110.2 125.7 Oxadiazone 12:44.9 175 0.043 0.13 0.99992 131.6 117.8 115.1 Oxadixyl 13:36.8 132 0.063 0.191 0.99996 103.0 121.2 106.2 Parathion 11:01.3 109 0.073 0.221 0.99987 86.7 113.2 125.6
Table 3. Continue. Quant Recovery Name R.T. LOD LOQ R 2 Korean mass lettuce spinach Cabbage Parathion-Methyl 10:08.6 109 0.074 0.225 0.99971 104.6 84.0 114.9 Penconazole 11:37.5 159 0.075 0.228 0.99995 116.4 110.9 98.4 Pendimethalin 11:35.4 252 0.038 0.117 0.99993 114.9 101.3 100.9 Permethrin 16:46.7 183 0.028 0.084 0.99999 116.9 122.4 120.8 Phenthoate(PAP) 11:50.5 274 0.022 0.067 0.99999 118.2 110.5 117.2 Phorate 08:19.5 75 0.046 0.138 0.99985 85.2 129.9 120.2 Phosalone 15:41.0 182 0.019 0.056 0.99999 115.7 89.5 103.8 Piperophos 15:06.9 122 0.044 0.133 0.99995 116.7 147.7 120.2 Pirimicarb 09:44.3 166 0.033 0.101 0.99992 103.7 102.8 94.7 Pirimiphos-Ethyl 11:22.3 168 0.018 0.054 0.99998 123.6 115.3 116.8 Pirimiphos-Methyl 10:38.6 125 0.068 0.205 0.99989 125.3 115.2 122.9 Probendazole 09:01.5 130 0.077 0.235 0.99985 118.8 111.9 80.8 Prochloraz 12:05.0 70 0.083 0.252 0.99994 118.2 125.8 112.4 Procymidone 11:55.8 96 0.058 0.176 0.99985 80.8 100.7 124.5 Profenofos 12:40.7 139 0.046 0.138 0.99991 115.5 99.4 112.3 Propamocarb 06:03.2 58 0.029 0.088 0.99998 91.6 116.2 123.4 Propisochlor 10:18.3 162 0.032 0.097 0.99986 80.0 94.1 127.9 Prothiophos 12:34.1 113 0.06 0.183 0.99991 80.7 91.8 80.0 Pyrazophos 16:15.5 221 0.022 0.067 0.99999 115.6 84.9 100.9 Pyridalyl 18:07.4 204 0.083 0.251 0.99994 100.6 108.7 125.2 Pyrimidifen 18:32.6 184 0.071 0.214 0.99995 122.3 90.5 85.4 Pyriminobac-methyl 14:16.3 302 0.096 0.291 0.99952 129.4 119.1 109.5 Quinalphos 11:48.7 146 0.043 0.131 0.9999 103.2 86.6 131.9 Simazine 08:44.0 201 0.044 0.132 0.9995 116.5 124.4 110.9 Simeconazole 10:09.5 121 0.049 0.147 0.99967 113.5 109.4 115.7 Tebuconazole 14:21.6 125 0.024 0.072 0.99997 92.9 123.9 100.9 Tefluthrin 09:22.7 264 0.032 0.097 0.99993 97.4 120.1 123.5 Terbufos 09:02.1 231 0.055 0.167 0.99978 105.2 116.4 129.7 Terbuthylazine 09:03.5 177 0.077 0.233 0.99986 80.2 103.7 127.6 Tetraconazole 11:08.9 336 0.028 0.084 0.99998 117.6 94.7 98.7 Tetradifon 15:32.2 111 0.075 0.226 0.99986 127.5 111.9 123.0 Thiazopyr 10:56.9 60 0.035 0.106 0.99991 120.7 102.4 107.5 Thifluzamide 12:56.4 166 0.043 0.130 0.99992 96.7 118.1 126.6 Thiometon 08:31.1 88 0.044 0.132 0.9995 128.3 124.3 114.5 Tolclofos-Methyl 10:13.6 265 0.073 0.222 0.99975 86.8 110.6 131.0 Triadimefon 11:03.4 57 0.021 0.064 0.99999 112.8 105.1 102.5 Triazophos 13:48.8 162 0.022 0.067 0.99999 97.7 113.6 119.4 Triflumizole 11:57.1 278 0.086 0.26 0.99982 118.9 127.8 119.9 Trifluralin 08:05.0 264 0.07 0.213 0.99978 82.0 106.3 100.4 Vinclozolin 10:06.0 198 0.016 0.047 0.99999 108.5 101.5 124.6 Zoxamide 11:51.7 187 0.097 0.293 0.99977 87.5 114.2 105.8
Fig. 2. Comparison of chromatogram between D-SPE method and multiple pesticides residue analysis method by GC-TOF/MS. (A-1, B-1, C-1 : Conducted by D-SPE method, A-2, B-2, C-2 : Conducted by multiple pesticide residue analysis method) 3.3 GC-TOF/MS 3.1. GC-TOF/MS Fig. 2.. Chlorpyrifos D-SPE a-1(0.38 mg/kg), b-1(0.23 mg/kg) a-2(0.24 mg/kg), b-2(0.15 mg/kg). Propamocarb D-SPE c-1 c-2. GC-TOF/MS GC/ECD, GC/NPD MS/MS MRM mode Full mass spectrum MS/MS matrix. library ion Ion-ratio MS/MS Mass. 28) D-SPE. c-1 Propamocarb. D-SPE. Mastovska K (2010). 27), matrix GC/ECD, GC/NPD GC-TOF/MS. GC
D-SPE,. 1. GC-TOF/MS LOD, LOQ R 2 R 2 0.999, LOD 0.016 ~ 0.114 mg/kg, LOQ 0.047 ~ 0.436 mg/kg., Piperophos 147.4%, Difenconazole 148.5%, 80 ~ 128.3%, 79.8 ~ 129.8%, 80.8 ~ 129.8%. 2. 경매전농산물 30건을대상으로 D-SPE방법과다종농약다성분방법으로전처리하여 GC/ECD와 GC/NPD로검사하였다. Chlorpyrifos 를 D-SPE 방법전처리한결과가다종농약다성분시험법으로전처리한결과보다검출농도가높게나타났으며, 다종농약다성분분석법으로는전처리되지않는 Propamocarb가 D-SPE 전처리시 1.96 mg/kg 농도로검출되었다. 3. 같은시료를 GC-TOF/MS로분석해본결과 D-SPE 방법으로전처리한 a-1, b-1 a-2, b-2, c-1 Propamocarb. D-SPE, Mass. GC-TOF/MS D-SPE. 4. D-SPE Propamocarb,. 5. 1. Eunhye Kim, Hyeri Lee, Hoon Choi, Joonkwan Moon, Soonsung Hong, Mihye Jeong, Kyunghun Park, Hyomin Kee, An Xue Hua, Jeonghan Kim, (2011), Method validation for monitoring of agricultural worker Exposure to insecticide fenthion, The Korean Journal of Pesticide Science, 15, 357~365. 2., (2012), - 2-3. Mills, P.A. Onley, J.H. Guither, R.A. 1963, Rapid method for chlorinated. pesticide residues in nonfatty foods. J. Assoc. Off. Anal. Chem.. 46, 186-191. 4. Lee, S. M., M. L. Papathakis, H. C. Feng, G. H. Hunter, J. E. Carr, (1991), Multipesticide residue method for fruits and vegetables, California Department of Food and Agriculture, Fresenius Journal of Analytical Chemistry, 339, 376-383. 5.. (2008).,,. 6. Park, M, H. Establishment of Multiple Pesticide Residue Analysis Method in Agricultural Products Using GC-MSD, (2012). Dept. of Environmental Engineering and Biotechnology. Graduate School of Convergence Science and Technology. Gyeongsang National University. Korea. 7. Anastassiades, M., Lehotay, S. J., Stajnbaher, D., Schenck,, F. J. (2003) Fast and easy multiresidue method empolying acetonitrile extraction/partitioning and "dispersive solid-phase extraction" for the determination pf pesticide residues in produce. Journal of AOAC
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