Journal of Geoscience and Environment Protection
2013. Vol.1, No.2, 13-17
Published Online October 201 3 in SciRes (http://www.scirp.org/journal/gep) http://dx.doi.org/10.4236/gep.2013.12003
Copyright © 2013 SciRes.
Determination of Triclocarban, Triclosan and Methyl-Triclosan in
Environmental Water by Silicon Dioxide/Polystyrene Composite
Microspheres Solid-Phase Extraction Combined with
Yinan Wang1,2, Pengfei Li1,3, Yan Liu1, Bing Chen1, Jinyu Li1, Xikui Wang1*
1School of Chemical Engineering, Shandong Polytechnic University, Jinan, China
2School of Biological Science and Technology, Beijing Forestry University, Beijing, China
3Jinan Water Group Company Limited, J inan, China
Received July 2013
This paper developed a sensitive and efficient analytical method for triclocarban (TCC), triclosan (TCS)
and Methyl-triclosan (MTCS) determination in environmental water, which involves enrichment by using
silicon dioxide/polystyrene composite microspheres solid-phase extraction and detection with HPLC-
ESI-MS. The influence of several operational parameters, including the eluant and its volume, the flow
rate and acidity of water sample were investigated and optimized. Under the optimum conditions, the lim-
its of detection were 1.0 ng/L, 2.5 and 4.5 ng/L for TCC, TCS, and MTCS, respectively. The linearity of
the method was observed in the range of 5 - 2000 ng/L, with correlation coefficients (r2) > .99. The spiked
recoveries of TCC, TCS and MTCS in water samples were achieved in the range of 89.5% - 96.8% with
RSD below 5.7%. The proposed method has been successfully applied to analyze real water samples and
satisfactory results were achieved.
Keywords: Triclocarban; Triclosan; Solid-Phase Extraction; Silicon Dioxide/Polystyrene Composite
Over the past decades, increasing residues of pharmaceuti-
cals and personal care products (PPCPs) have been detected in
the aquatic environment. Hundreds of tones of these com-
pounds are dispensed in communities every year. The conti-
nuous input of such compounds may affect water quality and
potentially affect the ecosystem and human health (Halden &
Paull, 2005; Ahn et al., 2008; Chalew & Halden, 2009). Tric-
locarban (N-(4-chlorophenyl)-N-(3,4-dichlorophenylurea, TCC)
and triclosan (5-chloro -2-(2, 4-dichloro-phenoxy)-phenol, TCS)
are both antimicrobials that are added to a wide range of
household and personal-care products, such as shampoos, soaps,
creams, mouthwash and toothpaste. However, TCC has harmful
effects on humans and other animals because it increases me-
themoglobinemia (Ponte et al., 1974). TCC exposure enhances
the estradiol-dependent or testos-terone-dependent activation of
the estrogen receptor-responsive and the androgen receptor-
responsive gene expression in human ovary cells (Ahn et al.,
2008). Moreover, TCC affects the transcription of genes that
respond to the thyroid hormone in frog and rat cells (Hinther et
al., 2011). Bioaccumulation studies have shown that TCC ac-
cumulates in algae (Coogan et al., 2007) and snails (Coogan et
al., 2008). Similarly, TCS was found to be acutely toxic to a
number of aquatic organisms, particularly for algae species, and
was recently shown to the modulate thyroid function of amphi-
bians at concentrations as low as .15 μg/L (Orvos et al., 2002).
In addition, triclosan has been shown to phototransform into
chlorinated dibenzodioxins (Mezcua et al., 2004). Methyl-tric-
losan (MTCS) is a metabolite of TCS. It is more lipophilic and
environmentally persistent (Chu & Metcalfe, 2007; Coogan et
al., 2007), suggesting its relatively high bioaccu-mulation po-
tential in aquatic organisms (Coogan et al., 2007).
The potential risk to the environment and human health gen-
erated by TCC, TCS and MTCS is currently drawing consider-
able attention worldwide. Therefore, it is very essential to es-
tablish simple, sensitive and reliable analytical method to de-
termine these compounds in various environmental water sam-
ples for safety evaluation.
Generally, a sample enrichment and clean-up procedure are
often needed prior to the instrumental determination because
these pollutants are present at very low levels in environmental
water samples (μg/L or less). Many sample pretreatment me-
thods, such as liquid-liquid extraction (LLE) (Canosa et al.,
2007; Sun et al., 2012), dispersive liquid-liquid microextraction
(DLLME) (Guo et al., 2009; Zhao et al., 2011), solid-phase ex-
traction (SPE) (Halden & Paull, 2004; Sapkota et al., 2007),
solid-phase micro-extraction (SPME) (Montes et al., 2005),
hollow fiber assisted liquid-phase microextraction (HF-LPME)
(Zhao et al., 2007), and stir bar sorptive extraction (SBSE) (Ka-
waguchi et al., 2008) have been used for the enrichment of TCS
Traditional LLE is widely used as a sample preparation tech-
nique by several authors (Liska et al., 1989), but it is tedious,
time consuming, costly and needs large volumes toxic and
Y. N. WANG ET AL.
Copyright © 2013 SciRes.
flammable solvents. SPME has drawbacks of high cost, sample
carry-over, and a decline in performance with time. LPME
produces some obvious disadvantages: solvent drops are ready
to break, air bubble is tending to form, time is long and some-
times equilibrium is not achieved easily in short time (Melwan-
ki & Fuh, 2008).
SPE has extinguished from many extraction techniques and
has been widely used for the concentration and measurement of
many pollutants (Halden & Paull, 2004; Chu & Metc alfe, 2007;
Sapkota et al., 2007). SPE has been an effective sample-hand-
ing technique with many obvious advantages such as high re-
covery, high pre-concentration factors, low consumption of or-
ganic solvents, simplicity, easy operation and automation. In
SPE the analytes to be extracted are partitioned between a solid
and liquid and these analytes must have a greater affinity for
the solid phase than for the same matrix, which are better than
the two immiscible liquids as in LLE. The different mechan-
isms of retention or elution are due to inter-molecular forces
between the analytes, the active sites on the surface of the ad-
sorbent and liquid phase or matrix. Therefore, the types of the
adsorbents are the key to SPE process.
The silicon dioxide/polystyrene composite microspheres (SiO2/
PS) is a mixed-mode sorbent which was prepared through po-
lymerization of styrene on the surface of SiO2. It has both a
hydrophilicity of SiO2 and a lipophilicity of polystyrene, and
was successfully used to extract nitrophenol and alkylphenol
from aqueous environmental samples (Shen S. C. et al., 2012).
Sensitive and selective approaches for determination of TCC,
TCS and MTCS have been established, including GC/MS (Coo-
gan et al., 2007; Kawaguchi et al., 2008)], GC/MS/MS (Boeh-
mer et al., 2004), LC/MS (Chu & Metcalfe, 2007; Sapkota et al.,
2007) and LC/MS/MS (Zhao et al., 2011; Shen J. et al., 2012).
In order to reduce complex derivatization step and possible in-
terferences of other compounds, HPLC-ESI-MS was selected
for the sensitive determination of TCC, TCS and MTCS be-
cause they are compounds with strong polarity.
The aim of this work is to develop a rapid SPE-UHPLC-MS
method for simultaneous dete rmination of T CC, T CS and MTCS
in environmental water samples. To accomplish its application
in environmental monitoring of environmental water, silicon
dioxide/polystyrene (SiO2/PS) SPE cartridges was selected for
the pre-concentrations. A series of key parameters influencing
the enrichment efficiency of TCC, TCS and MTCS have been
investigated and optimized. It could provide enough valid evi-
dence for post-study .
Materials and Methods
HPLC-grade methanol, acetonitrile, and acetone were pur-
chased from Tedia Company Inc. (Fairfield, Ohio, USA). TCC
were purchased from Dajie Technical Co. Ltd. (Hunan, China).
TCS and MTCS were obtained from Dr. Ehrenstorfer (Augs-
burg, Germany). Standard stock solution of TCC, TCS and
MTCS (100 mg∙L) was prepared in methanol and then stored at
4˚C. Fresh working solutions were prepared daily by diluting
the stock solution with purified water. The SiO2/PS sorbent (5
μm) was obtained from Lantian Pharmaceutical co. Ltd. (Wu-
A SiO2/PS packed cartridge was prepared by modifying an
Agilent cleanert ODS C18 cartridge (70 mm × 14 mm, 6 mL,
polypropylene), which was purchased from Agilent Techno-
logies (Palo Alto, CA,USA). 500 mg of SiO2/PS sorbent was
packed into the cartridge, after the C18 packing was evacuated.
The polypropylene upper frit and lower frit were placed at each
end of the cartridge to hold the SiO2/PS packing fixed. Then the
bottom end of the cartridge was connected to a SHBIII vacuum
pump (Great Wall Scientific and Trade Co. Ltd., Zhengzhou,
Henan), and the upper end of cartridge was connected with a
PTFE suction tube, the other end of which was immersed into
the water sample. The whole SPE device was washed by suffi-
cient methanol and purified water before the first usage, in
order to avoid the pollution of organic contaminants.
The high-performance liquid chromatography-mass spectro-
metry equipment was an Agilent 1100 LC system, including an
electrospray ionization mass spectrometer (ESI-MS), a quater-
nary pump, a column thermostat, and an automatic sample in-
jector with a 100 μL loop. A personal computer equipped with
the Agilent ChemStation program for HPLC-MS was used to
process the chromatographic data. An Agilent Eclipse XDB-C8
column, 4.6 mm × 150 mm, 5 μm particle size, was used to
held at 30˚C to analyze TCS. The injected sample volume was
10 μL, and the binary mobile phase was composed of 25%
water and 75% methanol (v/v) at a constant flow rate of .8
mL/min. Under these chromatographic conditions, one HPLC-
MS run can be finished within 10 min. MS conditions were
maintained as follows: drying gas 10.0 L/min; nebulizer pres-
sure 30 psi; chemcur. .32 μA; quadratic temperature 99˚C; high
vac. 1.1 × 10−5 Torr. Target compounds analysis was carried
out in negative ionization mode and quantification was per-
formed under SIM conditions.
SPE Proc edu re
The cartridge packed with SiO2/PS adsorbent was condition-
ed with 10 mL of methanol in acetone (50%), followed by 5
mL of methanol and 5 mL of water before use. Aliquots (300
mL) of water sample were passed through the cartridges at a
flow rate of approximately 10 mL/min. Following the loading
of the sample, the cartridge was eluted with 5 mL hexane, and 5
mL dichloromethane to remove the co-adsorbed matrix sub-
stance. After the cartridge was dried with a vacuum, 2 × 5 mL
of 5% methanol in water was used to wash it. Then the car-
tridge was dried under vacuum for 10 min. The cartridge was
eluted with 3 × 5 mL methanol in acetone (50%) at a slow rate
of 1 mL/min. The combined extract was dried under N2 gas a nd
then reconstituted in .5 mL of methanol.
Results and Discussion
Selection of the Adsorbents
SPE has gained popularity as a technique for the extraction
of polar to medium-polarity analytes from aqueous environ-
mental samples. With a number of different sorbents applied in
SPE and all kinds of commercial SPE cartridges emerged in the
market, SPE can almost meet all the demands of preconcentra-
tions and clean-up in the environmental monitoring. The reco-
veries of TCC, TCS and MTCS were investigated by using four
different SPE cartridges: Agilent SampliQ Optimised Polymer
technology (OPT), Agela Cleanert PEP, bamboo-activated char-
Y. N. WANG ET AL.
Copyright © 2013 SciRes.
coal (BAC) and SiO2/PS with eluate of 50% methanol in ace-
tone. As shown in Figure 1, the experimental results indicate
that the OPT sorbent is unsuitable for the isolation of TCC,
TCS and MTCS because of its poor recoveries. The Agela
Cleanert PEP and the BAC sorbents showed efficient selective
adsorption for TCC, TCS and MTCS, respectively. However,
these SPE cartridges are unsuitable for the simultaneous deter-
mination of all three analytes. Only the SiO2/PS sorbent showed
satisfactory recoveries for TCC, TCS and MTCS and was thus
selected to be the SPE material in this study.
Selection of the Eluant and Its Volume
Eluant is a key parameter that affects the recovery of target
compounds. Three eluants, including methanol, acetone, and
50% methanol in acetone, were tested. The results indicate that
50% methanol in acetone has better desorption efficiencies (the
recoveries were 91.2%, 94.5% and 96.0% for TCC, TCS and
MTCS, respectively), as shown in Figure 2. Therefore, 50%
methanol in acetone was chosen as the eluant.
Then the effect of eluant volume which directly affects the
recovery of analytes was investigated. A series of experiments
were designed and performed by changing the volumes of elu-
ant over the range of 2.3 - 15.0 mL. The results showed that the
recoveries TCC, TCS and MTCS increased with the increase of
the eluant volume between 3.0 mL and 9.0 mL (Figure 3).
When the volume is more than 9.0 mL, the extraction efficien-
cies of TCC, TCS and MTCS almost kept constant. Therefore,
9.0 mL eluant was used as the eluant in all subsequent experi-
Influence of pH
To examine the effect of the pH of the water sample on the
Effect of adsorbents on the recoveries of TCC, TCS
Effect of eluant on the recoveries of TCC, TCS and
recoveries of TCC, TCS and MTCS, a series of experiments
were performed by changing the pH of the water samples from
2.0 to 13.0, as shown in Figure 4. The result indicates that the
recoveries of TCC, TCS and MTCS maintain high from pH 2 to
pH 10. However, under the condition of alkalinity, the recovery
of TCC kept satisfactory while that of TCS and MTCS dropped
dramatically. This result may possibly be attributed to the struc-
tural characteristics of TCS. Strong alkalinity may result in the
deprotonation of the hydroxyl of TCS and MTCS, which af-
fects their solubility in water. According to these experimental
results, the pH of solutions was adjusted in the range from 4.0
to 6.0 in the subsequent experiments.
Influence of Flow Rate
The flow rate of water sample affects the recovery of TCS
and controls the sample pretreatment time. Here, the flow rates
of the sample were optimized in the range of 1.0 - 3.0 mL /min
with the limitation on the negative pressure of the pump. The
results from Figure 5 show that the flow rate had no obvious
influence on the extraction efficiency of TCC, TCS and MTCS.
In order to save extraction time, the highest flow rate, 3.0
mL/min, was adopted in the following experiments
Under the given optimal conditions, a number of important
parameters of the method, such as linearity range, correlation
coefficient (r2), reproducibility, limit of detection, and recovery,
were studied. Linearity was tested by varying the concentra-
tions of TCC, TCS and MTCS from 5 ng/L to 20,000 ng/L,
Effect of volume of eluant on the recoveries of TCC,
TCS and MTCS.
Effect of pH of samples on the recoveries of TCC,
TCS and MTCS.
2 4 6 810 12 14 16
Volume of eluant
246810 12 14
Recoveri es (%)
Y. N. WANG ET AL.
Copyright © 2013 SciRes.
Effect of flow rate on the recoveries of TCC, TCS
with r2 > .99. Limits of detection (LOD) of the analytes were
calculated with signal/noise ratios (S/N) of 3. Limits of quanti-
fication (LQD) were calculated with signal/noise ratios (S/N) of
10. Detailed information on the limits of the analytes was pro-
vided in Table 1.
To investigate the effects of the sample matrix, two water
samples collected from Xiaoqing River were spiked with TCC,
TCS and MTCS at different levels and were then analyzed. The
recoveries of spiked water are listed in Table 2. The effects of
the matrix on the signal were insignificant after sample clean-
up by using SPE.
Determination of TCC, TCS and MTCS in
Environmental Water Samples
For a preliminary survey and for method validation, the me-
thod developed was used for simultaneous analysis of the three
target compounds in a variety of environmental water samples.
Three river water samples were collected in Xiaoqing Rivers in
Jinan area, Shandong Province, China. The sample 1# was col-
lected in the upstream of the wastewater treatment plant, .5 km
from the discharge port. The sample 2# was collected in the
downstream of wastewater treatment plant near the discharge
port, and samples 3# was collected downstream of wastewater
treatment plant, apart from the discharge port 2 km. Two sea
water samples collected in Yellow Sea at Qingdao port. Sample
1# was from the coast, and sample 2# was 2 km apart from the
coast. Figure 6 shows a typical HPLC-ESI-MS chromatogram
obtained from a river water extract. The average concentrations
of the target compounds in a variety of environmental water
samples are listed i n Table 3.
A procedure for the determination of TCC, TCS and MTCS
in environmental water samples is developed. The analytes
were simultaneously isolated using silicon dioxide/polystyrene
composite microspheres SPE sorbent, and then they were de-
termined with UHPLC-ESI-MS. Under the optimized condi-
tions, the LODs were 1.0 ng/L, 2.5 ng/L and 4.5 ng/L for TCC,
TCS and MTCS, respectively. The spiked recoveries of TCC,
TCS and MTCS in environmental water samples were achieved
in the range of 89.5% - 96.8% with RSD below 5.7%. With this
method, the TCC, TCS and MTCS in a variety of environmen-
tal water samples from Xiaoqing Rivers and Yellow Sea were
detected. This work indicates that the proposed method is con-
Linear range and limits of detection of the method.
Analyte Liner range (ng/L) r2 LOD LOQ
5 - 2000
5 - 2000
5 - 2000
Experimental recoveries of TCC, TCS and MTCS from spiked real
Analyte Found (ng/L) Added (ng/L) Recovery (%) RSD (%)
Note: aNot detecte d.
Typical HPLC-ESI-MS chromatogram obtained
from river water.
Analytical results of TCC, TCS and MTCS in environmental water
sa mp le s .
SAmples TCC (ng/L) TCS (ng/L) MTCS (ng/L)
Xiaoqing Ri ver
Note: aNot detecte d.
venient and reliable for the determination of TCC, TCS and
MTCS in environmental water samples. This method could be
applied to monitor TCC, TCS in various environmental water
The authors are thankful to the financially supports by the
National Natural Science Foundation of China (No. 21077069).
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