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Sepaths Application book
pag. 2
CONTENT
Carbaryl in Tap Water by Sepaths-6 SPE/HPLC……………………………………………...pag.3
Organochlorine Pesticides Residue in Tap Water by Sepaths-6 SPE/GC-ECD………………pag.8
SPE for Nitrosamines in Water...........................................................................................…...pag.14
SPE for EPA 608 for Organochlorine Pesticides and PCB’s………………………………….pag.15
SPE for EPA 625 for Semivolatile Organics in Wastewaters…………………………………pag.16
Method for Total Petroleum Hydrocarbon in Water…………………………………………..pag.17
SPE for EPA 1664 for Oil and Grease in Waters……………………………………………...pag.18
Organophosphorus Pesticide Monocrotophos in Tap Water by Sepaths SPE/HPLC…………pag.20
Polycyclic Aromatic Hydrocarbons (PAHs) in Tap Water with Sepaths SPE/HPLC…………pag.22
Pyrethroids in Tap Water by Sepaths SPE/HPLC……………………………………………...pag.25
Grease and Oil in Water by Sepaths SPE/Gravimetric Method………………………………..pag.27
Bisphenol A in Water by Extrapid-Rapidisk-HPLC………………………...…………………pag.29
Phthalic Acid Esters in Water by Extrapid-Rapidisk-HPLC…………………………………..pag.31
Carbamate Pesticides in Wheat Flour by Extrapid SPE-HPLC………………………………..pag.33
Sepaths Application book
pag. 3
Determination of Carbaryl in Tap Water by Sepaths-6
SPE/HPLC
LabTech, Inc.
Carbaryl (1-naphthyl methylcarbamate) is a widely used insecticide in the recent 20 years.
The pesticide residue from the environment damages blood system, nerve system, and
reproductive system of human beings. In several countries such as Britain, Australia and
Germany, Carbaryl has been added into prohibited pesticides list.
For the concentration of Carbaryl in drinking water the United State Environmental
Protection Agency (US EPA) have strict limit.
High-performance liquid chromatography (HPLC), the conventional method of Carbaryl
detection, is time-consuming and laborious.
With Sepath®Automated solid-phase extraction (SPE) system and SPE disks, the
efficiency has been greatly increased, saving considerably time and labor.
This study develops one application of Carbaryl detection in water by pretreating the tap
water sample via SPE, and analyzing by HPLC. This method shows a great recovery with
facilitated operation.
1. Experimental
1.1 Instrumentation and Materials
Sepaths-6 Automated SPE System (LabTech Ltd.)
Methanol
Rapidisk C18 47 mm SPE disk (LabTech. Ltd.)
HPLC System coupled with UV detector
Flow rate: 1 mL / min
Mobile phase: Methanol / Water (v / v) 65 / 35
Column: Ultimate C18 (4.6 mm × 250 mm, 5 μm)
Column Temperature: 35° C
Sample Volume: 20 μL
Wavelength: 280 nm
Sepaths Application book
pag. 4
1.2 Method Summary
1) 1000 mL water samples
2) Add 40 mL 0.8 ppm carbaryl standard solution to the sample
3) Fix the sample bottle onto the Sepaths-6 Automated SPE Module with the
Rapidisk C18 SPE disk.
4) Place the 40 mL collection vials into the Sepaths collection window
5) Load and Run the method listed in table 1
6) Once the method is completed, take the collection vials rack with the eluted phases
7) Add Methanol to the eluted phases up to 40 mL
8) Analyze with HPLC system
1.3 SPE Method
Step Solvent Soak Time Volume Dry Time
Prewet 1 Methanol 1 min 5 mL 30 sec
Prewet Methanol 1 min 5 mL 30 sec
Prewet Reagent Water 5 sec 5 mL 2 sec
Prewet Reagent Water 5 sec 5 mL 2 sec
Process Sample
Air Dry 2:00 min
Rinse 1 Methanol 2 min 5 mL 20 sec
Rinse 2 Methanol 30 sec 5 mL 20 sec
Rinse 3 Methanol 30 sec 5 mL 20 sec
Rinse 4 Methanol 30 sec 5 mL 1 min
Table 1. SPE method of carbaryl by Sepaths-6 ® Automated SPE system
The method process takes 35 min to compleatly extract No.6 samples (1 L volume).
Compared with single-channel or manual SPE systems, the efficiency of Sepaths-6
Automated SPE system has been greatly enhanced for the following reasons :
1) 6 samples extracted at the same time
2) No cross contamination
3) Reproducibility of the method
4) High Flow stability/accuracy thanks to Nitrogen positive pressure
Sepaths Application book
pag. 5
2. Results
2.1 Chromatogram of Standard, Control, and Spiked Sample Solutions
Figure 1. HPLC chromatogram of carbaryl standard.
Figure 2. HPLC chromatogram oftap water after SPE.
Sepaths Application book
pag. 7
2.2 Recovery of Carbaryl Spiked Water Samples
To determine the precision of our system, 20 spiked tap water samples were analyzed by
HPLC. 1 L tap water samples were spiked at a concentration of 0.8 mg/L with carbaryl
standard. After extracted by Sepaths-6 Automated SPE system, the extracts were diluted
with methanol to 40 mL.Recovery was calculated by comparing the ratio(s) of analyte peak
areas.
Test Number Standard Spiked
(mg/L)
Analyzed Result
(mg/L) Recovery (%)
Avg. Recovery
(%) RSD
1
0.8
0.6983 87.29
93.50 6.04
2 0.7271 90.89
3 0.7321 91.51
4 0.7244 90.55
5 0.6902 86.27
6 0.7598 94.97
7 0.6833 85.41
8 0.6975 87.19
9 0.7762 97.03
10 0.7781 97.26
11 0.7802 97.52
12 0.7866 98.33
13 0.7349 91.86
14 0.7310 91.37
15 0.7310 89.12
16 0.8217 102.71
17 0.8300 103.75
18 0.7998 99.98
3. Conclusion
This study develops a method of Carbaryl extraction via Sepaths-6 automated SPE system
coupled with HPLC-UV analysis. This method has good recovery (mean recovery 93.5 %)
and the great repeatability (RSD 6.04 %). The results illustrate the reliability of this method
and the efficiency of Sepaths instrument as fast ans easy to use SPE system.
Sepaths Application book
pag. 8
Determination of Organochlorine Pesticides Residue in Tap
Water by Sepaths-6 SPE/GC-ECD
LabTech, Inc.
Organochlorine pesticides is a broad-spectrum, high efficient, inexpensive pesticides,
which were widely used worldwide.
However, the strong stability makes organochlorine pesticides accumulate largely through
the food chain, which eventually influences human beings health. Because of its strong
stability, long half-life, the organochlorinepesticides residue exceeded maximum residue
limit (MRL) happens frequently.
This study develops a method to determine organochlorine pesticides residue in tap water
by using solid phase extraction(SPE) coupled with gas chromatography-electron capture
detection(GC-ECD). This method shows great recovery and easy operation.
1. Experimental
1.1 Instrumentation and Materials
Sepaths-6® Automated SPE System (LabTech. Ltd.)
GC-ECD
DryDisk Solvent Drying System (SDS 101)
Nitrogen Evaporator
Methanol
Ethyl Acetate
n-Hexane
SPE disk
Sepaths Application book
pag. 9
1.2 Method Summary
1) 1000 mL water samples
2) Fix the sample bottle onto the Sepaths-6 Automated SPE Module with the
Rapidisk C18 SPE disk.
4) Place the 40 mL collection vials into the Sepaths collection window
5) Load and Run the method listed in table 1
6) Once the method is completed, take the collection vials rack with the eluted phases
8) Analyze with GC-ECD
1.3 SPE Method
Step Solvent Soak Time Volume Dry Time
Prewet 1 Hexane 3 min 10 mL 0 min
Prewet 2 Methanol 2 min 5 mL 0 min
Prewet 3 Reagent Water 0 min 5 mL 0 min
Process Sample 1 L
Wash 1 Reagent Water -- 10 mL 2 min
Rinse 1 Ethyl Acetate 2 min 7 mL 1 min
Rinse 2 Ethyl Acetate 2 min 7 mL 1 min
Rinse 3 Hexane 2 min 8 mL 1 min
Rinse 4 Hexane 2 min 8 mL 2 min Table 1. Extract method of carbaryl by Sepaths-6 ® Automated SPE system.
The collected extracts from Sepaths-6 Automated SPE system were placed under the
Sepath-C Nitrogen Evaporators,evaporated by N2 till 1.0 mL at 40°C prior to analysis.
1.4 Apparatus
GC-ECD Method :
Column:TM-Pesticide 1 30m×0.53mm×1.0um
Oven Temperature: The initial temperature was 180℃ for 4 minutes, which was increased
to 220℃ at 5℃/min.Then this temperature was held for 6 min.
Injection Temperature: 220℃ ; Detection Temperature: 280℃
Sample Volume: 2μL ; Split Ratio: Splitless
Sepaths Application book
pag. 10
Figure 1. Chromatogram of 8 kinds of Organochlorine Pesticides on GC-ECD.
2. Results and Discussion
2.1 Calibration Curve and Limit of Detection
Figure 2. Calibration curves of 8 kinds of Organochlorine Pesticides.
Sepaths Application book
pag. 11
From these plots, the linear range is 10 ppb-150 ppb. The equations are listed below,
where x is sample concentration, y is peak area.
α -666 y = 9.0287x – 21.465 R2 = 0.9996
β -666 y = 8.3155x – 15.119 R2 = 0.9993
γ -666 y = 2.4953x + 120.71 R2 = 0.9965
δ -666 y = 8.4382x – 8.5691 R2 = 0.9994
P,P-DDT y = 8.655x – 57.722 R2 = 0.9958
O,P-DDT y = 3.2334x + 7.0878 R2 = 0.9960
P,P-DDE y = 6.0085x – 14.612 R2 = 0.9922
P,P-DDD y = 2.8035x + 46.326 R2 = 0.9903
Figure 3. Chromatogram of 8 kinds of Organochlorine Pesticides standard in tap water on GC-ECD.
The accuracy of our method was evaluated by additive recycle experiments. The results of
the organic chlorine pesticide were displayed in Table 1.
Sepaths Application book
pag. 12
Standard (mg/g) Measured (mg/g) Recovery (%)
1 α-666 200 213.98 106.99
203.14 101.57
193.12 96.56
188.99 94.50
197.33 98.67
2 β-666 200 217.55 108.78
209.90 104.95
185.01 92.51
203.17 101.58
197.28 98.64
3 γ-666 200 204.17 102.08
212.70 106.35
175.88 87.94
268.29 134.14
192.87 96.44
4 δ-666 200 225.73 112.86
198.83 99.42
207.51 103.76
226.37 113.19
191.61 95.81
5 P,P-DDT 200 201.37 100.69
223.85 111.92
197.03 98.51
192.93 96.46
194.91 97.45
6 O,P-DDT 200 175.30 87.65
210.62 105.31
208.16 104.08
206.97 103.49
215.77 107.88
7 P,P-DDE 200 215.04 107.52
185.83 92.91
179.48 89.74
209.34 104.67
203.70 101.85
8 P,P-DDD 200 194.17 97.09
209.35 104.67
233.77 116.89
214.22 107.11
194.15 97.07 Table 1. The Recovery of Organochlorine Pesticides in Tap Water.
The water samples were spiked with one kind of organochlorine pesticide, extracted via SPE, then analysis by GC-ECD three times continuously. The results of peak area on the below table No.2 shows the recovery and RSD of 8 kinds of organochlorine pesticides.
Sepaths Application book
pag. 13
Item α-666 β-666 γ-666 δ-666 P,P-DDT O,P-DDT P,P-DDE P,P-DDD
1 3785.448 3009.495 1349.540 2960.282 2129.499 923.274 1871.482 1126.737
2 3844.901 3158.502 1435.250 2942.996 2383.406 972.279 1739.195 1179.389
3 3922.923 3050.534 1313.259 3103.537 2647.132 1084.909 1715.599 1355.31
4 3727.606 3102.758 1475.507 3042.421 2215.406 959.252 1853.438 1279.078
5 3140.690 2531.451 1189.939 2293.325 2145.536 889.795 1705.439 1062.449
RSD
(%) 8.48 8.48 8.26 11.43 9.40 7.65 4.46 9.77
Table 2. The RSD of Organochlorine Pesticides in Tap Water.
Figure 3. Chromatogram of 8 kinds of organochlorine pesticides spiked in tap water on GC-ECD after SPE.
3. Conclusion
This study develops a method for organochlorine pesticides detection by Sepaths-6
automated SPE system, followed by GC-ECD analysis. The mean recoveries of 8 kinds
organochlorine pesticides are 80.19 % - 91.98 %, and the RSD are less than 7.7 %. The
results illustrate the reliability of this method and the efficiency of Sepaths instrument as
fast ans easy to use SPE system.
Sepaths Application book
pag. 14
SPE for Nitrosamines in Water
Introduction:
Due to the carcinogenic nature of nitrosamines at very low levels, new regulations setting
detection limits at PPT (ng/L) levels have been set for nitrosamines in drinking water, milk,
beer, and food products. EPA Method 521 recommends coconut carbon SPE cartridges
and this method can be easily adapted for the analysis of food and beverages.
Reference method:
SPE cartridge: Coconut Carbon, 2g, 6 mL
Analytes: NDMA, NMEA, NDEA, NDPA, NMOR, NPYR, NPIP, NDBA and DPhA
LabTech SPE instrument:
Sepaths (automatic)
SPE method:
Cartridge Condition and wash:
(1) Dichloromethane, 5 mL, condition cartridge then drain to waste
(2) MTBE, 5 mL, condition cartridge then drain to waste
(3) DI water, 5 mL, wash cartridge then drain to waste
Sample Loading:
(1) 1000 mL
(2) Wash sample bottle with 10 mL of DI water
Wash and Eluting:
(1) Dichloromethane, 5 mL, wash cartridge then drain to collect
(2) Dry cartridge for 20 min
(3) Dichloromethane, 5 mL, elution cartridge
Sepaths Application book
pag. 15
SPE for EPA 608 for Organochlorine Pesticides and PCB’s
Reference method:
SPE cartridge: C18, 6 mL
Analytes: Organochlorine Pesticides and PCBs
LabTech SPE instrument:
Sepaths (automatic)
SPE method:
Cartridge Condition and wash:
(1) Reagent Water, 5 mL, wash cartridge then drain to waste
(2) Methanol, 3 mL, wash cartridge then drain to waste
(3) Ethyl acetate, 5 mL, wash cartridge then drain to waste
Sample Loading:
(1) 550 mL
(2) Drying for 5 min
Eluting:
(1) Dichloromethane, 5 mL, soak for 30 sec then drain to collect
Sepaths Application book
pag. 16
SPE for EPA 625 for Semivolatile Organics in Wastewaters
Reference method:
SPE cartridge: C18, 6 mL
Analytes: Organics Compounds
Note: Add 2,5 mL methanol and 2 mL concentrated sulfuric acid to 500 mL of sample
LabTech SPE instrument:
Sepaths (automatic)
SPE method:
Cartridge Condition and wash:
(1) Methanol, 2 mL, wash cartridge then drain to waste
(2) Ethyl acetate and Dichloromethane, 5 mL, wash cartridge then drain to waste
(3) Methanol and water, 10 mL, condition cartridge then drain to waste
Sample Loading:
(1) 550 mL
(2) Drying for 10 min
Eluting:
(1) Ethyl acetate, 5 mL, soak for 30 sec then drain to collect
(2) Dichloromethane, 2 mL, soak for 30 sec then drain to collect
Sepaths Application book
pag. 17
Method for Total Petroleum Hydrocarbon in Water
Reference method:
SPE Disk: DVB sorbent or C18, 47 mm
Analytes: Total Petroleum Hydrocarbons
LabTech SPE instrument:
Sepaths (automatic)
Extrapid (manual)
SPE method:
Disk Conditioning:
(1) Methylene Chloride, 7 mL, soak for 1 min then drain to waste
(2) Methanol, 7 mL, soak for 1 min then drain to waste
Keep the C18 disk, if used, wet during and after conditioning
Sample Loading:
(1) 500 mL -1000 mL
(2) Dry for 5 min
Eluting:
(1) Acetone, 7 mL, rinses the empty bottle then transferred to the disk, soaks for 0.5 min
then drain to collect
(2) Methylene Chloride, 7 mL, soak for 1 min then drain to collect
(3) Methylene Chloride, 7 mL, soak for 1 min then drain to collect
(4) Methylene Chloride, 7 mL, soak for 2 min then drain to collect
Sepaths Application book
pag. 18
SPE for EPA 1664 – Oil and Grease in Waters
Introduction:
This method describes how to apply SPE for the EPA 1664A using LabTech equipment for
manifold SPE (Extrapid) or automatic SPE (Sepaths). SPE is permitted from the EPA
method as alernative to liquid-liquid hexane extraction ensuring up to 40% of solvent
saving and up to 50% of time saving (using Sepaths compared to LLE). The extract is
dried with sodium sulfate, hexane is evaporated and the residue is weighed and reported
in mg/L as HEM (N-Hexane Extractable Material)
Reference method:
SPE disks: LabTech, C18, 47mm
Analytes: N-Hexane Extractable Material (HEM)
Note : The pH level of the sample solution must be adjusted to 2 with acid solution
before to perform the SPE process
LabTech SPE instrument:
Sepaths (automatic)
Extrapid (manifold)
SPE method:
System and cartridge Pre-condition
(1) N-Hexane, 20 mL, precondition disks then drain to waste
(2) N-Hexane, 20 mL, second precondition then drain to waste and Dry for 1 minute
Disks Condition and Wash:
(1) Methanol, 10 mL, condition disks, soak for 1 minute then drain to waste
(2) DI water, 30 mL, wash disks then drain to waste
Note : Do not allow the disk to dry during Condition ad Wash steps
Sepaths Application book
pag. 19
Sample Loading:
(1) 1000 mL of sample solution adjusted to pH 2
Dry and Eluting:
(1) Dry disks for 2 minutes
(2) Wash sample bottle with 10 mL of Hexane, soak disks for 2 minutes then collect in the
elution position
(3) Repeat the above step
(3) Hexane, 10 mL, elute disks then dry for 5 minutes
The eluate is then dried using Anhydrous Sodium Sulfate. Add 5 g of Sulfate on a funnel
with glass wool on the bottom, then pour the eluate on the funnel and collect in a
previously weighed clean vial. Rinse the funnel and the Sodium Sulfate with 10 mL of
Hexane and collect in the same vial.
The last step is the Hexane evaporation. When Hexane is evaporated, weight the vial and
calculate the HEM quantity in mg/L
Sepaths Application book
pag. 20
Determination of Organophosphorus Pesticide
Monocrotophos in Tap Water by Sepaths Automated SPE
extraction System
LabTech, Inc.
This work was to evaluate Sepaths system’s performance in SPE extraction of
organophosphorus pesticide Monocrotophos in tap water, as required by a water company
of Taiwan. Tap water samples were spiked with Monocrotophos and the extractions
performed using DVB disks. The determination of the analyte was performed by HPLC.
1. Experimental
1.1 Instrumentation and Materials
Sepaths-6 Automated SPE System (LabTech Ltd.)
Methanol
Ethyl acetate
DVB SPE disk
HPLC-UV System
1.2 Method Summary
1) 3 x 1000 mL tap water samples
2) The water samples are spiked with 10 ppb of Monocrotophos
3) Fix the sample bottle onto the Sepaths-6 Automated SPE Module with the DVB SPE disks
4) The extracts are concentrated near to dry and made up to 1.0 ml using HPLC mobile
phase
5) Final analysis is by HPLC-UV.
Sepaths Application book
pag. 21
1.3 SPE Method
Step Solvent Volume
(mL)
Soak
(min)
Soak
(sec) Cycle Collection
Dry
(min)
Dry
(sec)
Conditioning Ethyl acetate 5 2 30 1 0 0
Conditioning Methanol 5 2 30 1 0 0
Conditioning Methanol 5 0 30 1 0 0
Conditioning Water 10 0 30 1 0 0
Sample Loading 1000 0 0 1 1 0
Drying 0 0 1 3 30
Eluting Ethyl acetate 10 1 30 1 1 0 30
Eluting Ethyl acetate 10 1 30 1 1 0 30
Eluting Ethyl acetate 10 1 30 1 1 0 30
Table 1. SPE method by Sepaths-6 ® Automated SPE system
The method process takes 1 hour to compleatly extract No.3 samples (1 L volume).
Compared with single-channel or manual SPE systems, the efficiency of Sepaths
Automated SPE system has been greatly enhanced for the following reasons :
1) 1 to 6 samples extracted at the same time
2) No cross contamination
3) Reproducibility of the method
4) High Flow stability/accuracy thanks to Nitrogen positive pressure
2. Results
2.1 Recovery of spiked Monocrotophos in tap water samples
HPLC tr
(min)
Recovery
(%) #1
Recovery
(%) #2
Recovery
(%) #3
Average (%)
RSD (%)
7.58 88.6 90 95 91.2 3.68
Table 1. Recoveries and RSD
3. Conclusion
This study develops a method of Organophosphorus pestic extraction via Sepaths
automated SPE system coupled with HPLC-UV analysis. This method has good recovery
and the great repeatability (RSD 3.68 %). The results illustrate the reliability of this method
and the efficiency of Sepaths instrument as fast ans easy to use SPE system.
Sepaths Application book
pag. 22
Determination of Polycyclic Aromatic Hydrocarbons in
Tap Water with Sepaths SPE-HPLC
LabTech, Inc.
This work was to evaluate Sepaths system’s performance in SPE extraction of Polycyclic
Aromatic Hydrocarbons (PAHs) in tap water. Tap water samples were spiked with PAHs
and the extractions performed using C18 disks. The determination of the analyte was
performed by HPLC.
1. Experimental
1.1 Instrumentation and Materials
Sepaths-6 Automated SPE System (LabTech Ltd.)
Methanol
n-Hexane
Methylene chloride
C18 SPE disk
HPLC-UV System
EV311 Rotary Evaporator (LabTech Ltd.)
1.2 Method Summary
1) 6 x 500 mL tap water samples
2) The water samples are spiked with 10 ppb of PAHs and mixed with 88 mL methanol
3) Fix the sample bottle onto the Sepaths-6 Automated SPE Module with the C18 SPE disks
4) The extracts are dehydrated and concentrated near to dry and made up to 2.0 ml using
HPLC mobile phase
5) Final analysis is by HPLC-UV.
Sepaths Application book
pag. 23
1.3 SPE Method
Table 1. SPE method by Sepaths-6 ® Automated SPE system
2. Results
2.1 Recovery of 16 PAHs sp in tap water samples
Recovery(%) 1 2 3 4 5 6 Average RSD(%)
Naphthalene 72 81 75 78 84 70 77
83
7.0
4.6 Acenaphthylene 76 86 83 85 80 85
Acenaphthene 98 101 92 100 97 99 98 2.3
Fluorene 117 127 122 118 124 112 120 3.6
Phenanthrene 86 95 91 95 94 96 93 3.1
Anthracene 90 99 112 98 93 95 98 5.3
Fluoranthene 99 94 96 102 91 104 98 4.1
Pyrene 90 76 87 80 84 89 84 5.1
Benzo (a) anthracene 82 87 95 98 99 86 91 6.8
Chrysene 82 83 85 90 80 94 86 4.9
Benzo (b) fluoranthene 86 84 83 84 79 78 82 3.1
Benzo (k) fluoranthene 70 82 79 75 76 79 77 4.1
Benzo (a) pyrene 87 89 90 82 94 95 89 3.9
Dibenzo (a, H) anthracene 76 84 77 76 80 84 80 4.0
Benzo (GHI) Perylene 86 95 88 84 84 91 88 3.8
Indeno (123-cd) pyrene 87 78 84 86 81 83 83 3.0
Table 2. Recoveries and RSD
Step Solvent
Volum
e
(mL)
Soak
(sec) Pressure
Dry
(sec)
Conditioning n-Hexane 10 30 10 Psi 0
Conditioning Methylene chloride 10 30 10 Psi 0
Conditioning Methanol 10 30 10 Psi 0
Conditioning DI Water 10 0 10 Psi 0
Sample Loading 500 0 6 mL/min 0
Washing 5% Methanol 10 30 10 Psi 30
Eluting Methylene chloride 8 30 10 Psi 0
Eluting Methylene chloride 8 30 10 Psi 0
Eluting Methylene chloride 8 30 10 Psi 30
Eluting Methylene chloride 8 30 10 Psi 30
Sepaths Application book
pag. 24
3. Conclusion
The high recoveries and low RSDs show a reliable method to enrich very low
concentration of PAHs from water samples in a limited period with Sepaths. In this way, it
is very easy and rapid to conduct a water test project, which can be very time-consuming
with traditional method.
Sepaths Application book
pag. 25
Determination of Pyrethroids in Tap Water by Sepaths
Automated SPE extraction System and HPLC
LabTech, Inc.
This work was to evaluate Sepaths system’s performance in SPE extraction of Five
Pyrethroids, including fenpropathrin, cyhalothrin, deltamethrin, fenvalerate and permethrin,
are spiked into small volume water samples and extracted by Sepaths SPE with SPE
cartridges then analyzed by HPLC to show the a rapid way to determine insecticides in
water.The determination of the analyte was performed by HPLC.
1. Experimental
1.1 Instrumentation and Materials
Sepaths-6 Automated SPE System (LabTech Ltd.)
Methanol
C18 SPE 500 mg 6 mL cartridge (LabTech Ltd.)
ET nitrogen concentrator (LabTech Ltd.)
HPLC-UV System
1.2 Method Summary
1) 5 x 2 mL D.I. water samples spiked with 2 ppm of 5 Pyrethroids including Fenpropathrin,
Cyhalothrin, Deltamethrin, Fenvalerate and Permethrin.
2) Run the samples on Sepaths using 500 mg 6 mL C18 SPE cartridges
3) The extracts are concentrated to 1 mL
4) Analyzed by HPLC with UV detector at 205 nm.
Sepaths Application book
pag. 26
1.3 SPE Method
Step Solvent V
(mL)
Soak
(min) Cycle Dry
(min)
Conditioning Methanol 5 1 1 0
Conditioning Water 5 0 1
Sample Loading 2 0 1 0
Rinsing Water 10 0 1 10
Eluting (through sample bottle) Methanol 10 1 1 1
Table 1. SPE method by Sepaths-6 ® Automated SPE system
2. Results
2.1 Recovery of spiked Pyrethroids in water samples
No. tr
(min)
SPE-1 SPE-2 SPE-3 SPE-4 SPE-5 Average
(%)
RSD(%)
Fenpropathrin 10.170 87.1 94.0 86.1 84.5 92.3 88.8 4.61
Cyhalothrin 11.902 85.2 103.7 96.2 95.2 81.6 92.4 9.65
Deltamethrin 12.763 81.6 89.1 88.5 86.6 75.7 84.3 6.70
Fenvalerate 13.517 89.1 92.1 100.9 105.7 92.4 96.0 7.25
Permethrin 15.102 93.7 92.0 96.7 89.1 91.0 92.5 3.11
Table 2. Recoveries and RSD
3. Conclusion
This study develops a method for Pyrethroids analysis via Sepaths automated SPE
system coupled with HPLC. The results illustrate the reliability of this method and the
efficiency of Sepaths instrument as fast and easy to use SPE system.
Sepaths Application book
pag. 27
Sepaths Solid-Phase Extraction system for Determination
of Grease and Oil in Water by Gravimetric Method
LabTech, Inc.
This experiment is a preliminary test to show Sepaths’ capability to handle water samples
with high level grease and oil. Hexadecane was used as a grease standard.
1. Experimental
1.1 Instrumentation and Materials
Sepaths-6 Automated SPE System (LabTech Ltd.)
Carbon tetrachloride
Oil and grease SPE disk 47mm (Horizon Tech. Ltd.)
Hotplate (LabTech Ltd.)
Analytical balance
1.2 Method Summary
1) 6 x 1000 mL tap water are used for the experiment
2) 100 ppm hexadecane is spiked into 5 samples, and 1 sample is left as blank
3) Run the 6 sample using Pacific oil and grease disk
4) Evaporate the solvents from collected extracts until constant weight
5) Weighing samples
Sepaths Application book
pag. 28
1.3 SPE Method
Step Solvent Volume
(mL)
Soak
(min)
Soak
(sec) Cycle Collection
Dry
(min)
Dry
(sec)
Initializing 1 30
Conditioning CCl4 10 0 30 1 0 0
Sample Loading 1000 0 0 1 1 0
Eluting (through sample bottle) CCl4 10 1 30 1 1 1 0
Eluting (through sample bottle) CCl4 10 1 30 1 1 1 0
Eluting (bypass sample bottle) CCl4 10 1 0 1 1 1 0
Eluting (bypass sample bottle) CCl4 10 1 0 1 1 4 0
Table 1. SPE method by Sepaths-6 ® Automated SPE system
2. Results
The weight of blank sample is zero, while the spiked samples’ data are listed in Table 2.
Al plate weight
(g)
Al plate and grease weight
(g)
Grease weight
(g)
Recovery
(%)
RSD
(%)
Standard 1 2.5904 2.6497 0.0593
3.5
Standard 2 2.5738 2.6325 0.0587
average 0.0590
Sample 1 2.5731 2.6366 0.0635 107.6
Sample 2 2.5684 2.6263 0.0579 98.1
Sample 3 2.5693 2.6280 0.0587 99.4
Sample 4 2.5801 2.6413 0.0612 103.4
Sample 5 2.5793 2.6363 0.0570 96.6
Average 0.05966 101.1
Table 2. Weight, recovery and RSD
3. Conclusion
Sepaths is a useful tool in determining grease and oil in water for its tightness that isolate
samples and solvents from ambient air, so that avoid the potential pollution of samples and
solvents from air-borne hydrocarbon vapor, especially for oil plant lab.
.
Sepaths Application book
pag. 29
Determination of Bisphenol A in Water by Extrapid-
Rapidisk-HPLC
LabTech, Inc.
This experiment evaluate the Extrapid manual SPE equipment for extraction of Bisphenol
A from large volume water samples.
1. Experimental
1.1 Instrumentation and Materials
Extrapid manual SPE equipment (LabTech Ltd.)
Rapidisk C18 SPE disks (LabTech Ltd.)
HPLC instrument
1.2 Method Summary
1) 3 x 300 mL tap water samples are spiked with 94 ppb Bisphenol A then add 40 mL
methanol
2) 3 x 500 mL tap water samples are spiked with 59 ppb Bisphenol A then add 40 mL
methanol
3) Run the samples on Extrapid using Rapid C18 SPE disks
4) The extracts are made up to 40.0 mL with water and analyzed by HPLC
Sepaths Application book
pag. 30
1.3 SPE Method
Step Solvent Soak Dry
Conditioning Methanol 10ml 1min
Conditioning Reagent water 10ml 1min
Sample Loading
Rinsing Reagent water 10ml 30sec 1min
Eluting Methanol 10ml 1min 1min
Eluting Methanol 10ml 1min 1min
Eluting Methanol 10ml 2min 1min
Table 1. SPE method by Extrapid
2. Results
The recoveries and RSDs results are listed in Table 2.
Test group Recovery (%) Rsd
300ml—A 86.4
0.59% 300ml—B 85.3
300ml—C 86.5
500ml—A 83.8
0.62% 500ml—B 84.9
500ml—C 83.2
Table 2. Recovery and RSD
3. Conclusion
The use of Extrapid for the analysis of Bisphenol A in tap water shows an excellent
repeatability. However the methods is still under evaluation and higher recovery rate is
expected with future parameters optimization.
Sepaths Application book
pag. 31
Determination of Phthalic Acid Esters in Water by
Extrapid-Rapidisk-HPLC
LabTech, Inc.
This experiment evaluate the Extrapid manual SPE equipment for extraction of Phthalic
Acid Esters (PAEs) from large volume water samples.
1. Experimental
1.1 Instrumentation and Materials
Extrapid manual SPE equipment (LabTech Ltd.)
Rapidisk C18 SPE disks (LabTech Ltd.)
HPLC instrument
1.2 Method Summary
1) 3 x 1000 mL tap water samples are spiked with 40 ppb of 5 PAEs species
2) Run the samples on Extrapid using Rapid C18 SPE disks
3) The extracts are made up to 40.0 mL with water and analyzed by HPLC
Sepaths Application book
pag. 32
1.3 SPE Method
Step Solvent Soak Dry
Conditioning Methanol 10ml 30sec
Conditioning Reagent water 10ml 30sec
Sample Loading
Rinsing Reagent water 10ml 30sec 1min
Eluting Methanol 15 ml 1min 1min
Eluting Methanol 15 ml 1min 1min
Table 1. SPE method by Extrapid
2. Results
The recoveries and RSDs results are listed in Table 2.
PAEs
Recovery DMP DEP DBP DEHP DNOP
Sample 1 99.8% 97.3% 98.9% 98.4% 97.8%
Sample 2 90.0% 92.5% 91.0% 97.4% 95.7%
Sample 3 90.0% 93.7% 92.5% 94.4% 97.1%
Average 93.27% 94.5% 94.13% 96.73% 96.87%
RSD 5.7% 2.5% 4.2% 2.1% 1.1%
Table 2. Recovery and RSD
3. Conclusion
PAEs is a kind of highly concerned pollutant in environment and food safety. Extrapid
shows satisfying performance and analytical results in the extraction of PAEs from water
samples.
Sepaths Application book
pag. 33
Extrapid SPE-HPLC for Determination of Carbamate
Pesticides in Wheat Flour
LabTech, Inc.
This experiment evaluate the Extrapid manual SPE equipment for extraction and cleanup
of Five carbamate pesticides species from wheat flour. After been extracted the samples
are concentrated by MultiVap parallel evaporator and analyzed by HPLC.
1. Experimental
1.1 Instrumentation and Materials
Extrapid manual SPE equipment (LabTech Ltd.)
Florsil SPE cartridge, 500 mg, 6mL
Graphite carbon black SPE cartridge, 500 mg, 6mL
MultiVap, parallel concentrator (LabTech Ltd.)
HPLC instrument
1.2 Method Summary
1) Weigh 5 g wheat flour into a 50 mL centrifugal tube, add 20mL acetonitrile,
homogenized for 1 min, centrifuge at 4000 r/min for 3 min
2) Take the upper solvent into another 50 mL centrifugal tube
3) Repeat the solvent extraction with 10 mL more acetonitrile and combine the extracts
4) Rinse the acetonitrile phase with 10 mL n-hexane
5) Concentrate the acetonitrile phase to near dry and make up to 2.0 mL with acetone/n-
hexane (3/7, v/v)
6) Run the samples on Extrapid using serial carbon black (upper) and florsil (lower) SPE
cartridges
7) The extracts are concentrated to near dry with MultiVap and made up to 2.0 mL with
HPLC mobile phase
8) Final analysis is by HPLC gradient
Sepaths Application book
pag. 34
1.3 SPE Method
Step Solvent Soak Dry
Conditioning Acetone/N-Hexane (3/7, v/v), 20 ml 30sec
Sample Loading
Rinsing Acetone/N-Hexane (3/7, v/v), 2 ml 30sec
Eluting Acetone/N-Hexane (3/7, v/v), 30ml 1min 1min
Table 1. SPE method by Extrapid
2. Results
The recoveries and RSDs results are listed in Table 2.
No. tr
(min)
SPE-1 SPE-2 SPE-3 SPE-4 SPE-5 Average
(%) RSD(%)
Aldicarb 8.190 102.8 90.7 106.2 103.1 105.2 101.6 6.16
Metolcarb 9.707 82.3 85.4 87.7 89.6 86.1 86.2 3.16
Carbofuran 11.938 98.8 93.3 86.0 85.9 99.9 92.8 7.24
Carbaryl 14.597 105.0 103.4 95.1 102.4 108.1 102.8 4.68
Isoprocarb 21.712 89.5 89.4 86.7 81.4 87.1 86.8 3.79
Table 2. Recovery and RSD
3. Conclusion
The good results demonstrate that Extrapid is reliable platform to conduct food safety SPE
extractions.