Sensitive Detection of Organophosphorus Pesticides in Medicinal ...
Supporting Information to:
Sensitive Detection of Organophosphorus Pesticides in Medicinal Plants
Using
Ultrasound-Assisted
Dispersive
Liquid−Liquid
Microextraction Combined with Sweeping Micellar Electrokinetic Chromatography Jin-Chao Wei, Ji Hu, Ji-Liang Cao, Jian-Bo Wan, Cheng-Wei He, Yuan-Jia Hu, Hao Hu, and Peng Li *
State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macau 999078, China
Table S1. Effects of dispersive solvent type on the extraction recoveries (%) of the investigated pesticides in UA-DLLME a.
Solvent
Extraction recoveries of pesticide (%) 4 5 6
1
2
3
7
8
9
MeCN
63.8±13.1
47.5±6.4
50.2±5.5
46.5±3.0
46.0±4.4
53.2±4.4
71.2±3.4
68.0±3.4
62.4±4.9
Acetone
63.7±4.8
65.9±1.3
66.5±5.6
61.1±3.9
62.4±8.0
60.1±7.3
65.5±7.6
63.6±11.3
57.7±4.2
MeOH
15.3±1.0
7.1±2.1
6.6±2.3
12.2±1.0
14.5±3.1
19.4±3.5
13.6±1.8
29.5±8.1
42.7±2.0
EtOH
41.3±6.1
31.3±1.1
32.9±2.4
34.2±1.3
32.6±1.9
42.5±1.0
46.2±1.4
49.5±3.5
42.1±2.0
a) Data are presented as Mean ± S.D. from three independent experiments. Other conditions: dispersive solvent, 1.0 mL; extraction solvent, 200 μl of chloroform; and aqueous solution, 5 mL of 4% NaCl solution. Pesticide assignment: 1. chlorfenvinphos, 2. parathion, 3. quinalphos, 4. fenitrothion, 5. azinphos-ethyl, 6. parathion-methyl, 7. fensulfothion, 8. methidathion, and 9. paraoxon.
Table S2. Effects of extraction solvent volume on the extraction recoveries (%) of the investigated pesticides in UA-DLLME a.
Volume (μL)
Extraction recoveries of pesticide (%) 4 5 6
1
2
3
7
8
9
150
66.2±7.3
68.6±6.1
70.6±4.6
70.3±1.4
68.5±1.7
68.9±2.8
68.3±1.1
63.0±0.4
66.4±1.8
200
100.0±13.7
85.5±8.3
90.3±4.3
87.2±13.7
88.5±9.9
83.3±10.6
79.9±3.7
81.2±8.1
73.7±8.8
250
81.3±1.9
75.7±26.5
72.3±20.3
74.2±20.1
74.8±19.8
74.7±11.9
77.3±5.3
75.3±4.1
71.9±11.0
300
98.6±18.3
89.8±11.2
89.8±1.0
87.0±8.6
90.3±7.2
86.0±7.5
82.3±2.4
77.6±3.6
77.8±6.9
350
98.2±10.7
85.9±15.9
88.3±10.2
93.7±10.9
93.6±16.0
93.3±10.7
85.3±3.8
82.2±2.4
80.9±8.3
400
92.4±7.0
88.6±17.7
86.0±8.6
89.6±10.3
88.1±12.8
87.2±10.8
85.4±6.3
86.7±6.6
81.7±11.5
a) Data are presented as Mean ± S.D. from three independent experiments. Other conditions: dispersive solvent, 1.0 mL of acetone; extraction solvent, chloroform; and aqueous solution, 5 mL of 4% NaCl solution. Pesticide assignment: 1. chlorfenvinphos, 2. parathion, 3. quinalphos, 4. fenitrothion, 5. azinphos-ethyl, 6. parathion-methyl, 7. fensulfothion, 8. methidathion, and 9. paraoxon.
Table S3. Effects of amounts of PSA on the extraction recoveries of the investigated pesticides in the cleanup procedure a.
PSA (mg)
Extraction recoveries of pesticide (%) 4 5 6
1
2
3
7
8
9
100
94.9±3.7
74.7±6.1
76.9±9.4
85.5±7.4
93.0±14.1
85.1±10.0
90.5±10.1
100.1±14.1
95.8±14.6
200
103.7±4.6
104.6±7.4
108.4±6.0
99.9±6.9
116.3±9.9
103.0±6.9
100.8±7.4
107.8±8.6
104.0±9.5
400
104.2±9.4
88.7±4.7
88.6±5.1
105.0±13.0
106.6±9.3
93.1±4.4
93.7±7.8
108.1±9.9
104.2±11.6
800
102.6±4.4
90.7±11.3
98.0±9.7
93.5±2.8
108.2±4.4
90.3±6.0
85.9±6.2
99.5±4.9
92.2±5.1
a) Data are presented as Mean ± S.D. from three independent experiments. Pesticide assignment: 1. chlorfenvinphos, 2. parathion, 3. quinalphos, 4. fenitrothion, 5. azinphos-ethyl, 6. parathion-methyl, 7. fensulfothion, 8. methidathion, and 9. paraoxon.
Table S4. Effects of amounts of GCB on the extraction recoveries of the investigated pesticides in the cleanup procedure a.
GCB (mg)
Extraction recoveries of pesticide (%) 4 5 6
1
2
3
7
8
9
10
99.9±10.9
87.0±18.5
67.1±17.1
100.9±7.1
69.9±23.5
102.3±10.9
94.4±10.9
93.9±20.3
98.7±15.0
30
98.9±7.4
85.0±5.8
59.7±3.3
98.5±5.4
57.6±11.4
98.5±4.3
89.0±7.7
84.7±13.1
88.5±8.6
50
88.4±5.2
80.5±2.8
46.6±2.5
95.5±4.4
42.6±4.6
100.1±5.9
90.5±6.5
89.4±8.0
90.5±8.0
80
87.8±10.0
77.6±11.7
40.2±2.8
73.5±2.5
32.2±12.5
88.8±4.6
86.5±5.8
92.8±12.9
97.5±7.2
100
95.1±9.9
78.3±14.3
33.7±8.0
80.4±5.7
22.9±1.2
91.4±4.0
88.3±5.9
87.3±6.9
89.9±11.8
a) Data are presented as Mean ± S.D. from three independent experiments. Pesticide assignment: 1. chlorfenvinphos, 2. parathion, 3. quinalphos, 4. fenitrothion, 5. azinphos-ethyl, 6. parathion-methyl, 7. fensulfothion, 8. methidathion, and 9. paraoxon.
Table S5. The optimized conditions for the procedures of UA-DLLME and sample cleanup. Procedure
Conditions
Optimal values
UA-DLLME
Type and volume of extraction solvent
Acetone, 1.0 mL
Type and volume of dispersive solvent
Chloroform, 350 μL
Addition of salt
Sodium chloride, 300 mg
Ultrasound-assisted extraction time
1 min
Amount of GCB
30 mg
Amount of PSA
200 mg
Sample Cleanup
Table S6. Comparison of UA-DLLME−sweeping-MEKC with other analytical methods for determination of OPPs in real samples. LODa
Methods
Extraction time
Samples amount
(μg kg )
(min)
(g)
410-2250
—
2.5
-1
LLE−GC-FIDb
Analytes Dimethoate, chlorpyrifos, diazinon, fenitrothion, malathion, chlorfenvinphos, methidathion, fenthion and tetrachlorvinphos
Samples
Reference
Vegetable
[1]
Medicinal plant
[2]
Peanut oil
[3]
Methamidophos, trichlorfon, dichlorvos, acephate, formothion, omethoate, monocrotophos, phorate, demeton, dimethoate, diazinon, disulfoton, phosphamidon, parathion-methyl, GC-FPD
c
1-10
—
0.5
chlorpyrifos-methyl, fenitrothion, malathion, fenthion, parathion, chlorpyrifos, isocarbophos, isofenphos-methyl, quinalphos, methidathion, ditalimfos, profenofos, ethion, triazophos, phosmet, azinphos-methyl, and phosalone, Phorate, diazinon, tolclofosmethyl, fenitrothin, malathion,
QuEChERS−GC-MSd
0.7-1.6
22.5
5
UASE−DLLME−SPO−HPLC-UVe
1-4
35
1
Diazinon, fenthion, phosalone and chloropyrifose
Vegetable
[4]
MEKC-QD/LIFf
50-180
70
10
Mevinphos, methidathion, diazinon and phosalone.
Vegetable
[5]
MISPE−CEg
4.9
270
50
Trichlorfon
Vegetable
[6]
Medicinal plant
This work
fenthion, isocarbophos, quinalphos and phenamiphos
Chlorfenvinphos, parathion, quinalphos, fenitrothion, UA-DLLME−sweeping-MEKC
h
2-8
27
0.5
azinphos-ethyl, parathion-methyl, fensulfothion, methidathion and paraoxon.
a b
LOD, limit of detection. Liquid-liquid extraction−gas chromatography-flame ionization detector (large volume injection).
c
Gas chromatography with flame photometric detector. The ‘Quick, Easy, Cheap, Effective, Rugged and Safe’ method−gas chromatography-mass spectrometry. e Ultrasonic assisted solvent extraction−dispersive liquid−liquid microextraction−solidification of floating organic drop−high performance liquid chromatography-ultraviolet detector. d
f
Micellar electrokinetic chromatography with immobilized quantum dot-laser induce fluorescence detection.
g
Molecularly imprinted solid-phase extraction coupled to capillary electrophoresis. Ultrasound-assisted dispersive liquid−liquid microextraction combined with sweeping micellar electrokinetic chromatography.
h
Reference [1] Cortes, J. M.; Sanchez, R.; Diaz-Plaza, E. M.; Villen, J.; Vazquez, A. Large volume GC injection for the analysis of organophosphorus pesticides in vegetables using the through oven transfer adsorption desorption (TOTAD) interface. J. Agric. Food Chem. 2006, 54, 1997−2002. [2] Zhao, X.S.; Kong, W.J.; Wei, J.H.; Yang, M.H. Gas chromatography with flame photometric detection of 31 organophosphorus pesticide residues in Alpinia oxyphylla dried fruits, Food Chem. 2014, 162, 270-276. [3] Su, R.; Xu, X.; Wang, X.H.; Li, D.; Li, X.Y.; Zhang, H.Q., Yu, A.M. (2011). Determination of organophosphorus pesticides in peanut oil by dispersive solid phase extraction gas chromatography-mass spectrometry. J. Chromatogr. B. 2011, 879, 3423-3428. [4] Pirsaheb, M.; Fattahi, N.; Shamsipur, M. Determination of organophosphorous pesticides in summer crops using ultrasound-assisted solvent extraction followed by dispersive liquideliquid microextraction based on the solidification of floating organic drop. Food Control. 2013, 34, 378-385. [5] Chen, Q.D.; Fung Y.S. Capillary electrophoresis with immobilized quantum dot fluorescence detection for rapid determination of organophosphorus pesticides in vegetables. Electrophoresis 2010, 31, 3107-3114. [6] Zhao, T.; Gao, H.J.; Wang, X.L.; Zhang, L.M.; Qiao, X.G.; Xu, Z.X. Study on a Molecularly Imprinted Solid-Phase Extraction Coupled to Capillary Electrophoresis Method for the Determination of Trace Trichlorfon in Vegetables. Food Anal. Methods. 2014, 7, 1159-1165.
Figure S1 The electropherograms of the Lycium chinense sample spiked with analytes at 0.5 mg kg−1 (A) and the Lycium chinense sample (B). Pesticide assignment: 1. chlorfenvinphos, 2. parathion, 3. quinalphos, 4. fenitrothion, 5. azinphos-ethyl, 6. parathion-methyl, 7. fensulfothion, 8. methidathion, 9. paraoxon, and u. unknown.
Figure S2 The electropherograms of the Dioscorea opposite sample spiked with analytes at 0.5 mg kg−1 (A) and the Dioscorea opposite sample (B). Pesticide assignment: 1. chlorfenvinphos, 2. parathion, 3. quinalphos, 4. fenitrothion, 5. azinphos-ethyl, 6. parathion-methyl, 7. fensulfothion, 8. methidathion, 9. paraoxon, and u. unknown.
Sensitive Detection of Organophosphorus Pesticides in Medicinal Plants
Using
Ultrasound-Assisted
Dispersive
Liquid−Liquid
Microextraction Combined with Sweeping Micellar Electrokinetic Chromatography Jin-Chao Wei, Ji Hu, Ji-Liang Cao, Jian-Bo Wan, Cheng-Wei He, Yuan-Jia Hu, Hao Hu, and Peng Li *
State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macau 999078, China
Table S1. Effects of dispersive solvent type on the extraction recoveries (%) of the investigated pesticides in UA-DLLME a.
Solvent
Extraction recoveries of pesticide (%) 4 5 6
1
2
3
7
8
9
MeCN
63.8±13.1
47.5±6.4
50.2±5.5
46.5±3.0
46.0±4.4
53.2±4.4
71.2±3.4
68.0±3.4
62.4±4.9
Acetone
63.7±4.8
65.9±1.3
66.5±5.6
61.1±3.9
62.4±8.0
60.1±7.3
65.5±7.6
63.6±11.3
57.7±4.2
MeOH
15.3±1.0
7.1±2.1
6.6±2.3
12.2±1.0
14.5±3.1
19.4±3.5
13.6±1.8
29.5±8.1
42.7±2.0
EtOH
41.3±6.1
31.3±1.1
32.9±2.4
34.2±1.3
32.6±1.9
42.5±1.0
46.2±1.4
49.5±3.5
42.1±2.0
a) Data are presented as Mean ± S.D. from three independent experiments. Other conditions: dispersive solvent, 1.0 mL; extraction solvent, 200 μl of chloroform; and aqueous solution, 5 mL of 4% NaCl solution. Pesticide assignment: 1. chlorfenvinphos, 2. parathion, 3. quinalphos, 4. fenitrothion, 5. azinphos-ethyl, 6. parathion-methyl, 7. fensulfothion, 8. methidathion, and 9. paraoxon.
Table S2. Effects of extraction solvent volume on the extraction recoveries (%) of the investigated pesticides in UA-DLLME a.
Volume (μL)
Extraction recoveries of pesticide (%) 4 5 6
1
2
3
7
8
9
150
66.2±7.3
68.6±6.1
70.6±4.6
70.3±1.4
68.5±1.7
68.9±2.8
68.3±1.1
63.0±0.4
66.4±1.8
200
100.0±13.7
85.5±8.3
90.3±4.3
87.2±13.7
88.5±9.9
83.3±10.6
79.9±3.7
81.2±8.1
73.7±8.8
250
81.3±1.9
75.7±26.5
72.3±20.3
74.2±20.1
74.8±19.8
74.7±11.9
77.3±5.3
75.3±4.1
71.9±11.0
300
98.6±18.3
89.8±11.2
89.8±1.0
87.0±8.6
90.3±7.2
86.0±7.5
82.3±2.4
77.6±3.6
77.8±6.9
350
98.2±10.7
85.9±15.9
88.3±10.2
93.7±10.9
93.6±16.0
93.3±10.7
85.3±3.8
82.2±2.4
80.9±8.3
400
92.4±7.0
88.6±17.7
86.0±8.6
89.6±10.3
88.1±12.8
87.2±10.8
85.4±6.3
86.7±6.6
81.7±11.5
a) Data are presented as Mean ± S.D. from three independent experiments. Other conditions: dispersive solvent, 1.0 mL of acetone; extraction solvent, chloroform; and aqueous solution, 5 mL of 4% NaCl solution. Pesticide assignment: 1. chlorfenvinphos, 2. parathion, 3. quinalphos, 4. fenitrothion, 5. azinphos-ethyl, 6. parathion-methyl, 7. fensulfothion, 8. methidathion, and 9. paraoxon.
Table S3. Effects of amounts of PSA on the extraction recoveries of the investigated pesticides in the cleanup procedure a.
PSA (mg)
Extraction recoveries of pesticide (%) 4 5 6
1
2
3
7
8
9
100
94.9±3.7
74.7±6.1
76.9±9.4
85.5±7.4
93.0±14.1
85.1±10.0
90.5±10.1
100.1±14.1
95.8±14.6
200
103.7±4.6
104.6±7.4
108.4±6.0
99.9±6.9
116.3±9.9
103.0±6.9
100.8±7.4
107.8±8.6
104.0±9.5
400
104.2±9.4
88.7±4.7
88.6±5.1
105.0±13.0
106.6±9.3
93.1±4.4
93.7±7.8
108.1±9.9
104.2±11.6
800
102.6±4.4
90.7±11.3
98.0±9.7
93.5±2.8
108.2±4.4
90.3±6.0
85.9±6.2
99.5±4.9
92.2±5.1
a) Data are presented as Mean ± S.D. from three independent experiments. Pesticide assignment: 1. chlorfenvinphos, 2. parathion, 3. quinalphos, 4. fenitrothion, 5. azinphos-ethyl, 6. parathion-methyl, 7. fensulfothion, 8. methidathion, and 9. paraoxon.
Table S4. Effects of amounts of GCB on the extraction recoveries of the investigated pesticides in the cleanup procedure a.
GCB (mg)
Extraction recoveries of pesticide (%) 4 5 6
1
2
3
7
8
9
10
99.9±10.9
87.0±18.5
67.1±17.1
100.9±7.1
69.9±23.5
102.3±10.9
94.4±10.9
93.9±20.3
98.7±15.0
30
98.9±7.4
85.0±5.8
59.7±3.3
98.5±5.4
57.6±11.4
98.5±4.3
89.0±7.7
84.7±13.1
88.5±8.6
50
88.4±5.2
80.5±2.8
46.6±2.5
95.5±4.4
42.6±4.6
100.1±5.9
90.5±6.5
89.4±8.0
90.5±8.0
80
87.8±10.0
77.6±11.7
40.2±2.8
73.5±2.5
32.2±12.5
88.8±4.6
86.5±5.8
92.8±12.9
97.5±7.2
100
95.1±9.9
78.3±14.3
33.7±8.0
80.4±5.7
22.9±1.2
91.4±4.0
88.3±5.9
87.3±6.9
89.9±11.8
a) Data are presented as Mean ± S.D. from three independent experiments. Pesticide assignment: 1. chlorfenvinphos, 2. parathion, 3. quinalphos, 4. fenitrothion, 5. azinphos-ethyl, 6. parathion-methyl, 7. fensulfothion, 8. methidathion, and 9. paraoxon.
Table S5. The optimized conditions for the procedures of UA-DLLME and sample cleanup. Procedure
Conditions
Optimal values
UA-DLLME
Type and volume of extraction solvent
Acetone, 1.0 mL
Type and volume of dispersive solvent
Chloroform, 350 μL
Addition of salt
Sodium chloride, 300 mg
Ultrasound-assisted extraction time
1 min
Amount of GCB
30 mg
Amount of PSA
200 mg
Sample Cleanup
Table S6. Comparison of UA-DLLME−sweeping-MEKC with other analytical methods for determination of OPPs in real samples. LODa
Methods
Extraction time
Samples amount
(μg kg )
(min)
(g)
410-2250
—
2.5
-1
LLE−GC-FIDb
Analytes Dimethoate, chlorpyrifos, diazinon, fenitrothion, malathion, chlorfenvinphos, methidathion, fenthion and tetrachlorvinphos
Samples
Reference
Vegetable
[1]
Medicinal plant
[2]
Peanut oil
[3]
Methamidophos, trichlorfon, dichlorvos, acephate, formothion, omethoate, monocrotophos, phorate, demeton, dimethoate, diazinon, disulfoton, phosphamidon, parathion-methyl, GC-FPD
c
1-10
—
0.5
chlorpyrifos-methyl, fenitrothion, malathion, fenthion, parathion, chlorpyrifos, isocarbophos, isofenphos-methyl, quinalphos, methidathion, ditalimfos, profenofos, ethion, triazophos, phosmet, azinphos-methyl, and phosalone, Phorate, diazinon, tolclofosmethyl, fenitrothin, malathion,
QuEChERS−GC-MSd
0.7-1.6
22.5
5
UASE−DLLME−SPO−HPLC-UVe
1-4
35
1
Diazinon, fenthion, phosalone and chloropyrifose
Vegetable
[4]
MEKC-QD/LIFf
50-180
70
10
Mevinphos, methidathion, diazinon and phosalone.
Vegetable
[5]
MISPE−CEg
4.9
270
50
Trichlorfon
Vegetable
[6]
Medicinal plant
This work
fenthion, isocarbophos, quinalphos and phenamiphos
Chlorfenvinphos, parathion, quinalphos, fenitrothion, UA-DLLME−sweeping-MEKC
h
2-8
27
0.5
azinphos-ethyl, parathion-methyl, fensulfothion, methidathion and paraoxon.
a b
LOD, limit of detection. Liquid-liquid extraction−gas chromatography-flame ionization detector (large volume injection).
c
Gas chromatography with flame photometric detector. The ‘Quick, Easy, Cheap, Effective, Rugged and Safe’ method−gas chromatography-mass spectrometry. e Ultrasonic assisted solvent extraction−dispersive liquid−liquid microextraction−solidification of floating organic drop−high performance liquid chromatography-ultraviolet detector. d
f
Micellar electrokinetic chromatography with immobilized quantum dot-laser induce fluorescence detection.
g
Molecularly imprinted solid-phase extraction coupled to capillary electrophoresis. Ultrasound-assisted dispersive liquid−liquid microextraction combined with sweeping micellar electrokinetic chromatography.
h
Reference [1] Cortes, J. M.; Sanchez, R.; Diaz-Plaza, E. M.; Villen, J.; Vazquez, A. Large volume GC injection for the analysis of organophosphorus pesticides in vegetables using the through oven transfer adsorption desorption (TOTAD) interface. J. Agric. Food Chem. 2006, 54, 1997−2002. [2] Zhao, X.S.; Kong, W.J.; Wei, J.H.; Yang, M.H. Gas chromatography with flame photometric detection of 31 organophosphorus pesticide residues in Alpinia oxyphylla dried fruits, Food Chem. 2014, 162, 270-276. [3] Su, R.; Xu, X.; Wang, X.H.; Li, D.; Li, X.Y.; Zhang, H.Q., Yu, A.M. (2011). Determination of organophosphorus pesticides in peanut oil by dispersive solid phase extraction gas chromatography-mass spectrometry. J. Chromatogr. B. 2011, 879, 3423-3428. [4] Pirsaheb, M.; Fattahi, N.; Shamsipur, M. Determination of organophosphorous pesticides in summer crops using ultrasound-assisted solvent extraction followed by dispersive liquideliquid microextraction based on the solidification of floating organic drop. Food Control. 2013, 34, 378-385. [5] Chen, Q.D.; Fung Y.S. Capillary electrophoresis with immobilized quantum dot fluorescence detection for rapid determination of organophosphorus pesticides in vegetables. Electrophoresis 2010, 31, 3107-3114. [6] Zhao, T.; Gao, H.J.; Wang, X.L.; Zhang, L.M.; Qiao, X.G.; Xu, Z.X. Study on a Molecularly Imprinted Solid-Phase Extraction Coupled to Capillary Electrophoresis Method for the Determination of Trace Trichlorfon in Vegetables. Food Anal. Methods. 2014, 7, 1159-1165.
Figure S1 The electropherograms of the Lycium chinense sample spiked with analytes at 0.5 mg kg−1 (A) and the Lycium chinense sample (B). Pesticide assignment: 1. chlorfenvinphos, 2. parathion, 3. quinalphos, 4. fenitrothion, 5. azinphos-ethyl, 6. parathion-methyl, 7. fensulfothion, 8. methidathion, 9. paraoxon, and u. unknown.
Figure S2 The electropherograms of the Dioscorea opposite sample spiked with analytes at 0.5 mg kg−1 (A) and the Dioscorea opposite sample (B). Pesticide assignment: 1. chlorfenvinphos, 2. parathion, 3. quinalphos, 4. fenitrothion, 5. azinphos-ethyl, 6. parathion-methyl, 7. fensulfothion, 8. methidathion, 9. paraoxon, and u. unknown.
