Application of fabric phase sorptive extraction/gas...

www.jss-journal.com Page 1 Journal of Separation Science

Received: 08 14, 2018; Revised: 11 29, 2018; Accepted: 12 03, 2018

This article has been accepted for publication and undergone full peer review but has not been

through the copyediting, typesetting, pagination and proofreading process, which may lead to

differences between this version and the Version of Record. Please cite this article as doi:

10.1002/jssc.201800854.

This article is protected by copyright. All rights reserved.

Application of Fabric Phase Sorptive Extraction/Gas Chromatography-Mass

spectrometry for the Determination of Organophosphorus pesticides in Selected

Vegetable Samples

Ramandeep Kaur1, Ripneel kaur

1, Susheela Rani

1, Ashok Kumar Malik

1,*, Abuzar Kabir

2,**

and Kenneth G. Furton2

1Department of Chemistry, Punjabi University, Patiala-147002, India

2International Forensic Research Institute, Department of Chemistry and Biochemistry,

Florida International University, Miami, FL 33193, USA

Running Title: Fabric Phase Sorptive Extraction/GC-MS method for organophosphorus

pesticides

Corresponding authors:

* Tel. (+91) 175-3046598; Fax: (+91) 175-2283073; E-mail: [email protected]

(A.K. Malik)

** Tel. (+1) 305 348 2396; Fax: (+1) 305 348 4172; E-mail: [email protected] (A. Kabir)

Abbreviations: CPE, Cloud point extraction; DLLME, dispersive liquid-liquid

microextraction; FPSE, Fabric Phase sorptive extraction; FPSE/GC-MS, Fabric phase

sorptive extraction/gas chromatography-mass spectrometry; MSB-LPME, Magnetic solvent

bar liquid-phase microextraction; MSPE, Magnetic solid phase extraction; MRLs, Maximum

Residue Limits; MIP, Molecularly imprinted polymer; OPPs, Organophosphorus pesticides;

SDME, Single-drop microextraction; SPME, Solid phase microextraction; SBME, Stir bar

microextraction; US-EPA, United States Environment Protection Agency.

https://doi.org/10.1002/jssc.201800854



http://crossmark.crossref.org/dialog/?doi=10.1002%2Fjssc.201800854&domain=pdf&date_stamp=2019-01-01


This article is protected by copyright. All rights reserved. 2

Keywords: Fabric Phase Sorptive Extraction; Green Analytical Chemistry;

Organophosphorus pesticides; Pesticides Residues; Food Safety

ABSTRACT

In the present work, a high-efficiency and solvent minimized microextraction

technique, fabric phase sorptive extraction followed by GC-MS analysis is proposed

for the rapid determination of four organophosphorus pesticides (terbufos, malathion,

chlorpyrifos and triazofos) in vegetable samples including beans, tomato, brinjal and

cabbage. Fabric phase sorptive extraction combines the beneficial features of sol-gel

derived microextraction sorbents with the rich surface chemistry of cellulose fabric

substrate, which collectively form a highly efficient microextraction system. Fabric phase

sorptive extraction membrane, when immersed directly into the sample matrix, may

extract target analytes even when high percentage of matrix interferents is present.

The technique also greatly simplifies sample preparation workflow. Most important

fabric phase sorptive extraction parameters were investigated and optimized. The

developed method displayed good linearity over the concentration range 0.5-500

ng/g. Under optimum experimental conditions, the limits of detection were found in the

range of 0.033 ng/g to 0.136 ng/g. The relative standard deviations for the extraction of

organophosphorus pesticides were <5%. Subsequently, the new method was applied to

beans, tomato, brinjal and cabbage samples. The results from the real sample analysis

indicate that the method is green, rapid and economically feasible for the determination

of organophosphorus pesticides in vegetable samples .



1 INTRODUCTION

The ever growing human population with increased food demands has led to the spurious use

of pesticides. Organophosphorus pesticides (OPPs) are one of the most widely used

categories of pesticides which gained popularity after ban imposed on persistent

organochlorine pesticides in 1970s [1,2]. Their short persistence, lower price, highly

effectiveness and biodegradable nature made them much popular. They are found to be

highly to moderately toxic by the United States Environment Protection Agency (US-EPA)

[3, 4]. These emerging pollutants are suspected to be endocrine disrupting chemicals and

carcinogens. In the recent years, the overuse of OPPs has put human health and food security

at a major risk [5, 6] Their mode of action is by the inhibition of acetyl cholinesterase which

in turn block transmission of nerve impulse across synapses [7, 8]. Excessive use of OPPs

leads to their residues being found in ground water, fruits, vegetables and drinking water. It

has been reported that intoxication of OPPs is one of the major toxic incidents related to OPP

residues in cereals, vegetables and fruits [9, 10]. The Maximum Residue Limits (MRLs)

established by the European Union for OPPs in fruits and vegetables is 0.01-0.3 mg/kg [11,

12]. Due to health hazard associated with their accumulation in human tissues, it is critical to

develop simple, low cost and environmental friendly sample pre-treatment method possessing

high extraction efficiency for the analysis of OPPs in vegetable samples.

Sample preparation plays pivot role in the isolation, clean up and preconcentration of the

target analytes from the complex sample matrices prior to chromatographic analysis. Besides

preconcentrating the target analyte, it also removes the interfering substances from sample

matrix leading in improved selectivity and specificity of the analysis. Unlike the

conventional solvent techniques such as liquid-liquid extraction (LLE) and solid phase

extraction (SPE) which were solvent and time consuming, the current trend for the sample



preparation approach leans towards miniaturized sorbent based extraction techniques [13].

The various sample pretreatment methods presently used for analysis of OPPs in food and

environmental samples include magnetic solvent bar liquid-phase microextraction (MSB-

LPME) [14], magnetic solid phase extraction (MSPE) [15-17], dispersive liquid-liquid

microextraction (DLLME) [18], solid phase microextraction (SPME) [19], dynamic

microwave assisted extraction (DMAE) [20], air-assisted liquid-liquid extraction [21] , cloud

point extraction (CPE) [22], molecularly imprinted polymers (MIPs) [23], single-drop

microextraction (SDME) [24] and stir bar microextraction (SBME) [25] are noteworthy.

Although these techniques are congruent with green chemistry principles as they not only use

small amount of sorbent but also reduced toxic organic solvent consumption making them

cost effective and environmentally friendly. However, improvement in longer extraction time

and expensive equipment remain as major sample preparation challenges prior to

chromatographic analysis.

In order to overcome the problems associated with time consuming and multistep sample

preparation techniques, Kabir et al. [26] recently presented a sorbent based sample

preparation technique known as fabric phase sorptive microextraction (FPSE). The new

approach has candidly integrated the extraction principles of SPE and SPME and greatly

contributed to the sorbent-based sample preparation due to its simplicity, rapidity, and

increased extraction yields, low cost and low solvent consumption [27-29]. FPSE has several

advantages such as large specific surface area, uniform microporosity, pore volume, fast

adsorption and ease of handling. The more porous surface structure of the media provides

higher surface area resulting to higher extraction efficiency with shorter desorption time. Its

ability to directly preconcentrate the target analytes from complex matrices in presence of

matrix interferences such as particulate debris makes FPSE prominent among the practicing



analytical chemists [30, 31]. Such distinct features make FPSE versatile tool in sample

preparation and it has been efficiently used for analysis of analytes in various matrices [32-

34].

The aim of the present study is to evaluate the viability of FPSE media for the selective

analysis of commonly applied organophosphorus pesticides on vegetables. Herein, we

developed a simple but highly selective analytical method using FPSE as sample preparation

technique followed by GC-MS for extraction of OPPs including terbufos, malathion,

chlorpyrifos and triazofos from beans, tomato, brinjal and cabbage samples. Sol-gel

Carbowax 20 M sorbent coating on cellulose fabric was employed for the extraction of OPPs

which can selectively interact with specific functional moieties of the analytes. As a result,

enhanced sensitivity with reduced matrix interference was achieved. The method parameters

were systematically studied and optimized. The developed method proved to be highly

sensitive and reproducible for this important class of pesticides.

2 MATERIALS AND METHODS

2.1 Reagents, solvents and material

Certified individual pesticide standards chlorpyrifos, malathion, terbufos, triazofos were

obtained from Sigma Aldrich (Bangalore, India) and were stored at −4°C. Analytical grade

methanol and acetonitrile were supplied by Merck (Mumbai, India). Water was deionized

(Riviera, SCHOTT DURAN, Mainz, Germany) and filtered using 0.45 µm Nylon 6,6

membranes (Rankem, New Delhi, India) filtration assembly ( Perfit, India). Individual stock

standard solutions (1 mg/L) were prepared by dissolving an accurate weight of each pesticide

in acetonitrile. Working standard solutions were prepared by serial dilution of the individual

stock with acetonitrile. An intermediate stock standard mixture was prepared by mixing the



appropriate volumes of individual stock solutions and diluted with highly purified water to a

required concentration.

2.2 Instrumentation

The pesticide analyses were performed using GC–MS QP 2010 plus (Shimadzu, Kyoto,

Japan). Chromatographic separation was conducted with Rtx-1MS capillary column (30

m×0.25 mm I.D., film thickness of 0.25 m, J & W Scientific, Folsom, CA, USA). Helium

(purity≥99.999%) was used as carrier gas at a constant flow of 1.0 mL/min. The temperature

program was set initially at 100°C for 1 min; ramp to 200°C at a rate of 15°C min−1

; 250°C at

10°Cmin−1

and finally to 300°C at a rate of 5°C min−1

with total run time of 22.66 min.

Injector temperature was maintained at 280°C, and the injection volume was 1.0 µL in a

splitless mode. Mass spectrometric parameters: electron impact ionization mode with an

ionizing energy of 70 eV, injector temperature 250°C interface temperatures 230°C, ion

source temperature 200°C. Full-scan MS data were acquired in the range of m/z 50–500 to

obtain the fragmentation spectra of the analytes. The Quantification of OPPs was performed

in the selected ion monitoring (SIM) mode and specific ions were chosen for each analyte

(qualitative and quantitative) as shown in Table1.

2.3 Sample collection and preparation

Vegetable samples (beans, cabbage, tomato and brinjal) were purchased from a local

supermarket in Patiala (Punjab, India). They were washed with ultrapure water and then

chopped to small pieces and further homogenized with a laboratory homogenizer. The

individual homogenized vegetable mixture (20.0 g) was added to a 50 mL centrifugal tube

containing 10 mL of water-MeOH (1:10) mixture. It was then vortexed vigorously for 2 min

followed by centrifugation for 5 min at 4000 rpm. The supernatant was collected and filtered



through 0.45 mm filter paper. Consequently, the mixture was transferred to a 50 mL

volumetric flask and diluted with ultrapure water to reach the mark. It was stored in dark at

4°C until used for analysis [35].

2.4 Fabric phase extraction procedure

In order to condition and equilibrate, the FPSE media was rinsed with ethyl acetate followed

by water and dried in air water prior to use. Extraction was carried as follows: the FPSE

media was first immersed in a glass vial with 10 mL sample solution and Teflon coated

magnetic bed under constant magnetic stirring for a prescribed time. Subsequently, the media

was taken out from the sample carefully and gently dried with a lint free filter paper. Finally,

the media was directly placed in a glass vial containing the desorbing solvent for 10 min. The

eluent with target analytes was then filtered with syringe filters before injection to the GC-

MS system. After desorption, the extraction media was washed repeatedly with ethyl acetate

and water for removal of any possible residual analyte or other substances.

3 RESULTS AND DISCUSSION

3.1 Optimization of fabric phase extraction

To evaluate the FPSE/GC-MS procedure, several parameters that can affect the

microextraction recovery of four OPPs were optimized. The optimization process is based on

one-at-a-time approach that is varying one parameter at a time while keeping the other

parameters constant. The batch studies were performed using 10 mL of aqueous sample

spiked with 10 ng/mL of OPPs. Three different sol-gel sorbent coated FPSE media were

evaluated including: sol-gel Carbowax 20M (sol-gel CW 20M), sol-gel poly(tetrahydrofuran)

(sol-gel PTHF) and sol-gel poly(dimethyl siloxane) (sol-gel PDMS). Carbowax 20M is a

polar polymer, poly(tetrahydrofuran) is of medium polarity and poly(dimethyl siloxane) is a



nonpolar polymer. Accordingly, poly(tetrahydrofuran) or poly(dimethyl siloxane) should

have offered higher affinity towards the target analytes possesing logKow values ranging

from 2.35 to 6.51. However, sol-gel Carbowax 20 M media demonstrated the best recoveries

among all the sorbent chemistries evaluated. It should be noted that the selectivity and

extraction recovery of FPSE media depend combinedly on: (1) the polarity of the organic

polymer; (2) the absence or presence of an organic ligand on the inorganic precursor and the

nature of the ligand; (3) hydrophilicity or hydrophobicity of the fabric substrate. All the sol-

gel sorbents were prepared using the same sol-gel precursor, methyl trimethoxysilane and

hydrophilic 100% cotton cellulose fabric support. Unlike SPME, analyte extraction in FPSE

is primarily governed by functional interactions between the FPSE media coated with sol-gel

sorbent and the analytes. The selected OPPs are either medium polar or nonpolar. However,

the all possess high number of hydrogen bond donor sites (from 5 to 8, depending on the

analyte). Carbowax 20M, the organic polymer component of sol-gel CW 20M coating

possesses 2 hydrogen bond donor sites in each unit of ethylene glycol. On the other hand,

both dimethylsiloxane and tetrahydrofuran, the building blocks of sol-gel PDMS and sol-gel

PTHF each possess 1 hydrogen bond donor site per unit of monomer. Higher number of

hydrogen bond donor sites combined with other intermolecular interactions may have

contributed to the superior selectivity and higher recovery exerted by sol-gel CW 20M coated

FPSE media. As such, sol-gel CW 20M coated FPSE media was selected as the suitable

FPSE media for the selected OPPs and subsequently used in FPSE method optimization

exercises.

3.1.1 Effect of stirring rate

A significant influence was observed in the peak area by variation in the stirring rate. The

effect of the stirring rate on the extraction efficiency was studied within the interval 300–



1200 rpm. There was an increase in the recovery with the stirring rate up to 1200 rpm.

Stirring enables a continuous exposure of the extraction surface by the sample with increased

analyte transfer from the bulk solution to the extracting phase resulting in enhanced recovery.

Thus, 1200 rpm was ultimately selected as the optimum stirring rate [Fig. 1(a)].

3.1.2 Effect of extraction time

As FPSE is an equilibrium based technique, the amount of analytes extracted depends upon

the adequate contact time between analytes and the adsorbent. This is influenced by the

physical and chemical properties of the adsorbent. Extraction time is increased to obtain the

highest recovery until equilibrium is reached. To achieve the highest possible extraction

recovery for the analytes, the effect of the extraction time varying from 5 to 35 min was

evaluated. The result showed that the extraction efficiency for all OPPs increased from 5 to

25 min gradually and remained constant after 25 min revealing the rapid mass transfer of

analytes from the aqueous medium to an adsorbent as shown in [Fig 1(b)]. Hence, 25 min

was selected as the extraction time for subsequent analysis.

3.1.3 Effect of pH on extraction efficiency

The charge and stability of an analyte in a given solution is highly affected by pH of the

solution which influences the adsorption of an analyte on the adsorbent. The effect of pH on

recovery was conducted by varying values ranged from 2 to 10 adjusting with HCl or NaOH

(n=3). The results showed no significant variation in the extraction recovery of the analytes

in the range tested besides the fact that OPPs are susceptible to slow hydrolysis under

alkaline conditions. Hence, the signal remained almost constant until pH 8 and then

decreased due to hydrolysis of OPPs. Additionally, the variation in the pH value did not

affect the charge on the adsorbent. The interaction between analytes and FPSE media was



proved to be pH independent as depicted in [Fig 1(c)]. Thus, rationally, there is no need to

adjust pH of the sample solution and the procedure was done with distilled water only having

pH near to 6.

3.1.4 Effect of salt addition

The addition of salt can either enhance the extraction efficiency with salting-out effect by

decreasing the solubility of the analyte in the aqueous solution or lower the extraction due to

mass transfer difficulty from aqueous solution to the adsorbent. In this study, the effect of ion

strength on the extraction efficiency of the analytes was investigated by adding different

concentrations (0, 1, 2.5, 5, 10 and 15%, (w/v) of NaCl into the standard working solution

with three replicates at each point. The extraction efficiency remained constant between 0 to

2.5 %. Thereafter it decreased sharply with an increase of NaCl in the solution. Therefore, no

salt was added in the subsequent experiments [Fig. 1(d)]

3.1.5 Optimization of desorption conditions

The desorption conditions including the desorption solvent, the desorption volume and

desorption time were evaluated for the extraction of OPP. The appropriate selection of the

organic solvent is of great importance to elute the analytes effectively from the analyte with

enhanced recovery. In this case, four common solvents including methanol, ethyl acetate,

acetone and hexane were investigated to obtain maximum recovery of the analytes of interest

on the FPSE media with fixed volume (300 µL). The results indicated that best desorption

performance was obtained with ethyl acetate. Thus, ethyl acetate was selected to be optimal

desorption solvent for extraction of OPPs [(Fig 1(e)].

After selecting ethyl acetate as desorption solvent, the effect of desorption solvent volume

was also evaluated for the higher recovery of OPPs. The smaller volumes (100, 200, 2×100,



300, 150×2 µL) of methanol were tried and it was observed that all the analytes could be

effectively desorbed by 2×100 µL of ethyl acetate. Subsequently, 2×100 µL of ethyl acetate

was used for desorption of OPPs from the sorbent [Fig. 1(f)]. Further, the effect of desorption

time was also studied in the range (2, 4, 6, 8, 10 and 12 min). It was found that 8 min was

sufficient for desorption of the analytes completely and longer duration led to a loss of

analytes. Therefore, the succeeding studies were performed at 8 min desorption time for the

highest desorption [Supporting Fig S1]

3.1.6 Reusability and reproducibility of sol-gel FPSE media

The reusability of the FPSE media was investigated by washing the media twice with ethyl

acetate followed by water. The media was then reused for the next analysis run. Under the

optimal conditions, the pesticide sample fortified at 10 ng/g was tested for extraction

efficiency of the media according to the procedure described above. The obtained results

demonstrate that FPSE medium could be reused at least 30 times by <5% loss in the

extraction efficiency. The long-term reusability is due to the stability of the sol-gel FPSE

media formed by strong chemical bonding between cellulose fabric and coated material.

3.2 Method validation

3.2.1 Limit of detection, quantification and method precision

All the OPPs were identified by their retention time and fragmentation spectra in the

chromatograms. Under the optimal experimental conditions, a series of experiments were

performed in triplicate for obtaining linear ranges and precision. The calibration curves were

constructed by plotting the mean peak areas measured versus the concentrations of analytes.

The correlation coefficients (r2) ranging from 0.9982 to 0.9996 are obtained for all the

analytes. The instrumental limits of detection (LODs) (S/N=3) and quantification (LOQs)



(S/N=10) are listed in Table 2. The LODs and LOQs are in the range of 0.033–0.136 ng/g and

0.108–0.448 ng/g for all analytes, respectively. The repeatability of the method (inter-day

precision) was evaluated by determining the analytes five times in the same day and the

intermediate precision (inter-day precision) was obtained by performing the same analysis in

five consecutive days. All the RSD values (Table 2) of intra-day and interday were lower

than 5.0% for the target analytes. It is evident from the low RSD values the developed

FPSE/GC-MS method is reliable as well as reproducible. The obtained results demonstrate

the sensitivity of this method [Table 2] and the clean chromatogram reflects the selectivity of

FPSE [Fig. 2] for the detection of OPPs in complex matrices.

3.2.2 Accuracy

The accuracy (% recovery) of the FPSE/GC-MS method was evaluated for each

organophosphorus pesticide by analysing impregnated tomato, cabbage, brinjal and bean

samples at three different concentrations (10, 50, 250 ng/mL) in triplicate at each

concentration level, followed by FPSE/GC-MS analysis and quantifying them using the

matrix-matched calibration curve. Recovery values of different OPPs in tomato ranged from

92.4% to 98.9%, in cabbage from 88.6% to 97.9%, in brinjal from 88.9% to 95.6% and in

beans from 91.8% to 93.3% [Table 3]. The % recovery values were narrowly dispersed,

suggesting high repeatability of the new method.

3.3 Application to real samples

The optimized and validated method was applied for the evaluation of OPPs in various

vegetable samples [Fig. 3]. To verify the reliability and robustness of the proposed method,

real sample analysis of 20 vegetable samples were conducted. The results obtained

demonstrate that malathion and chlorpyrifos are detected in most of the samples while other



pesticides were not detected or were not quantified as they fall below limits of quantification.

To evaluate the recoveries, comparison of the analytes peak areas in spiked samples with

those obtained for fortified ultrapure water at the same levels gave relative recoveries

between 88.23 % and 98.90 % [Table 3].

3.4 Performance comparison with other contemporary methods

The analytical characteristics of the proposed FPSE method coupled with GC-MS for the

determination of OPPs in vegetable samples were compared with other previously published

methods. Table 4 shows the comparison of the proposed FPSE/GC-MS method with other

extraction methods for OPPs. The presented FPSE/GC-MS method using sol-gel CW 20M

coated FPSE media provides the highest efficiency of extraction with the smallest sample

volume analysis and in the shortest time (over 84% extraction efficiency, 200 μL of sample

volume and 8 min) compared to previous reported methods for extraction of OPPS.

Moreover, most methods require multiple sample preparation prior to extraction while FPSE

is performed in single step. The FPSE media is versatile and reusable which can be used for

thirty consecutive extractions. Hence, FPSE/GC-MS is rapid potential procedure to analyze

OPPs with high extraction yields with reduced sample volume.

4 CONCLUDING REMARKS

The inherent properties such as easy preparation, longer lifetime, regeneration capability,

stability and low cost fit FPSE best among the miniaturized sample preparation techniques.

This presented method for the determination of OPPs in vegetable samples using sol-gel

Carbowax 20M FPSE coupled with GC-MS has been fully optimized and validated. The

relative low detection limits with good linearity, satisfactory recovery and repeatability

demonstrate the selectivity and sensitivity of the method for real sample analysis. Finally, the



applicability of the proposed method was studied in real samples of vegetable (beans, brinjal,

cabbage and tomato). Results of the validation study prove the method to be efficient and

environmentally friendly with a great reduction in time for the screening of OPPs in

vegetables and other food products to estimate potential human exposure.

ACKNOWLEGEMENT

Authors wish to thank University Grant Commission (UGC), New Delhi for supporting this

study through grant.

CONFLICT OF INTEREST

The authors report no conflict of interest.

REFERENCES

1. Wu L., Song Y., Hu M., Xu X., Zhang H., Yu A., Wang Z., Integrated microwave

processing system for the extraction of organophosphorus pesticides in fresh

vegetables. Talanta. 2015, 134, 366–372.

2. Taghani A., Goudarzi N., Bagherian G., Chamjangali, M. A., Application of

nanoperlite as a new natural sorbent in preconcentration of three organophosphorus

pesticides by microextraction in packed syringe coupled with GC – MS. J. Sep. Sci.

2018, 2245-2252.

3. Chen J., Duan C., & Guan Y., Sorptive extraction techniques in sample preparation

for organophosphorus pesticides in complex matrices. J. Chromatogr. B. Analyt.

Technol. Biomed. Life Sci.2010, 878, 1216–1225.



4. Sankararamakrishnan N., Kumar Sharma A., Sanghi, R., Organochlorine and

organophosphorous pesticide residues in ground water and surface waters of Kanpur,

Uttar Pradesh, India. Environ. Int.. 2015, 31, 113–120.

5. Russo M. V., Avino P., Cinelli G., Notardonato I., Sampling of organophosphorus

pesticides at trace levels in the atmosphere using XAD-2 adsorbent and analysis by

gas chromatography coupled with nitrogen-phosphorus and ion-trap mass

spectrometry detectors. Anal. Bioanal. Chem.. 2012, 404, 1517–1527.

6. Haginaka J., Tabo H., Matsunaga H., Preparation of molecularly imprinted polymers

for organophosphates and their application to the recognition of organophosphorus

compounds and phosphopeptides. Anal. Chim. Acta.. 2012, 748, 1–8.

7. Constantine C. A., Mello S. V., Dupont A., Cao X., Santos D., Oliveira O. N.,

Leblanc R. M., Layer-by-layer self-assembled chitosan/poly(thiophene-3-acetic acid)

and organophosphorus hydrolase multilayers. J. Amer. Chem. Soc.. 2003, 125, 1805–

1809.

8. Sapahin, H. A., Makahleh, A., & Saad, B. Determination of organophosphorus

pesticide residues in vegetables using solid phase micro-extraction coupled with gas

chromatography-flame photometric detector. Arab. J. Chem.2014, 1–11.

9. Koureas M., Tsakalof A., Tsatsakis A., Hadjichristodoulou C., Systematic review of

biomonitoring studies to determine the association between exposure to

organophosphorus and pyrethroid insecticides and human health outcomes. Toxicol.

Lett. 2012, 210, 155–168.



10. Jiang L., Huang T., Feng S., Wang J., Zirconium(IV) functionalized magnetic

nanocomposites for extraction of organophosphorus pesticides from environmental

water samples. J. Chromatogr. A. 2016, 1456, 49–57.

11. Han Q., Wang Z., Xia J., Zhang X., Wang H., Ding M., Application of graphene for

the SPE clean-up of organophosphorus pesticides residues from apple juices. J. Sep.

Sci. 2014, 37, 99–105.

12. Jin S., Xu Z., Chen J., Liang X., Wu Y., Qian, X., Determination of organophosphate

and carbamate pesticides based on enzyme inhibition using a pH-sensitive

fluorescence probe. Anal. Chim. Acta., 2004, 523, 117–123.

13. Korrani Z. S., Aini W., Ibrahim W., Nodeh H. R., Aboul-enein H. Y., Separation.

2016, 39, 1144-1151.

14. Wu L., Song Y., Hu M., Zhang H., Yu A., Yu C., Wang Z. Application of magnetic

solvent bar liquid-phase microextraction for determination of organophosphorus

pesticides in fruit juice samples by gas chromatography mass spectrometry. Food

Chem. 2015, 176, 197–204.

15. Maddah B., Alidadi S., Hasanzadeh M., Extraction of organophosphorus pesticides by

carbon-coated Fe3O4 nanoparticles through response surface experimental design. J.

Sep. Sci. 2016, 39, 256-263.

16. Malek, S. K., Nodeh, H. R., & Akbari-adergani, B., Silica-based magnetic hybrid

nano-composite for the extraction and preconcentration of some organophosphorus

pesticides before gas chromatography. J. Sep. Sci. 2018, DOI:

10.1002/jssc.201800090.



17. Nedaei M., Salehpour A., Mozaffari S., Yousefi S. M., Determination of

organophosphorus pesticides by gas chromatography with mass spectrometry using a

large-volume-injection technique after magnetic extraction. J. Sep. Sci. 2014, 37,

2372-2379.

18. Ho Y. M., Tsoi Y. K., Leung K. S. Y., Highly sensitive and selective

organophosphate screening in twelve commodities of fruits, vegetables and herbal

medicines by dispersive liquid-liquid microextraction. Anal. Chim. Acta. 2013, 775,

58–66.

19. Bagheri H., Ayazi Z., Babanezhad E., A sol-gel-based amino functionalized fiber for

immersed solid-phase microextraction of organophosphorus pesticides from

environmental samples. Microchem. J. 2010, 94, 1–6.

20. Wu L., Hu M., Li Z., Song Y., Zhang H., Yu A.,Wang Z., Dynamic microwave-

assisted extraction online coupled with single drop microextraction of

organophosphorus pesticides in tea samples. J. Chromatogr. A. 2015 1407, 42–51.

21. You X., Xing Z., Liu F., Jiang N., Air-assisted liquid-liquid microextraction used for

the rapid determination of organophosphorus pesticides in juice samples. J.

Chromatogr. A. 2013, 1311, 41–47.

22. Zhao, W. J., Sun, X. K., Deng, X. N., Huang, L., Yang, M. M., Zhou, Z. M., Cloud

point extraction coupled with ultrasonic-assisted back-extraction for the determination

of organophosphorus pesticides in concentrated fruit juice by gas chromatography

with flame photometric detection. Food Chem. 2011, 127, 683–688.



23. He J., Song L., Chen S., Li Y., Wei H., Zhao D., Zhang S., Novel restricted access

materials combined to molecularly imprinted polymers for selective solid-phase

extraction of organophosphorus pesticides from honey. Food Chem. 2015, 187, 331–

337.

24. Pinheiro A. de S., da Rocha G. O., De Andrade, J. B., A SDME/GC-MS methodology

for determination of organophosphate and pyrethroid pesticides in water. Microchem.

J. 2011, 99, 303–308.

25. Hu C., He M., Chen B., Hu B., A sol-gel polydimethylsiloxane/polythiophene coated

stir bar sorptive extraction combined with gas chromatography-flame photometric

detection for the determination of organophosphorus pesticides in environmental


26. Kabir A., Mesa R., Jurmain J., Furton K..,Fabric Phase Sorptive Extraction Explained.

Separations. 2017, 4, 21.

27. Santana-Viera S., Guedes-Alonso R., Sosa-Ferrera Z., Santana-Rodríguez, J. J., Kabir

A., Furton K. G., Optimization and application of fabric phase sorptive extraction

coupled to ultra-high performance liquid chromatography tandem mass spectrometry

for the determination of cytostatic drug residues in environmental waters. J.

Chromatogr. A. 2017, 1529, 39–49.

28. Samanidou V., Michaelidou K., Kabir A., Furton, K. G. Fabric phase sorptive

extraction of selected penicillin antibiotic residues from intact milk followed by high

performance liquid chromatography with diode array detection. Food Chem. 2017,

224, 131–138.



29. Roldán-Pijuán M., Lucena R., Cárdenas S., Valcárcel M., Kabir A., Furton, K. G. Stir

fabric phase sorptive extraction for the determination of triazine herbicides in

environmental waters by liquid chromatography. J. Chromatogr. A. 2015, 1376, 35–

45.

30. Lakade, S. S., Borrull, F., Furton, K. G., Kabir, A., Fontanals, N., & Marcé, R. M.

Comparative study of different fabric phase sorptive extraction sorbents to determine

emerging contaminants from environmental water using liquid chromatography-

tandem mass spectrometry. Talanta. 2015, 144, 1342–1351.

31. Samanidou V., Michaelidou K., Kabir A., Furton, K. G., Fabric phase sorptive

extraction of selected penicillin antibiotic residues from intact milk followed by high

performance liquid chromatography with diode array detection. Food Chem. 2017,

224, 131–138.

32. Anthemidis A., Kazantzi V., Samanidou V., Kabir A., Furton K. G., An automated

flow injection system for metal determination by flame atomic absorption

spectrometry involving on-line fabric disk sorptive extraction technique. Talanta.

2016, 156–157, 64–70.

33. Kumar R., Gaurav, Kabir A., Furton K. G., Malik, A. K., Development of a fabric

phase sorptive extraction with high-performance liquid chromatography and

ultraviolet detection method for the analysis of alkyl phenols in environmental

samples. J. Sep. Sci. 2015, 38, 3228–3238.

34. Montesdeoca-Esponda S., Sosa-Ferrera Z., Kabir A., Furton K. G., Santana-

Rodríguez J. J., Fabric phase sorptive extraction followed by UHPLC-MS/MS for the



analysis of benzotriazole UV stabilizers in sewage samples. Anal. Bioanal. Chem..

2015, 407, 8137–8150.

35. Mahpishanian S., Sereshti H., Baghdadi M., Superparamagnetic core-shells anchored

onto graphene oxide grafted with phenylethyl amine as a nano-adsorbent for

extraction and enrichment of organophosphorus pesticides from fruit, vegetable and


Table 1. Physiochemical properties, retention time and ions selected for analysis of OPPs

Analyte Acronym CAS

No.

Molecular

weight

(g/mol)

Log

Kow

Retention

time (min)

Qualitative

ion

Quantitative

ion

Terbufos TER 13071-

79-9

288.42 4.48 6.51 57, 97, 231 57

Malathion MAL 121-

75-5

330.35 2.35 7.77 93, 127, 173 93

Chlorpyrifos CHL 2921-

88-2

350.59 4.70 7.94 97, 197, 314 97

Triazofos TRI 24017-

47-8

313.31 3.55 10.43 77, 134, 161 161



Table 2. Analytical figures of merit obtained from FPSE/GC-MS method

OPPs Linear

range

(ng/g)

Coefficient

of

determination

r2

LOD

(ng/g)

LOQ

(ng/g)

RSD (%)

Intra-day Inter-day

Terbufos 0.5-500 0.9993 0.033 0.108 1.5 2.7

Malathion 0.5-500 0.9989 0.136 0.448 2.6 4.7

Chlorpyrifos 0.5-500 0.9992 0.088 0.290 1.8 2.2

Triazofos 0.5-500 0.9995 0.121 0.399 2.4 3.7

Table 3. Analytical data obtained by proposed method for the determination of OPPs in

vegetable samples.

Sample Nominal

(ng/g)

Amount of TER

found

Amount of MAL

found

Amount of CHL

found

Amount of TRI

found

(ng/g) % %

RSD

(ng/g) % %

RSD

(ng/g) % %

RSD

(ng/g) % %

RSD

Tomato 0 _ _ _ _ _ _ 0.82 _ _ _ _ _

10 9.44 94.4 3.8 9.23 92.4 4.1 9.58 95.8 4.3 9.37 93.7 3.6

50 49.43 98.9 3.6 47.790 95.6 3.5 49.45 98.9 4.8 48.11 96.2 3.7

250 246.67 98.7 4.1 239.40 95.7 3.8 245.60 98.2 2.8 239.60 95.8 4.1

Cabbage 0 _ _ _ 0.64 _ _ _ _ _ _ _ _

10 8.86 88.6 3.9 9.01 90.1 3.9 9.35 93.5 4.1 9.24 92.4 3.5

50 45.01 90.0 3.7 46.50 93.0 4.1 48.95 97.9 4.6 47.12 94.2 3.4

250 232.56 93.0 4.2 238.23 95.3 4.3 244.56 97.8 3.5 238.24 95.2 4.2

Brinjal 0 _ _ _ _ 0.56 _ _ _ _ _



10 8.91 89.1 3.2 9.24 92.4 3.5 9.21 92.1 3.9 8.89 88.9 3.5

50 45.28 90.5 2.8 46.66 93.3 2.9 47.81 95.6 4.1 45.84 91.6 3.3

250 233.63 93.4 2.5 228.35 91.3 2.7 236.68 94.6 3.2 231.95 92.7 2.6

Beans 0 _ _ _ 0.78 _ _ 0.45 _ _ _ _ _

10 9.73 97.3 3.5 9.37 93.7 4.5 9.14 91.4 3.4 9.51 95.1 3.7

50 48.34 96.6 2.9 47.42 94.8 4.1 44.11 88.2 4.4 46.66 93.3 2.6

250 236.13 94.4 3.1 235.80 94.3 3.6 229.50 91.8 3.1 240.10 96.0 3.9

Table 4. Comparison of performance characteristics of the proposed method with reported

methods.

S.No. Analyte Matrix Extraction

method

Detection Linearity

ng/g

LOD

(ng/g)

RSD

%

Reference

1 Phorate,

diazinon,

methyl

parathion,

fenitrothion,

fenthion,

fenaniphos

vegetables MASE GC-MS 0.5-50 0.093-

0.26

<11.6 [1]

2 Fenitrothion,

chlorpyrifos,

fenthion,

methidathion

Environmental

water samples

Zr (IV)

nanocmposites

GC-MS 100-

20000

0.10-

10.30

<10.42 [10]

3 Ethoprophos,

phorate,

terbufos,

dimethoate,

malathion,

fenamiphos

honey RAM-MIP-SPE GC-FPD 10-1000 0.5-1.9 <4.81 [23]

4 Dimethoate,

methyl

parathion,

ethion,

permethrin

Environmental

water samples

SDME GC-MS 0.15-60 0.05-

0.38

<14.35 [24]

5 Terbufos,

malathion,

chlorpyrifos,

triazophos

vegetables FPSE GC-MS 0.5-500 0.033-

0.136

<4.8 This work

MASE: Microwave accelerated solvent elution

RAM-MIP-SPE: Restricted access materials- molecularly imprinted polymers- solid-phase extraction

SDME: Single drop Microextraction



FIGURE CAPTIONS

Figure 1. Effect of (a) stirring speed; (b) extraction time; (c) sample pH; (d) salt addition; (e)

desorption solvent type; (f) desorption solvent volume; (g) desorption time on the extraction

efficiency of the analytes [ sample volume: 10 mL; concentration of the analytes 5 ng/mL]

Figure 2. FPSE/GC-MS chromatogram of a standard solution containing 0.5 ng/mL of OPPs

[Extraction time: 25 min; stirring speed: 1200 rpm; desorption solvent: ethyl acetate;

desorption solvent volume: 2×100 μL; desorption time: 10 min; pH: 6].



Figure 3. FPSE/GC-MS chromatograms of OPPs in real sample (a) blank tomato (b) spiked

tomato.

Date post:	13-May-2020
Category:	Documents
Upload:	others
View:	3 times
Download:	0 times

Application of fabric phase sorptive extraction/gas...

Documents