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1.
Single drop microextraction combined with graphite furnace atomic absorption spectrometry for determination of lead in biological samples 总被引:1,自引:0,他引:1
Single drop microextraction combined with graphite furnace atomic absorption spectrometry is introduced for the determination
of trace lead in water samples. A drop of 1-phenyl-3-methyl-4-benzoyl-5-pyrazolone (PMBP) dissolved in benzene was held at
the tip of a microsyringe and immerged into the sample solution which was stirred, the solvent drop interacts with the sample
solution, and the analyte was extracted into the drop and concentrated. After extracting for a period of time, the drop was
retracted into the microsyringe and directly injected into graphite furnace for GFAAS determination of Pb. Several factors
affecting the extraction efficiency, such as pH of sample solution, drop volume, stirring rate and extraction time, were optimized.
Under the optimized conditions, an enhancement factor of 16 was achieved, and the detection limits for Pb were 25 ng L−1. The relative standard deviation for seven replicate determination of 10 ng mL−1 Pb was 6.1%. The method was applied to determine trace Pb in biological samples with satisfactory results.
Correspondence: Pei Liang, Key Laboratory of Pesticide & Chemical Biology of Ministry of Education, College of Chemistry,
Central China Normal University, Wuhan 430079, P.R. China 相似文献
2.
Akhmad Sabarudin Osamu Noguchi Mitsuko Oshima Keiro Higuchi Shoji Motomizu 《Mikrochimica acta》2007,159(3-4):341-348
Chitosan resin functionalized with 3,4-dihydroxy benzoic acid (CCTS-DHBA resin) was used as a packing material for flow injection
(FI) on-line mini-column preconcentration in combination with inductively coupled plasma-atomic emission spectrometry (ICP-AES)
for the determination of trace elements such as silver, bismuth, copper, gallium, indium, molybdenum, nickel, uranium, and
vanadium in environmental waters. A 5-mL aliquot of sample (pH 5.5) was introduced to the minicolumn for the adsorption/preconcentration
of the metal ions, and the collected analytes on the mini-column were eluted with 2 M HNO3, and the eluates was subsequently transported via direct injection to the nebulizer of ICP-AES for quantification. The parameters
affecting on the sensitivity, such as sample pH, sample flow rate, eluent concentration, and eluent flow rate, were carefully
examined. Alkali and alkaline earth metal ions commonly existing in river water and seawater did not affect the analysis of
metals. Under the optimum conditions, the method allowed the determination of metal ions with detection limits of 0.08 ng mL−1 (Ag), 0.9 ng mL−1 (Bi), 0.07 ng mL−1 (Cu), 0.9 ng mL−1 (Ga), 0.9 ng mL−1 (In), 0.08 ng mL−1 (Mo), 0.09 ng mL−1 (Ni), 0.9 ng mL−1 (U), and 0.08 ng mL−1 (V). By using 5 mL of sample solution, the enrichment factor and collection efficiency were 8–12 fold and 96–102%, respectively,
whereas the sample throughput was 7 samples/hour. The method was validated by determining metal ions in certified reference
material of river water (SLRS-4) and nearshore seawater (CASS-4), and its applicability was further demonstrated to river
water and seawater samples. 相似文献
3.
N. Negreira I. Rodríguez E. Rubí R. Cela 《Analytical and bioanalytical chemistry》2010,398(2):995-1004
The performance of the dispersive liquid–liquid microextraction (DLLME) technique for the determination of eight UV filters
and a structurally related personal care species, benzyl salicylate (BzS), in environmental water samples is evaluated. After
extraction, analytes were determined by gas chromatography combined with mass spectrometry detection (GC-MS). Parameters potentially
affecting the performance of the sample preparation method (sample pH, ionic strength, type and volume of dispersant and extractant
solvents) were systematically investigated using both multi- and univariant optimization strategies. Under final working conditions,
analytes were extracted from 10 mL water samples by addition of 1 mL of acetone (dispersant) containing 60 μL of chlorobenzene
(extractant), without modifying either the pH or the ionic strength of the sample. Limits of quantification (LOQs) between
2 and 14 ng L−1, inter-day variability (evaluated with relative standard deviations, RSDs) from 9% to 14% and good linearity up to concentrations
of 10,000 ng L−1 were obtained. Moreover, the efficiency of the extraction was scarcely affected by the type of water sample. With the only
exception of 2-ethylhexyl-p-dimethylaminobenzoate (EHPABA), compounds were found in environmental water samples at concentrations between 6 ± 1 ng L−1 and 26 ± 2 ng mL−1. 相似文献
4.
Development of a cloud point extraction and preconcentration method for silver prior to flame atomic absorption spectrometry 总被引:1,自引:0,他引:1
The possibility was investigated of using 2-mercaptobenzothiazole (MBT) for Ag(I) concentration by micellar extraction at
cloud point (CP) temperature and subsequent determination by flame atomic absorption spectrometry (FAAS). The method is based
on the complexation of Ag(I) with 2-mercaptobenzothiazole (MBT) in the presence of non-ionic micelles of Triton X-114. The
effect of experimental conditions such as pH, concentration of chelating agent and surfactant, equilibration temperature and
time on cloud point extraction was studied. Under the optimum conditions, the preconcentration of 10 mL of water sample in
the presence of 0.1% Triton X-114 and 2 × 10−4 mol L−1 2-mercaptobenzothiazole permitted the detection of 2.2 ng mL−1 silver. The calibration graph was linear in the range of 10–200 ng mL−1, and the recovery of more than 99% was achieved. The proposed method was used in FAAS determination of Ag(I) in water samples. 相似文献
5.
A novel method for the determination of proteins at nanogram levels was proposed based on the decrease of resonance light
scattering (RLS) signal resulting from the interaction of dibromo-o-nitrophenylfluorone (DBONPF)-sodium lauroyl glutamate
(SLG) with proteins. At pH 2.97, the decrease RLS intensity was proportional to the concentration of proteins in the range
of nanogram levels with 3σ detection limits being 3.4 ng mL−1 for bovine serum albumin (BSA), 1.7 ng mL−1 for human serum albumin (HSA), 4.1 ng mL−1 for γ-globulin (γ-IgG), 4.4 ng mL−1 for egg albumin, 6.2 ng mL−1 for pepsin (Pep) and 3.7 ng mL−1 for α-chymotrypsin (Chy). The method is no protein-to-protein variability, simple, rapid, practical and relatively free
from interference from coexisting substance, as well as much more sensitive than most of the reported methods. The proposed
method was successfully applied to determine total protein in human serum samples. 相似文献
6.
Zhefeng Fan 《Mikrochimica acta》2005,152(1-2):29-33
A sensitive and simple method for flame atomic absorption spectrometry (FAAS) determination of antimony species after separation/preconcentration
by cloud point extraction (CPE) has been developed. When the system temperature is higher than the cloud point extraction
temperature, the complex of antimony (III) with N-benzoyl-N-phenyhydroxylamine (BPHA) can enter the surfactant-rich phase,
whereas the antimony (V) remains in the aqueous phase. Antimony (III) in surfactant-rich phase was analyzed by FAAS and antimony
(V) was calculated by subtracting of antimony (III) from the total antimony after reducing antimony (V) to antimony (III)
by L-cysteine. The main factors affecting the cloud point extraction, such as pH, concentration of BPHA and Triton X-114,
equilibration temperature and time, were investigated systematically. Under optimized conditions, the detection limits (3σ)
were 1.82 ng mL−1 for Sb(III) and 2.08 ng mL−1 for Sb(total), and the relative standard deviations (RSDs) were 2.6% for Sb(III) and 2.2% for Sb(total). The proposed method
was applied to the speciation of antimony species in artificial seawater and wastewater, and recoveries in the range of 95.3–106%
were obtained by spiking real samples. This technique was validated by means of reference water materials and gave good agreement
with certified values. 相似文献
7.
Chunxia Wu Huimin Liu Weihua Liu Qiuhua Wu Chun Wang Zhi Wang 《Analytical and bioanalytical chemistry》2010,397(6):2543-2549
A simple dispersive liquid–liquid microextraction based on solidification of floating organic droplet coupled with high-performance
liquid chromatography–diode array detection was developed for the determination of five organophosphorus pesticides (OPs)
in water samples. In this method, the extraction solvent used is of low density, low toxicity, and proper melting point near
room temperature. The extractant droplet could be collected easily by solidifying it in the lower temperature. Some important
experimental parameters that affect the extraction efficiencies were optimized. Under the optimum conditions, the calibration
curve was linear in the concentration range from 1 to 200 ng mL−1 for the five OPs (triazophos, parathion, diazinon, phoxim, and parathion-methyl), with the correlation coefficients (r) varying from 0.9991 to 0.9998. High enrichment factors were achieved ranging from 215 to 557. The limits of detection were
in the range between 0.1 and 0.3 ng mL−1. The recoveries of the target analytes from water samples at spiking levels of 5.0 and 50.0 ng mL−1 were 82.2–98.8% and 83.6–104.0%, respectively. The relative standard deviations fell in the range of 4.4% to 6.3%. The method
was suitable for the determination of the OPs in real water samples. 相似文献
8.
Viñas P López-García I Bravo-Bravo M Briceño M Hernández-Córdoba M 《Analytical and bioanalytical chemistry》2012,403(4):1059-1066
A miniaturized dispersive liquid–liquid microextraction (DLLME) procedure coupled to liquid chromatography (LC) with fluorimetric
detection was evaluated for the preconcentration and determination of thiamine (vitamin B1). Derivatization was carried out by chemical oxidation of thiamine with 5 × 10−5 M ferricyanide at pH 13 to form fluorescent thiochrome. For DLLME, 0.5 mL of acetonitrile (dispersing solvent) containing
90 μL of tetrachloroethane (extraction solvent) was rapidly injected into 10 mL of sample solution containing the derivatized
thiochrome and 24% (w/v) sodium chloride, thereby forming a cloudy solution. Phase separation was carried out by centrifugation, and a volume of
20 μL of the sedimented phase was submitted to LC. The mobile phase was a mixture of a 90% (v/v) 10 mM KH2PO4 (pH 7) solution and 10% (v/v) acetonitrile at 1 mL min−1. An amide-based stationary phase involving a ligand with amide groups and the endcapping of trimethylsilyl was used. Specificity,
linearity, precision, recovery, and sensitivity were satisfactory. Calibration graph was carried out by the standard additions
method and was linear between 1 and 10 ng mL−1. The detection limit was 0.09 ng mL−1. The selectivity of the method was judged from the absence of interfering peaks at the thiamine elution time for blank chromatograms
of unspiked samples. A relative standard deviation of 3.2% was obtained for a standard solution containing thiamine at 5 ng mL−1. The esters thiamine monophosphate and thiamine pyrophosphate can also be determined by submitting the sample to successive
acid and enzymatic treatments. The method was applied to the determination of thiamine in different foods such as beer, brewer’s
yeast, honey, and baby foods including infant formulas, fermented milk, cereals, and purees. For the analysis of solid samples,
a previous extraction step was applied based on an acid hydrolysis with trichloroacetic acid. The reliability of the procedure
was checked by analyzing a certified reference material, pig’s liver (CRM 487). The value obtained was 8.76 ± 0.2 μg g−1 thiamine, which is in excellent agreement with the certified value, 8.6 ± 1.1 μg g−1. 相似文献
9.
Pedrón I Chisvert A March JG Salvador A Benedé JL 《Analytical and bioanalytical chemistry》2011,400(2):595-601
A novel and simple device for membrane-assisted liquid-phase microextraction is used for the first time in a three-phase system.
The device consists of a glass vial containing the aqueous acceptor phase, whose septum of its screw stopper has been replaced
by a sized piece of polytetrafluoroethylene membrane impregnated with n-decane. The vial is assembled to a volumetric flask containing the aqueous donor phase, and the membrane comes in contact
alternatively with both donor and acceptor aqueous phases by orbital agitation. The device has been tested for the determination
of nitrite in tap water samples, which is extensively carried out in routine analysis, as model analytical application. Experimental
variables, such as the organic solvent used to form the supported liquid membrane, the volumes of both donor and acceptor
phases, the orbital agitation rate, and the extraction time were studied and optimized in terms of enrichment factor. Under
the selected working conditions, the analytical figures of merit for nitrite determination were a linearity range up to 50 ng mL−1, limits of detection and quantification of 0.15 and 0.50 ng mL−1, respectively, and a good repeatability (RSD < 10%). The method has been applied to four tap water samples of different origins,
and accurate and precise results were achieved. Besides, the very low volume of organic solvent used, its low cost and the
no-risk of cross-contamination are significant operational advantages. 相似文献
10.
This work describes an effective, low solvent consumption and affordable sample preparation approach for the determination
of eight UV filters in surface and wastewater samples. It involves sorptive extraction of target analytes in a disposable,
technical grade silicone disc (5 mm diameter × 0.6 mm thickness) followed by organic solvent desorption, large volume injection
(LVI), and gas chromatography-mass spectrometry determination. Final working conditions involved overnight extraction of 100-mL
samples, containing 10% of methanol, followed by analytes desorption with 0.2 mL of ethyl acetate. The method provides linear
responses between the limits of quantification (from 0.003 to 0.040 ng mL−1) and 10 ng mL−1, an intra-day precision below 13%, and low matrix effects for surface, swimming pool, and treated sewage water samples. Moreover,
the extraction yields provided by silicone discs were in excellent agreement with those achieved using polydimethylsiloxane-covered
stir bars. Several UV filters were found in surface and sewage water samples, with the maximum concentrations corresponding
to octocrylene. 相似文献
11.
Ning Zhang Qing-Cheng Kong Zhen-Zhen Chen Ke-Hua Xu Bo Tang 《Mikrochimica acta》2007,158(1-2):165-171
A sensitive catalytic kinetic spectrofluorimetric approach for determining ng mL−1 levels of rhodium is presented, and the possible mechanism of the catalytic reaction was investigated. The determination
is based on the catalytic property of rhodium to enhance the reaction of o-vanillin salicylhydrazone (OVSH) with potassium
bromate in a water-ethanol medium at pH 4.80 and 45 °C. The presence of β-cyclodextrin (β-CD) obviously sensitized the assay
due to its high inclusion ability towards OVSH. Under optimized experimental conditions, fluorescence measurements of the
β-CD-rhodium-KBrO3-OVSH catalytic kinetic reaction system were carried out in its fluorescent band centered at λex = 333 nm and λem = 476 nm, respectively. The calibration graph was linear over the concentration range of 0.47–100 ng mL−1 with a detection limit of 0.14 ng mL−1. The effect of interferences was discussed, and the results show that the extraction method can be used to separate rhodium
from interference species such as iridium. The proposed method, applied to several synthetic mixtures containing rhodium mixed
with varying amounts of metal salts, produced satisfactory results. 相似文献
12.
Jibrin Sabo Suleiman Bin Hu Xuli Pu Chaozhang Huang Zucheng Jiang 《Mikrochimica acta》2007,159(3-4):379-385
A new method is proposed using a microcolumn (20 mm × 2.0 mm) packed with nanometer-sized zirconia as solid-phase extractor
for the separation/preconcentration of Mn, Cu, Cr, Zn, Ni and Co prior to their determination by inductively coupled plasma
optical emission spectrometer (ICP-OES) in environmental samples. The factors affecting the separation and preconcentration
of analytes such as pH, sample flow rate and volume, eluent concentration and volume were determined, interfering ions were
studied, and the optimal experimental conditions were established. The adsorption capacity of nanometer-sized ZrO2 for Mn, Cu, Cr, Zn, Ni and Co was found to be 1.3, 1.3, 1.7, 2.0, 3.9 and 1.5 mg g−1, respectively. The detection limits of the method were 12, 58, 24, 2, 7 and 36 ng L−1, respectively, with a preconcentration factor of 25. The precision of this method was 1.7% (Mn), 2.9% (Cu), 5.9% (Mn), 3.8%
(Mn), 6.2% (Mn) and 4.3% (Mn) with 9 determinations of 10 ng mL−1 of target analytes, respectively. The method was successfully applied to the determination of trace metals in lake water,
dried fish samples, certified reference materials of human hair and milk, and provided satisfactory results. 相似文献
13.
Ming-Zhou Zhang Min-Zi Wang Zong-Lun Chen Jie-Hong Fang Mei-Ming Fang Jun Liu Xiao-Ping Yu 《Analytical and bioanalytical chemistry》2009,395(8):2591-2599
A multianalyte lateral-flow immunochromatographic technique using colloidal gold-labeled polyclonal antibodies was developed
for the rapid simultaneous detection of clenbuterol and ractopamine. The assay procedure could be accomplished within 5 min,
and the results of this qualitative one-step assay were evaluated visually according to whether test lines appeared or not.
When applied to the swine urines, the detection limit and the half maximal inhibitory concentration (IC50) of the test strip under an optical density scanner were calculated to be 0.1 ± 0.01 ng mL−1 and 0.1 ± 0.01 ng mL−1, 0.56 ± 0.08 ng mL−1, and 0.71 ± 0.06 ng mL−1, respectively, the cut-off levels with the naked eye of 1 ng mL−1 and 1 ng mL−1 for clenbuterol and ractopamine were observed. Parallel analysis of swine urine samples with clenbuterol and ractopamine
showed comparable results obtained from the multianalyte lateral-flow test strip and GC-MS. Therefore, the described multianalyte
lateral-flow test strip can be used as a reliable, rapid, and cost-effective on-site screening technique for the simultaneous
determination of clenbuterol and ractopamine residues in swine urine.
相似文献
14.
A novel sensitive and simple method for rapid and selective extraction, preconcentration and determination of iron (as its
bathophenanthroline complex) and copper (as its neocuproine complex) using octadecyl silica cartridges and dual wavelength
spectrophotometry is presented. The dual wavelength method (533 nm for the iron-bathophenanthroline and 454 nm for the copper-neocuproine
as the analytical wavelength) is used to eliminate spectral interferences. Extraction efficiency and the influence of flow
rates of sample solution and eluent, pH, amount of neocuproine, bathophenanthroline and hydroxylamine hydrochloride, type
and least amount of eluent for elution of iron and copper complexes from cartridge, break-through volume and limit of detection
are evaluated. The effects of various cationic and anionic interferences on percent recovery of iron and copper are also studied.
Extraction efficiencies >95% are obtained by elution of cartridges with minimal amount of organic solvent. Iron and copper
were determined in the range of 3–100 ng mL−1. The limits of detection are 0.98 and 1.13 ng mL−1 for iron and copper, respectively. The proposed method is applied successfully to the determination of both analytes in river,
tap and well water samples.
Author for correspondence. E-mail: yyamini@modares.ac.ir
Received September 18, 2002; accepted December 12, 2002
Published online May 5, 2003 相似文献
15.
Jamshid L. Manzoori Hossein Abdolmohammad-Zadeh Mohammad Amjadi 《Mikrochimica acta》2007,159(1-2):71-78
A simple and sensitive cloud point extraction method has been developed for the preconcentration of ultra-trace amounts of
gold as a prior step to its determination by electrothermal atomic absorption spectrometry. It is based on the extraction
of gold in hydrochloric acid medium using the non-ionic surfactant polyethyleneglycolmono-p-nonylphenylether (PONPE 7.5) without adding a chelating agent. The preconcentration of a 50 mL sample solution was thus enhanced
by a factor of 200. The resulting calibration graph was linear in the range of 10–200 ng L−1 with a correlation coefficient of 0.9993. The limit of detection (3s) obtained under optimal conditions was 2.0 ng L−1. The relative standard deviation for 10 replicate determinations at a 100 ng L−1 Au level was 3.6%. The method was applied to the ultra-trace determination of gold in water and copper samples. 相似文献
16.
Bagheri H Aghakhani A Akbari M Ayazi Z 《Analytical and bioanalytical chemistry》2011,400(10):3607-3613
A micro-solid phase extraction technique was developed using a novel polypyrrole-polyamide nanofiber sheet, fabricated by
electrospinning method. The applicability of the new nanofiber sheet was examined as an extracting medium to isolate malathion
as a model pesticide from aqueous samples. Solvent desorption was subsequently performed in a microvial, and an aliquot of
extractant was injected into gas chromatography–mass spectrometry. Various parameters affecting the electrospinning process
including monomer concentration, polyamide content, applied voltage, and electrospinning time were examined. After fabricating
the most suitable preparation conditions, influential parameters on the extraction and desorption processes were optimized.
The developed method proved to be rather convenient and offers sufficient sensitivity and good reproducibility. The limit
of detection (S/N = 3) and limit of quantification (S/N = 10) of the method under optimized conditions were 50 and 100 ng L−1, respectively. The relative standard deviation at concentration level of 1 ng mL−1 was 2% (n = 3). The calibration curve of analyte showed linearity in the range of 0.1–1 ng mL−1 (R
2 = 0.9975). The developed method was successfully applied to tap and Zayanderood river water samples, while the relative recovery
percentages of 98% and 96% were obtained, respectively. The whole procedure showed to be conveniently applicable and quite
easy to be manipulated. 相似文献
17.
The chemiluminescence (CL) of peracetic acid (PAA) in alkaline medium is very weak but is strongly enhanced after the addition
of dihydralazine sulfate (DHZS). Based on this phenomenon, a simple, rapid and highly sensitive flow-injection CL method for
the determination of DHZS was developed. The CL emission was linearly related to the DHZS concentration in the range of 20–4000 ng mL−1 with a detection limit (3σ) of 1.2 ng mL−1. As a preliminary application, the proposed method was successfully applied to the determination of DHZS in pharmaceutical
preparations; the recovery of DHZS in human urine was between 96.5% and 102.2%. A detailed CL mechanism was proposed and singlet
molecular oxygen (1O2) was suggested to be produced in the CL reaction process. 相似文献
18.
Determination of trace elements in AR grade alkali salts after preconcentration by column solid-phase extraction on TiO2 (anatase) 总被引:1,自引:0,他引:1
Column solid-phase extraction using TiO2 (anatase) as a solid sorbent was applied to preconcentrate traces of Cd, Co, Cu, Fe, Mn, Ni and Pb from AR grade alkali salts
prior to their measurements by atomic absorption spectrometry (AAS). Multi-element preconcentration was achieved from NaCl, KCl,
KNO3, NaNO3, CH3COONa, NaHCO3 and Na2CO3 solutions, whereas the sorption of trace elements from phosphates and sulfates is not quantitative. Optimal conditions (recoveries
of the analytes >95%) for solid-phase co-extraction of the most common heavy metal ions are proposed. The conditions for quantitative
and reproducible elution and subsequent AAS are established. A method of determination of trace elements in different salts
is proposed. It is characterized by precision, reproducibility and a high preconcentration factor. The solid-phase extraction
by TiO2, combined with ETAAS allows the determination of 0.1 ng g-1 Cd, 2 ng g-1 Co, 1 ng g-1 Cu and Ni, 0.5 ng g-1 Mn and 0.4 ng g-1 Pb.
Received: 1 April 1996/Revised: 24 June 1996/Accepted: 9 July 1996 相似文献
19.
Simple and rapid fluorometric screening methods have been developed based on the competitive binding between the target and
an intercalating fluorophore dye to double-stranded-DNA (dsDNA). In this study, the long-wavelength fluorescente dye TOTO-3
was employed as the indicator. Compounds that interact with dsDNA will affect the binding of TOTO-3 to the nucleic acid thereby
changing the fluorescence intensity. The analyte concentration is indirectly determined by the decrease in fluorescence intensity.
A fiber optic fluorescence screening system was developed for rapid and convenient sample processing. Lambda DNA (48.5 kb)
was chosen as a suitable sensing nucleic acid material. Detection of sulfathiazole and chloramphenicol in shrimps using this
method was studied in the range of 0.5–25 ng mL−1 of sulfathiazole and of 1–50 ng mL−1 of chloramphenicol. Detection limits of 0.5 ng mL−1 of sulfathiazole and 1 ng mL−1 of chloramphenicol were achieved. This approach is useful as a routine test in the monitoring of antibiotics in the environment
or aquaculture products. The easy operation and the rapid and sensitive detection make this a potential high-throughput screening
method. 相似文献
20.
A novel adsorbent of chitosan chemically modified ordered mesoporous silica was synthesized and employed as a solid phase extraction (SPE) material for flow injection (FI) micro-column preconcentration on-line coupled with inductively coupled plasma optical emission spectrometry (ICP-OES) determination of trace heavy metals V, Cu, Pb, Cd and Hg in environmental water samples. The factors affecting separation and preconcentration of target heavy metals such as pH, sample flow rate and volume, eluent concentration and volume, interfering ions were investigated. Under the optimized experimental conditions, an enrichment factor of 20 and sampling frequency of 10 h−1 were obtained. The detection limits of the method for V, Cu, Pb, Cd and Hg were 0.33, 0.30, 0.96, 0.05 and 0.93 ng mL−1, and the relative standard deviations (RSDs) were 2.8%, 6.7%, 1.8%, 4.0% and 5.3% (n = 7, C = 10 ng mL−1), respectively. The adsorption capacities of chitosan modified ordered mesoporous silica for V, Cu, Pb, Cd, and Hg were found to be 16.3, 21.7, 22.9, 12.2 and 13.5 mg g−1, respectively. In order to validate the developed method, a certified reference material of GSBZ50009-88 environmental water sample was analyzed and the determined values were in good agreement with the certified values. The proposed method has also been applied to the determination of trace heavy metals in natural water samples with satisfactory results. 相似文献