Ultrasound-assisted Dispersive Micro Research Articles

One-pot/one-step synthesis of Bi2O3/ZnO/Pd nanocomposite for preconcentration and determination of some heavy metal ions in different samples

ABSTRACT In this contribution, a new green eco-friendly synthesised nanocomposite (Bi2O3/ZnO/Pd) was fabricated by one-pot/one-step method, using ultrasonic waves. The nanocomposite was used for pre-concentration of some heavy metals, i.e. cadmium (II), lead (II), and copper (II), exploiting ultrasound-assisted dispersive micro solid phase extraction (UA-D-μ-SPE) method, before their determination by flame atomic absorption spectroscopy (FAAS). The adsorbent synthesis was confirmed by XRD, SEM, BET, TEM, EDS, and TGA analyses. The central composite design (CCD) method was employed to optimise various parameters affecting the extraction of heavy metals. The effective parameters in the adsorption process, viz. the amount of adsorbent (16 mg), pH of the sample solution (6.2), and adsorption time (4 min), were optimised. The type and the concentration of eluting agent (HCl solution) was investigated as one parameter at a time. Impressive parameters in the desorption stage such as the volume and concentration of eluting solution (400 μL of 0.8 mol L−1 HCl) and desorption time (2.5 min) were optimised. In the best extraction conditions for cadmium (II), lead (II), and copper (II), the limits of detection (LODs) were 0.75, 2.1, and 0.90 ng mL−1; the limits of quantification (LOQs) were 2.5, 7.0, and 3.0 ng mL−1; the linear dynamic ranges (LDRs) were 2.5–100, 7.0–600, and 3.0–250 ng mL−1; preconcentration factors (PF) were 24.10, 25.20, and 25.39; and the relative standard deviations (RSDs%) were 3.7, 4.1, and 3.8 (n = 5), respectively. Additionally, the adsorbent had the ability to extract metals up to 8 times without a significant decrease in the extraction percentages. The adsorbent was successfully used in the determination of cadmium (II), lead (II), and copper (II) ions in different food, biological, cosmetic, and water samples.

Application of MgF2 as a new sorbent for preconcentration and isolation of sulphur in food samples before the determination by molecular absorption spectrometry

This study proposes, for the first time, the development of an analytical method using the new sorbent - magnesium fluoride (MgF2) and ultrasound-assisted dispersive micro solid-phase extraction (UA DMSPE) for accurate preconcentration and isolation of sulphur in food samples. The further determination was conducted with high-resolution continuum source electrothermal molecular absorption spectrometry (HR-CS ET MAS). The main UA DMSPE parameters were investigated. Satisfying extraction efficiencies were obtained using 10 mL of sample solution, 20 mg of MgF2 and 20 s extraction time. The limit of detection and the preconcentration factor were 0.001 μg mL−1 and 18, respectively, and no matrix effect was observed. The relative standard deviation (RSD) was 2–13%. The proposed method was applied, inter alia, to corn flakes and flour, dried raisins and goji berries as well as different types of tea leaves. The accuracy of the developed method was evaluated by analysis of certified reference materials: mixed polish herbs (INCT-MPH-2), soya bean flour (INCT-SBF-4), tea leaves (INCT-TL-1), wheat (NCS ZC73009) and corn (NCS ZC73010). Sulphur concentrations determined in these materials were in satisfactory agreement with the certified values (recoveries in the range of 94% to 101%).

Covalent organic framework as adsorbent for ultrasound-assisted dispersive (micro)solid phase extraction of polycyclic synthetic fragrances from seawater followed by fluorescent determination

In this work, a new analytical approach based on ultrasound-assisted dispersive (micro)solid phase extraction (US-D-μSPE) using TpBD-Me2 covalent organic framework (COF) as adsorbent for simple, rapid and selective fluorescent determination of two polycyclic synthetic fragrances in seawater, i.e., 1,3,4,6,7,8-hexahydro-4,6,6,7,8,8-hexamethyl-cyclopenta-(γ)-2-benzopyran (HHCB), branded galaxolide®, and 7-acetyl-1,1,3,4,4,6-hexamethyltetralin (AHTN), branded tonalide®, is proposed. Different parameters involved in both adsorption and desorption steps were optimized in order to obtain the best results. High adsorption efficiencies in the range of 91.2–97.8% were achieved for both analytes. Desorption efficiencies of ∼98% for AHTN and HHCB were obtained using methanol as solvent, rendering the material recyclable with merely minor losses in adsorption efficiency after five consecutive cycles of adsorption/desorption. Limits of detection (LODs) were 0.082 μg L−1 and 0.070 μg L−1 for AHTN and HHCB, respectively. The proposed method was successfully applied for the analysis of seawater without the need for a previous sample treatment, e.g., pH adjustment. Recoveries in the range of 90.4–101.2% with a relative standard deviation of 5.8% were obtained for both fragrances. The results proved the great capacity of TpBD-Me2 COF for the selective sorption of polycyclic fragrances in combination with fluorescent detection, being highly promising for application to environmental monitoring of other emerging organic pollutants.

Development of ultrasound assisted dispersive micro solid phase extraction based on CuO nanoplate-polyaniline composite as a new sorbent for insecticides analysis in wheat samples

A simple, fast and highly sensitive preconcentration method based on dispersive micro-solid phase extraction (D-µSPE) was developed using CuO nano plate-polyaniline composite (CNPC). The method was applied for the determination of diazinon and imidacloprid insecticides followed by high performance liquid chromatography (HPLC) analysis. The sorbent was characterized by scanning electron microscopy (SEM), Fourier transform- infrared (FT-IR) and x-ray detection (XRD). Experimental design was applied for optimization of the effective parameters on the extraction efficiency such as sample pH, extraction and desorption times, ionic strength and eluent volume. Optimized conditions were obtained as sample pH of 8.0, 100 µl of eluent, adsorption and desorption times of 12.5 and 23 min, respectively and 30% (w/v) of NaCl when 11 mg of the sorbent was applied. The adsorption isotherms were investigated for diazinon and imidacloprid and the results showed better fitness with the Langmuir model. The adsorption capacity of CNPC for diazinon and imidacloprid were calculated 12.18 and 2.58 mg g−1, respectively. Under the optimized conditions, limits of detection of 3 and 0.056 µg Kg−1 and relative standard deviations of 1.7% and 3.7% were obtained for diazinon and imidacloprid, respectively. Relative recoveries up to 99% were achieved indicating good adsorption efficiency of the sorbent. Finally, the developed method was successfully applied for the determination of trace amount of the target analytes in grain samples.

Magnetic dispersive micro-solid phase extraction merged with micro-sampling flame atomic absorption spectrometry using (Zn-Al LDH)-(PTh/DBSNa)-Fe3O4 nanosorbent for effective trace determination of nickel(II) and cadmium(II) in food samples

In this work, Zn-Al layered double hydroxide (Zn-Al LDH) combined with polythiophene (PTH)/sodium dodecyl benzene sulfonate (DBSNa) and Fe3O4 was synthesized and used in a centrifugeless ultrasound-assisted dispersive micro solid phase extraction (UA-D-μSPE) technique for pre-concentration and separation of Ni2+ and Cd2+ ions. The final analysis of the analytes was carried out by the micro sampling flame atomic absorption spectrometry (MS-FAAS). The influences of several effective analytical parameters, including pH value, amount of nanosorbent, sonication time, and eluent volume, on the extraction efficiency were studied by experimental design method. In the optimal conditions, the linearity ranges of 5–300 and 2.5–100 ng mL−1 for the Ni2+and Cd2+ ions were attained, respectively. The limits of detection (LODs) of the method were 1.3 and 0.7 ng mL−1 for the Ni2+ and Cd2+ ions, respectively. The proposed method demonstrated to be suitable for concurrent extraction of studied metals in various vegetable and meat samples with high accuracy and enrichment factors.

Speciation of cadmium in human blood samples based on Fe3O4-supported naphthalene-1-thiol- functionalized graphene oxide nanocomposite by ultrasound-assisted dispersive magnetic micro solid phase extraction

Cadmium (Cd) has toxic effect in human body and exists as the inorganic (Cd2+) and organic (R-Cd) forms in human biological matrix. Due to cadmium toxicity in various forms, the speciation of cadmium in human blood samples is very important. In this study, the Fe3O4-supported naphthalene-1-thiol- functionalized graphene oxide (Fe3O4@NpSH-GO, NMNT-GO) as a novel nanomagnetic composite was used for cadmium speciation in blood samples by ultrasound-assisted dispersive magnetic micro solid phase extraction (USA-DM-μ-SPE). By procedure, 20 mg of the NMNT-GO was used for extraction of Cd(II) from 1 mL of human blood samples at pH = 6.0, before determined by electrothermal atomic absorption spectrometry (ET-AAS). The total cadmium (T-Cd) was obtained by converting organic (R-Cd) to inorganic form (Cd2+), before adjusting pH and continuing with USA-DM- μ-SPE procedure. The organic cadmium was simply calculated by subtracting total cadmium from inorganic cadmium content. In optimized conditions, the linear range (peak area), limit of detection (LOD) and the preconcentration factor were obtained 30–1520 ng L−1, 10 ng L−1 and 4.88 in human blood samples, respectively (RSD: 1.1 %). The adsorption capacities of the Fe3O4@NpSH-GO and the GO were achieved 185.3 mg g−1 and 33.7 mg g−1 for inorganic cadmium, respectively. The results were validated by certified reference materials (CRM, NIST) and inductively coupled plasma mass spectrometry (ICP-MS) in human blood samples.

Aluminum separation from drinking water and serum samples based on djenkolic acid immobilized on the multi walled carbon nanotubes by ultrasound-assisted dispersive micro solid phase extraction

A new method for aluminum extraction from drinking water and human serum samples was used by djenkolic acid (DJKA) immobilized on multi-walled carbon nanotubes (MWCNTs-DJKA).   In the optimized study, LOD, LOQ,  the linear range, the working range, and the enrichment factor were obtained 0.1 µg L−1, 0.3 µg L−1, 0.3-12.8 µg L−1, 0.3-30.7 µg L−1 and 9.92, respectively (RSD< 5%). The adsorption capacity of the MWCNTs-DJKA and MWCNTs sorbent was achieved 122.6 mg g-1 and 33.7 mg g-1 in the batch system for 20 min, respectively. The mean aluminum in drinking water and serum samples were obtained 48.56 ± 2.92 and 11.64 ± 0.73 which was lower than the reference value in drinking water and human biological samples. The method was validated by spiking samples and standard reference materials (SRM) in water and human biological samples. 

Reversible chelating polymer for determination of heavy metals by dispersive micro solid-phase extraction with ICP-MS.

N-functionalization of pyrrole with carbon disulfide and subsequent chemical polymerization resulted in the development of a new sorbent material for the extraction of metals. The synthesized polymer, poly(pyrrole-N-carbodithioic acid) (PPy-CS2), is an air-stable, granular powder that is insoluble in water. PPy-CS2 combines pH-dependent chelation, extraction, and desorption sorbent properties that are exploited for the selective extraction and sensitive determination of heavy metals in water matrices using ultrasound-assisted dispersive micro solid-phase extraction and inductively coupled plasma mass spectrometry. Excellent removal and recovery of Cd(II), Co(II), Cu(II), Ni(II), Pb(II), and Zn(II) were achieved and compared with unfunctionalized polypyrrole, which demonstrated extraction resulted from chelation of the metal ions. The extraction efficiency of the PPy-CS2 sorbent as a function of pH, amount of sorbent, extraction time, and flow rate of the desorption solution were evaluated. Limits of detection ranged from 0.3 for cadmium to 11.2ng/L for zinc with linear dynamic ranges from 0.1 to 500μg/L and relative standard deviations from 2.2 to 6.3%. The sample preparation method was successfully applied for determination of the target metals in raw well water, treated well water, and river water. Validation was performed by analysis of a certified reference standard for trace metals in drinking water. Graphical abstract Schematic representation of the ultrasound-assisted micro solid-phase extraction protocol for the removal and recovery of heavy metals by the air-stable, granular, and reversible chelating polymer, poly (pyrrole-N-carbodithioic acid).

Zinc ferrite as a magnetic sorbent for the dispersive micro solid-phase extraction of sulfonamides and their determination by HPLC

In this study, the use of zinc ferrites in a magnetic, ultrasound-assisted dispersive micro solid-phase extraction procedure for the determination of sulfonamides is developed. Zinc ferrites can efficiently and selectively extract sulfonamides from environmental and food matrixes. Their synthesis is straightforward, and the resulting material exhibits favorable magnetic properties for its harvesting, after extraction. As a proof of concept, an analytical method was developed for the determination of sulfonamides in lake water and egg samples using high-performance liquid chromatography with diode array detection. The new procedure exhibits low limits of quantification (0.06 up to 0.11 μg L−1), low matrix effect (from −8% to 8%), acceptable recoveries (88–101%) and satisfactory enrichment factors (111–141). Moreover, the method has a wide linear range (up to 250 μg L−1) making it possible to determine sulfonamides at concentrations above and below the maximum residue limit. Due to the aforementioned merits, the few synthetic steps required and the efficiency of sample preparation, the developed method can be used for the routine analysis of sulfonamides. Moreover, this study highlights the affinity of zinc for sulfonamides, a property that has never reaped before in analytical chemistry.

Slurry sampling thermospray flame furnace atomic absorption spectrometric determination of bismuth in water and geological samples combined with ultrasound-assisted dispersive micro solid phase extraction

UA-DMSPE was combined with TS-FF-AAS for the first time, and a sensitive method for the determination of bismuth was established.

Determination of Selenium in Food Samples by High-Resolution Continuum Source Atomic Absorption Spectrometry After Preconcentration on Halloysite Nanotubes Using Ultrasound-Assisted Dispersive Micro Solid-Phase Extraction

In this study, a preconcentration procedure was developed for the determination of selenium in food samples using high-resolution continuum source graphite furnace atomic absorption spectrometry (HR-CS GFAAS). Halloysite nanotubes (HNTs) were used as a solid sorbent in ultrasound-assisted dispersive micro solid-phase extraction (USA DMSPE) during the preconcentration step. The experimental parameters including pH of the sample solution, the amount of halloysite nanotubes, and ultrasonication time, as well as the main parameters of HR-CS GFAAS, were optimized. The limit of detection of total selenium was 0.01 μg/L and the achieved preconcentration factor was 18. The relative standard deviations (RSDs) were 6–9%. The accuracy of this method was validated by analyses of NIST SRM 1567a (wheat flour) and NIST SRM 1549 (non-fat milk powder) certified reference materials. Selenium contents measured in these reference materials were in satisfactory agreement with the certified values according to the t test for a 95% confidence level. The proposed method was successfully applied to the determination of selenium in food samples (corn flour, rice flour, oat flour, buckwheat flour, garlic, cranberries, goji berries, and raisins).

Synthesis of Fe3O4@CuS@Ni2P-CNTs magnetic nanocomposite for sonochemical-assisted sorption and pre-concentration of trace Allura Red from aqueous samples prior to HPLC-UV detection: CCD-RSM design

A simple procedure based on ultrasound-assisted (UA) dispersive micro solid phase extraction (D-μ-SPE) was applied for sorption of trace amount Allura Red (AR) in fruit juice and water samples. After loading process by UA-D-μ-SPE, the concentrated AR was eluted and monitored using high-performance liquid chromatography-ultraviolet -visible detector (HPLC-UV). The best operational conditions were obtained as follows: pH = 3.0, 8 mg of the sorbent, sonication time of 4.5 min and 0.16 mL of THF as elution solvent. Under the optimum operational conditions, the present method was acceptable for AR quantification in the range of 1.0–5000 ng mL−1. The repeatability based on RSD with the amount of 1.67–3.18%, low LOD (0.198 ng mL−1) and LOQ (0.659 ng mL−1) were obtained. The UA-D-μ-SPE-HPLC-UV method was successfully applied for trace quantification of AR from water and commercial fruit juice samples supplied from local supermarkets, and acceptable relative recoveries over the range of 97.7–105.4% with RSDs ≤5.50% were obtained.

Low cost adsorbents in ultrasound-assisted dispersive micro solid-phase extraction for simultaneous determination of indium and nickel by high-resolution continuum source graphite furnace atomic absorption spectrometry in soils and sediments

In this study, the analytical potential of USA DMSPE with bentonite clay as a low cost adsorbent combined with HR-CS GF AAS in the simultaneous determination of In and Ni was evaluated.

Sequential determination of gallium, indium, and thallium in environmental samples after preconcentration on halloysite nanotubes using ultrasound-assisted dispersive micro solid-phase extraction

A preconcentration procedure for gallium, indium, and thallium using HNTs was developed prior to their sequential determination by HR-CS GFAAS.

A facile and selective approach for enrichment of l-cysteine in human plasma sample based on zinc organic polymer: Optimization by response surface methodology

In this research, a facile and selective method was described to extract l-cysteine (l-Cys), an essential α-amino acid for anti-ageing playing an important role in human health, from human blood plasma sample. The importance of this research was the mild and time-consuming synthesis of zinc organic polymer (Zn-MOP) as an adsorbent and evaluation of its ability for efficient enrichment of l-Cys by ultrasound-assisted dispersive micro solid-phase extraction (UA-DMSPE) method. The structure of Zn-MOP was investigated by FT-IR, XRD and SEM. Analysis of variance (ANOVA) was applied for the experimental data to reach the best optimum conditions. The quantification of l-Cys was carried out by high performance liquid chromatography with UV detection set at λ=230nm. The calibration graph showed reasonable linear responses towards l-Cys concentrations in the range of 4.0–1000μg/L (r2=0.999) with low limit of detection (0.76μg/L, S/N=3) and RSD≤2.18 (n=3). The results revealed the applicability and high performance of this novel strategy in detecting trace l-Cys by Zn-MOP in complicated matrices.

Coupling of two centrifugeless ultrasound-assisted dispersive solid/liquid phase microextractions as a highly selective, clean, and efficient method for determination of ultra-trace amounts of non-steroidal anti-inflammatory drugs in complicated matrices

In this work, a new, simple, rapid, and environmentally friendly method with a high sample clean-up capability termed as centrifugeless ultrasound-assisted dispersive micro solid-phase extraction coupled with salting-out ultrasound-assisted liquid-liquid microextraction based on solidification of a floating organic droplet followed by high performance liquid chromatography is introduced for the first time. In this method, the three non-steroidal anti-inflammatory drugs diclofenac, ibuprofen, and mefenamic acid are first extracted based on an effective nanoadsorbent named as the layered double hydroxide-carbon nanotube nanohybrid. The first step provides a rapid and convenient way to separate the adsorbent from the sample matrix by a syringe nanofilter without additional centrifugation. In the next step, which is based upon the salting-out effect, after emulsification in the presence of ultrasonic irradiation, the phase separation is simply achieved through the salting-out phenomenon, and the extracting solvent is suspended on top of the sample solution. Under the optimal experimental conditions including the initial pH value of 6.0, 8.0 mg of the nanohybrid, 3 min ultrasonic time, 100 μL elution solvent (first step), secondary pH value of 3.0, 60 μL of 1-undecanol, 60 s ultrasonic time, and flow rate of 3 mL min−1 (second step), good responses were obtained for diclofenac, ibuprofen, and mefenamic acid in the concentration ranges of 0.8–2000, 0.8–2500, and 0.5–2000 ng mL−1, respectively, with low limits of detection ranging from 0.1 to 0.2 ng mL−1. The intra-day and inter-day precisions for the target analytes at the three concentration levels were in the ranges of 6.1–7.8% and 6.3–8.1%, respectively. The proposed method was also successfully applied to the biological and waste water samples, and excellent recoveries were obtained in the range of 92.9–103.1% even when the matrix was complex.

Determination of fluorine in herbs and water samples by molecular absorption spectrometry after preconcentration on nano-TiO2 using ultrasound-assisted dispersive micro solid phase extraction

This work presents ultrasound-assisted dispersive micro solid phase extraction (USA DMSPE) for preconcentration of fluorine (F) in water and herb samples. TiO2 nanoparticles (NPs) were used as an adsorbent. The determination with slurry sampling was performed via molecular absorption of calcium monofluoride (CaF) at 606.440 nm using a high-resolution continuum source electrothermal absorption spectrometry (HR-CS ET MAS). Several factors influencing the efficiency of the preconcentration technique, such as the amount of TiO2, pH of sample solution, ultrasonication and centrifugation time and TiO2 slurry solution preparation before injection to HR-CS ET MAS, were investigated in detail. The conditions of detection step (wavelength, calcium amount, pyrolysis and molecule-forming temperatures) were also studied. After extraction, adsorbent with the analyte was mixed with 200 μL of H2O to prepare a slurry solution. The concentration limit of detection was 0.13 ng mL−1. The achieved preconcentration factor was 7. The relative standard deviations (RSDs, %) for F in real samples were 3–15%. The accuracy of this method was evaluated by analyses of certified reference materials after spiking: INCT-MPH-2 (Mixed Polish Herbs), INCT-SBF-4 (Soya Bean Flour), ERM-CAO11b (Hard Drinking Water) and TMDA-54.5 (Lake Ontario Water). The measured F contents in reference materials were in satisfactory agreement with the added amounts, and the recoveries were found to be 97–109%. Under the developed extraction conditions, the proposed method has been successfully applied for the determination of F in real water samples (lake, sea, tap water) and herbs.

Fabrication of magnetic Fe3O4@nSiO2@mSiO2–NH2 core–shell mesoporous nanocomposite and its application for highly efficient ultrasound assisted dispersive µSPE-spectrofluorimetric detection of ofloxacin in urine and plasma samples

In this research, a sensitive, simple and rapid ultrasound assisted dispersive micro solid-phase extraction (USAD-µSPE) was developed using a synthesized core–shell magnetic mesoporous nanocomposite (Fe3O4@nSiO2@mSiO2–NH2) as an efficient adsorbent for the preconcentration and spectrofluorometric determination of ofloxacin (OFL) in biological samples. The synthesized adsorbent was characterized using FT-IR spectroscopy, transmission electron microscopy (TEM), vibrating sample magnetometer (VSM), energy dispersive X-ray (EDX) spectroscopy, thermogravimetric analysis (TGA) and Brunauer–Emmett–Teller (BET) analysis. The application of this magnetic nanocomposite as a sensitive solid phase for removal, preconcentration and spectrofluorometric quantification of trace amount of OFL was developed. Influence of various variables including pH, sorbent dosage, desorption solvent properties and sonication time on present method response was studied and optimized. The results showed that using the proposed method OFL can be determined in the linear concentration range of 1.0–500.0µgL−1 with a limit of detection as low as 0.21µgL−1 and relative standard deviation less than 2.5 (%). The results of human urine and blood plasma analysis showed that the method is a good candidate for biological sample analysis purposes.

ZnO nanoparticles as an adsorbent in ultrasound-assisted dispersive micro solid-phase extraction combined with high-resolution continuum source electrothermal atomic absorption spectrometry for determination of trace germanium in food samples

An ultrasound-assisted dispersive micro solid-phase extraction (USA DMSPE) is presented for the separation and preconcentration of trace levels of germanium with the use of zinc oxide nanoparticles (nano-ZnO) as an adsorbent prior to high-resolution continuum source electrothermal atomic absorption spectrometry (HR-CS ET AAS). The experimental parameters (amount of ZnO, pH of sample solution, ultrasonication and centrifugation time, ZnO slurry preparation) were studied. Effective preconcentration of trace germanium with 20mg of ZnO was achieved at pH9. After extraction, adsorbent with analyte was mixed with 200μL of H2O to prepare slurry. The concentration limit of detection was 0.003ng mL−1 for total Ge. The achieved preconcentration factor was 15. The relative standard deviations (RSDs, %) for determination of the analyte in real samples were 4–23%. The accuracy of this method was evaluated by the extraction and determination of total Ge after spiking of certified reference materials: INCT-TL-1 (Tea Leaves) and INCT-MPH-2 (Mixed Polish Herbs). The measured germanium contents were in satisfactory agreement with the added amounts (according to the t-test for a 95% confidence level). The presented method has been successfully applied for the determination of the analyte in real food samples (tea, goji berries, ginger products and aloe vera juice).

Halloysite nanotubes as a solid sorbent in ultrasound-assisted dispersive micro solid-phase extraction for the determination of bismuth in water samples using high-resolution continuum source graphite-furnace atomic absorption spectrometry

In this research, a simple, accurate, and inexpensive preconcentration procedure was developed for the determination of bismuth in water samples, using high-resolution continuum source graphite furnace atomic absorption spectrometry (HR CS GFAAS). During the preconcentration step, halloysite nanotubes (HNTs) were used as a solid sorbent in ultrasound-assisted dispersive micro solid-phase extraction (USA DMSPE). The influence of the pH of the sample solution, amount of HNTs, and extraction time, as well as of the main parameters of HR CS GFAAS, on absorbance was investigated. The limit of detection was 0.005μgL−1. The preconcentration factor achieved for bismuth was 32. The relative standard deviation (RSD) was 4%. The accuracy of this method was validated by analyses of NIST SRM 1643e (Trace elements in water) and TMDA-54.5 (A high level fortified sample for trace elements) certified reference materials. The measured bismuth contents in these certified reference materials were in satisfactory agreement with the certified values according to the t-test for a 95% confidence level. The proposed method has been successfully applied to the determination of bismuth in five different real water samples (seawater, lake water, river water, stream water and rain water).