Ye et al. (2014) extracted seven phthalates from water samples by using magnetic
graphene solid-phase extraction. They used ethyl acetate to desorb ultrasonically the
analytes. The eluted solution was applied to gas chromatography–mass spectrometric
analysis. The method had recovery rates of 88–110%, and the limits of detection were
0.01–0.056 μg/L, with the relative standard deviations less than 8.5%. Zhao et al.
(2016) prepared Fe 3 O 4 @PPy magnetic nanoparticles as sorbents for the
preconcentration of 16 phthalates in tap and lake water. They analyzed the phthalates
by gas chromatography coupled with tandem mass spectrometry and obtained recovery
rates of 80.4–108.2%, with the limits of detection of 0.006–0.021 μg/L, and the relative
standard deviations were less than 12.8%. Luo et al. (2012) prepared magnetic carbon
nanotubes and used it for the extraction of 16 phthalates from tap water samples. A
small amount, i.e. 0.10 mL, of magnetic carbon nanotubes suspension was added into
10 mL sample solution and vortex agitated for 3 min. Then an external magnet was
applied to gather magnetic adsorbent, and the phthalates were eluted with 1.00 mL
acetone which was collected and evaporated to dryness at 35
C under nitrogen flow
followed by redissolving in 0.10 mL acetone for the subsequent gas chromatography–
mass spectrometric analysis. The limits of detection of the method were
0.0049–0.038 μg/L, and the recovery rates were 64.6–125.6%, with the relative
standard deviations less than 11.7% (intra-day) and 14.6% (inter-day). Wang et al.
(2015a) used magnetic graphite carbon nitride nanocomposites for the determination of
four phthalates in water samples by high-performance liquid chromatography. The
detection limits of the method were 0.05 Æ 0.1 μg/L, and the recoveries were in the
range of 79.4–99.4%. Wu et al. (2012) used graphene-based magnetic nanoparticles as
adsorbents for the analysis of five phthalates in water and beverage by highperformance liquid chromatography. The detection limits of the method were
0.01–0.04 μg/L, and the enrichment factors were 1574–2880. Liu et al. (2015a) used
magnetic nanoporous carbon to adsorb phthalates in lake water and juice samples, and
the detection limits of three phthalates in water samples were 0.10 μg/L, with the
relative standard deviations of 4.2–7.0%. The magnetic zeolite imidazolate framework8 has been applied to the extraction of five phthalates in environmental water and
separation and detection by high-performance liquid chromatography. The detection
limits were 0.08–0.24 μg/L, and the relative standard deviations were less than 5.5%,
with the recoveries of 85.6–103.6% (Liu et al. 2015b). The magnetic molecularly
imprinted polymer nanoparticles combined with gas chromatography–tandem mass
spectrometry has been reported to detect di(2-ethylhexyl) phthalate in water samples.
The method has a detection limit of 0.02 μg/L. The recoveries were 93.3–103.2%, and
the relative standard deviations were 1.2–3.2% (Li et al. 2016).
15.3 The Separation and Detection Methods for Phthalates
in Water
The commonly used separation and detection methods for phthalates in water
samples are gas chromatography with flame ionization detection or mass spectrometric detection and high-performance liquid chromatography with ultraviolet
15 Analytical Methods for Phthalates in Water Samples
555
graphene solid-phase extraction. They used ethyl acetate to desorb ultrasonically the
analytes. The eluted solution was applied to gas chromatography–mass spectrometric
analysis. The method had recovery rates of 88–110%, and the limits of detection were
0.01–0.056 μg/L, with the relative standard deviations less than 8.5%. Zhao et al.
(2016) prepared Fe 3 O 4 @PPy magnetic nanoparticles as sorbents for the
preconcentration of 16 phthalates in tap and lake water. They analyzed the phthalates
by gas chromatography coupled with tandem mass spectrometry and obtained recovery
rates of 80.4–108.2%, with the limits of detection of 0.006–0.021 μg/L, and the relative
standard deviations were less than 12.8%. Luo et al. (2012) prepared magnetic carbon
nanotubes and used it for the extraction of 16 phthalates from tap water samples. A
small amount, i.e. 0.10 mL, of magnetic carbon nanotubes suspension was added into
10 mL sample solution and vortex agitated for 3 min. Then an external magnet was
applied to gather magnetic adsorbent, and the phthalates were eluted with 1.00 mL
acetone which was collected and evaporated to dryness at 35
C under nitrogen flow
followed by redissolving in 0.10 mL acetone for the subsequent gas chromatography–
mass spectrometric analysis. The limits of detection of the method were
0.0049–0.038 μg/L, and the recovery rates were 64.6–125.6%, with the relative
standard deviations less than 11.7% (intra-day) and 14.6% (inter-day). Wang et al.
(2015a) used magnetic graphite carbon nitride nanocomposites for the determination of
four phthalates in water samples by high-performance liquid chromatography. The
detection limits of the method were 0.05 Æ 0.1 μg/L, and the recoveries were in the
range of 79.4–99.4%. Wu et al. (2012) used graphene-based magnetic nanoparticles as
adsorbents for the analysis of five phthalates in water and beverage by highperformance liquid chromatography. The detection limits of the method were
0.01–0.04 μg/L, and the enrichment factors were 1574–2880. Liu et al. (2015a) used
magnetic nanoporous carbon to adsorb phthalates in lake water and juice samples, and
the detection limits of three phthalates in water samples were 0.10 μg/L, with the
relative standard deviations of 4.2–7.0%. The magnetic zeolite imidazolate framework8 has been applied to the extraction of five phthalates in environmental water and
separation and detection by high-performance liquid chromatography. The detection
limits were 0.08–0.24 μg/L, and the relative standard deviations were less than 5.5%,
with the recoveries of 85.6–103.6% (Liu et al. 2015b). The magnetic molecularly
imprinted polymer nanoparticles combined with gas chromatography–tandem mass
spectrometry has been reported to detect di(2-ethylhexyl) phthalate in water samples.
The method has a detection limit of 0.02 μg/L. The recoveries were 93.3–103.2%, and
the relative standard deviations were 1.2–3.2% (Li et al. 2016).
15.3 The Separation and Detection Methods for Phthalates
in Water
The commonly used separation and detection methods for phthalates in water
samples are gas chromatography with flame ionization detection or mass spectrometric detection and high-performance liquid chromatography with ultraviolet
15 Analytical Methods for Phthalates in Water Samples
555