9.4.2 Carbon-Based Nanomaterials in Analytic Chemistry
Among the current different uses of these advanced materials, CNTs have also found
in the analytical chemistry field for the determination of persistent organic
compounds in environment (Ma et al. 2010). PAHs are one of the major classes of
persistent organic compounds. Monitoring of these compounds continues to be of
importance as a number of PAHs have high carcinogenicity and mutagenicity (Zhu
et al. 2005). However, problems exit for monitoring of PAHs mainly because of very
low concentrations in environment. Many modern analytical techniques have been
developed and subsequently applied for the analysis of PAHs in the environment
such as high performance liquid chromatography coupled with ultraviolet detector
(HPLC–UV) (Brown and Peake 2003), fluorescence detector (HPLC– -FLD)
(Bourdat-Deschamps et al. 2007; García-Falcíon et al. 2004), and gas chromatography coupled with flame ionization detector (GC–FID) (Zuazagoitia et al. 2009), with
mass spectrometry (GC/MS) (Li et al. 2007; King et al. 2004) and with time-of-flight
mass spectrometry (GC–TOF-MS) (Purcaro et al. 2007). In recent years, there has
been growing interest in development of sensitive and selective method for
analyzing the PAHs in environmental samples and CNTs have been played their
role in this development.
For the determination of PAHs in aqueous solution, Wang et al. developed a
novel method using multi-walled carbon nanotubes (MWCNTs) as a solid-phase
extraction adsorbents combined with high performance liquid chromatography
(HPLC). For the determination of 10 polycyclic aromatic hydrocarbons (i.e., naphthalene, acenaphthylene, fluorene, phenanthrene, anthracene, fluoranthene, pyrene,
ben[a]anthracene, benzo[b]fluoranthene, and benzo[k]fluoranthene) in tap and river
waters, main parameters that affected extraction efficiency including the eluent
volume, sample flow rate, sample pH, and the sample volume were optimized, and
the sensitivity and precision of the method were investigated. Recovery values, RSD
and LODs were in the range 78.7–118.1%, 1.7–4.8% and 5–58 ng/L, respectively.
Ma et al. (2010) developed SPE-GC-MS method using MWCNTs as sorbent and
which enabled selective and sensitive analysis of PAHs at very low levels in
complex water environment and easy identification of the individual compounds.
The optimized method was successfully applied to the determination of 16 PAHs in
real environmental water samples (tap water, river water, and sea water). LOD and
RSD were determined in the range 2.0–8.5 ng/L and 1.2%–12.1%, respectively.
Recovery values of developed method were in the range 76.0–125.5%,
74.5–127.0%, and 70.0–122.0% for real spiked samples from river water, tap
water, and seawater, respectively.
In the search of new advance SPME coating materials lot of efforts have been
paid to nano-scaled materials of different chemistry. Maghsoudi and Noroozian
(2012) used a headspace solid-phase microextraction (SPME) method using a
stainless-steel wire electrophoretically coated with dodecylsulfate modified multiwalled carbon nanotubes for the gas chromatographic (GC) determination of PAHs
in aqueous samples. This CNT based material is stable enough to carry out at least
218
A. Singh et al.
Among the current different uses of these advanced materials, CNTs have also found
in the analytical chemistry field for the determination of persistent organic
compounds in environment (Ma et al. 2010). PAHs are one of the major classes of
persistent organic compounds. Monitoring of these compounds continues to be of
importance as a number of PAHs have high carcinogenicity and mutagenicity (Zhu
et al. 2005). However, problems exit for monitoring of PAHs mainly because of very
low concentrations in environment. Many modern analytical techniques have been
developed and subsequently applied for the analysis of PAHs in the environment
such as high performance liquid chromatography coupled with ultraviolet detector
(HPLC–UV) (Brown and Peake 2003), fluorescence detector (HPLC– -FLD)
(Bourdat-Deschamps et al. 2007; García-Falcíon et al. 2004), and gas chromatography coupled with flame ionization detector (GC–FID) (Zuazagoitia et al. 2009), with
mass spectrometry (GC/MS) (Li et al. 2007; King et al. 2004) and with time-of-flight
mass spectrometry (GC–TOF-MS) (Purcaro et al. 2007). In recent years, there has
been growing interest in development of sensitive and selective method for
analyzing the PAHs in environmental samples and CNTs have been played their
role in this development.
For the determination of PAHs in aqueous solution, Wang et al. developed a
novel method using multi-walled carbon nanotubes (MWCNTs) as a solid-phase
extraction adsorbents combined with high performance liquid chromatography
(HPLC). For the determination of 10 polycyclic aromatic hydrocarbons (i.e., naphthalene, acenaphthylene, fluorene, phenanthrene, anthracene, fluoranthene, pyrene,
ben[a]anthracene, benzo[b]fluoranthene, and benzo[k]fluoranthene) in tap and river
waters, main parameters that affected extraction efficiency including the eluent
volume, sample flow rate, sample pH, and the sample volume were optimized, and
the sensitivity and precision of the method were investigated. Recovery values, RSD
and LODs were in the range 78.7–118.1%, 1.7–4.8% and 5–58 ng/L, respectively.
Ma et al. (2010) developed SPE-GC-MS method using MWCNTs as sorbent and
which enabled selective and sensitive analysis of PAHs at very low levels in
complex water environment and easy identification of the individual compounds.
The optimized method was successfully applied to the determination of 16 PAHs in
real environmental water samples (tap water, river water, and sea water). LOD and
RSD were determined in the range 2.0–8.5 ng/L and 1.2%–12.1%, respectively.
Recovery values of developed method were in the range 76.0–125.5%,
74.5–127.0%, and 70.0–122.0% for real spiked samples from river water, tap
water, and seawater, respectively.
In the search of new advance SPME coating materials lot of efforts have been
paid to nano-scaled materials of different chemistry. Maghsoudi and Noroozian
(2012) used a headspace solid-phase microextraction (SPME) method using a
stainless-steel wire electrophoretically coated with dodecylsulfate modified multiwalled carbon nanotubes for the gas chromatographic (GC) determination of PAHs
in aqueous samples. This CNT based material is stable enough to carry out at least
218
A. Singh et al.