Development of Dispersive Liquid‐Liquid Microextraction Based on Solidification of Floating Organic Drop for the Determination of Trace Cobalt in Water Samples

A liquid‐phase microextraction technique was developed using dispersive liquid‐liquid microextraction based on solidification of floating organic drop combined with flame atomic absorption spectrometry, for the extraction and determination of trace amounts of cobalt in water samples. Microextraction efficiency factors, such as the type and volume of extraction and dispersive solvents, pH, extraction time, the chelating agent amount, and ionic strength were investigated and optimized. Under optimum conditions, an enrichment factor of 160 was obtained from 10.0 mL of water sample. The calibration graph was linearin the range of 1.15‐110 μg L^?1 with a detection limit of 0.35 μg L^?1. The relative standard deviation for ten replicate measurements of 10 and 100 μg L^?1 of cobalt were 3.26% and 2.57%, respectively. The proposed method was assessed through the analysis of certified reference water or recovery experiments.     

Sensitive adsorptive stripping voltammetric method for direct determination of trace concentration of lead in the presence of cupferron in natural water samples

This paper reports the use of an adsorptive voltammetric technique for Pb(II) determination using cupferron as a selective complexing agent. After accumulation of the complex onto a hanging mercury drop electrode, the electrode potential was scanned with differential pulse modulation and the reduction current of lead was observed at about??0.5?V. Under optimum conditions (5?×?10^?4?mol?L^?1 cupferron concentration, 0.1?mol?L^?1 acetate buffer (pH 5.5), adsorption at??50?mV for 30?s) the detection limit was 5.1?×?10^?10?mol?L^?1. The relative standard deviation of five measurements for low lead concentration was 3.1%. The accuracy of the method was tested by analysing certified reference material (SPS-WW1 Waste Water). Finally, the method was successfully applied to the determination of Pb(II) in river water samples without any pretreatments.     

Multiwall Carbon Nanotube‐Ionic Liquid Modified Paste Electrode as an Efficient Sensor for the Determination of Diazepam and Oxazepam in Real Samples

A carbon‐based electrode using multiwall carbon nanotube as a modifier and room temperature ionic liquid as a binder has been applied for the determination of diazepam (DZP) and oxazepam (OZP) in real samples including serum, urine and tablets. Square wave voltammetry as an appropriate electrochemical technique was applied to achieve improved limits of detection and higher sensitivities. The electrochemical studies were investigated under various experimental conditions such as pH, buffer concentration, ionic strength, deposition potential, deposition time and scan rate to achieve higher sensitivities. Linear concentration ranges for DZP and OZP were 0.02–0.76 mg L^?1 and 0.05–1.90 mg L^?1 with the detection limits of 4.1 µg L^?1 and 5.8 µg L^?1, respectively. The proposed method was successfully applied for the analysis of commercially available tablets as well as serum and urine samples and satisfactory results were obtained.     

Sorbent separation and enrichment method for cobalt ions determination by graphite furnace atomic absorption spectrometry in water and urine samples using multiwall carbon nanotubes

A new cobalt ions pre-concentration method, optimised by fractional factorial design, using multiwall carbon nanotubes (MWCNTs) with further Graphite Furnace Atomic Absorption Spectrometry (GFAAS) quantification is described. The method explores the high chemical and physical stability of MWCNTs for improving the detectability of GFAAS. It is based on off-line pre-concentration of 20.0 mL of sample previously buffered (pH 8.82) on MWCNTs at a flow rate of 10.0 mL min^?1. After the pre-concentration procedure, the elution step was carried out with 500 µL of 0.524 mol L^?1 HNO₃ solution at a flow rate of 2.0 mL min^?1. Fractional factorial designs and response surface methodology were employed for optimisation of all chemical parameters involved in the pre-concentration procedure, including pre-concentration flow rate, buffer and eluent concentration, sample pH and elution volume. The method provides a linear calibration range from 0.03 up to 7.00 µg L^?1 with linear correlation coefficient higher than 0.9994 and limits of detection and quantification of 0.01 and 0.03 µg L^?1, respectively. Repeatability of the six measurements was found to be 2.38 and 1.84% for 0.3 and 4.5 µg L^?1 cobalt concentration, respectively. By pre-concentrating 20.0 mL of sample, a pre-concentration factor (PF) of 19.10-fold and a consumption index of 1.05 mL were obtained. The pre-concentration efficiency (PE) was found to be 9.55 min^?1. The proposed method was successfully applied for the pre-concentration and determination of cobalt in water and urine samples with satisfactory recovery values.     

Ligandless-ultrasound-assisted emulsification microextraction followed by inductively coupled plasma-optical emission spectrometry for simultaneous determination of heavy metals in water samples

In this study, a simple and efficient method of ligandless-ultrasound-assisted emulsification microextraction (LL-USAEME) followed by inductively coupled plasma-optical emission spectrometry (ICP-OES) has been developed for simultaneous extraction, preconcentration and determination of manganese, cadmium, cobalt and nickel in water samples. In the proposed approach, tetrachloroethylene was selected as extraction solvent. The effect of important experimental factors such as volume of extraction solvent, pH, sonication time, salt concentration, and temperature was investigated by using a fractional factorial design (2^5?1) to identify important factors and their interactions. In the next step, a Box-Behnken design (BBD) was applied for optimisation of significant factors. The obtained optimal conditions were: 30?µL for extraction solvent, 12 for pH, 5?min for sonication time, and 5% w/v for salt concentration. The limits of detections (LODs) for Cd(II), Co(II), Mn(II) and Ni(II) were 0.20, 0.13, 0.21 and 0.28?µg?L^?1, respectively. Relative standard deviations (RSD, C?=?200.0?µg?L^?1, n?=?9) were between 3.4–7.5% and the calibration graphs were linear in the range of 0.25 to 1000.0?µg?L^?1 for Mn, 0.5–1000.0?µg?L^?1 for Co and Ni and 1.0–250.0?µg?L^?1 for Cd. The determination coefficients (R ²) of the calibration curves for the analytes were in the range of 0.993 to 0.999. The proposed method was validated by using two certified reference materials, and also the method was applied successfully for the determination of heavy metals in different real water samples.     

Determination of triclosan and triclocarban in environmental water samples with ionic liquid/ionic liquid dispersive liquid-liquid microextraction prior to HPLC-ESI-MS/MS

A hydrophobic ionic liquid was finely dispersed in aqueous solution along with a hydrophilic ionic liquid. Following centrifugation, the two phases aggregate to form relatively large droplets. Based on this phenomenon, a method termed ionic liquid/ionic liquid dispersive liquid-liquid microextraction was developed. It was applied to the enrichment of triclosan (TCS) and triclocarban (TCC) from water samples prior to HPLC with electrospray tandem MS detection. The type and volume of the hydrophobic ionic liquid (the extraction solvent) and the hydrophilic ionic liquid (the disperser solvent), salt content, and extraction time were optimized. Under optimum conditions, the method gives a linear response in the concentration ranges from 0.5 to 100???g L^?1 for TCC and from 2.5 to 500???g L^?1 for TCS, respectively. The limits of detection are 0.23 and 0.35???g L^?1, and the repeatability is 5.4 and 6.4% for TCC and TCS, respectively. The method was validated with four environmental water samples, and average recoveries of spiked samples were in the range from 88% to 111%. The results indicate that the method is a promising new approach for the rapid enrichment and determination of organic pollutants.

Preconcentration of trace amounts of cobalt (II) ions in water and agricultural products samples using of 5-(4-dimethylaminobenzylidene) rhodanin modified SBA-15 sorbent prior to FAAS determination

In the present study, the ?5-(4-dimethylaminobenzylidene)rhodanin-modified SBA-15? was applied as stable solid sorbent for the separation and preconcentration of trace amounts of cobalt ions in aqueous solution. SBA-15 was modified by ?5-(4-dimethylaminobenzylidene)rhodanin reagent. The sorption of Co²⁺ ions was done onto modified sorbent in the pH range of 6.8–7.9 and desorption occurred in 5.0 mL of 3.0 mol L^?1 HNO₃. The results exhibit a linear dynamic range from 0.01 to 6.0 mg L^?1 for cobalt. Intra-day (repeatability) and inter-day (reproducibility) for 10 replicated determination of 0.06 mg L^?1 of cobalt was ±1.82% and ?±1.97%?. Detection limit was 4.2 µg L^?1 (3S_b, n = 5) and preconcentration factor was 80. The effects of the experimental parameters, including the sample pH, flow rates of sample and eluent solution, eluent type and interference ions were studied for the preconcentration of Co²⁺. The proposed method was applied for the determination of cobalt in standard samples, water samples and agricultural products.     

Sensitive determination of ATP using a carbon paste electrode modified with a carboxyl functionalized ionic liquid

We report on a new electrode for the determination of adenosine-5??-triphosphate (ATP). It is based on modified carbon paste electrode that contains an ionic liquid (IL) as the binder. The electrode shows strong electrocatalytic oxidative activity towards ATP at pH 4.5 in giving a well-defined single oxidation peak. The oxidation reaction is adsorption-controlled and due to the presence of the highly conductive IL. The electron transfer rate constant was calculated to be 2.04×10^?C3 s^?C1, and the surface coverage is 1.11×10^?C10 mol cm^?C2. Under the selected conditions, the oxidation peak current changes linearly with the concentration of ATP in the range from 5.0 to 1000???mol L^?1 and a detection limit of 1.67???mol L^?1 (3???) as determined by differential pulse voltammetry. The method displays good selectivity and was applied to the determination of ATP injection samples with satisfactory results.

Determination of cobalt in water samples by atomic absorption spectrometry after pre-concentration with a simple ionic liquid-based dispersive liquid-liquid micro-extraction methodology

A rapid dispersive liquid-liquid micro-extraction (DLLME) methodology based on the application of 1-hexylpyridinium hexafluorophosphate [C₆py][PF₆] ionic liquid (IL) as an extractant solvent was applied for the pre-concentration of trace levels of cobalt prior to determination by flame atomic absorption spectrometry (FAAS). 1-Phenyl-3-methyl-4-benzoyl-5-pyrazolone (PMBP) was employed as a chelator forming a Co-PMBP complex to extract cobalt ions from aqueous solution into the fine droplets of [C₆py][PF₆]. Some effective factors that influence the micro-extraction efficiency include the pH, the PMBP concentration, the amount of ionic liquid, the ionic strength, the temperature and the centrifugation time which were investigated and optimized. In the optimum experimental conditions, the limit of detection (3s) and the enrichment factor were 0.70 μg L⁻¹ and 60, respectively. The relative standard deviation (RSD) for six replicate determinations of 50 μg L⁻¹ Co was 2.36%. The calibration graph using the pre-concentration system was linear at levels 2–166 μg L⁻¹ with a correlation coefficient of 0.9982. The applicability of the proposed method was evaluated by the determination of trace amounts of cobalt in several water samples.      

Preconcentration of cobalt using Amberlyst 36 as a solid-phase extractor and its determination in various environmental samples by flame atomic absorption spectrometry

A new and simple column-solid-phase extraction method has been developed to separate and preconcentrate trace cobalt in water and soil prior to its determination by flame atomic absorption spectrometry (FAAS). Different factors such as pH of sample solution, sample volume, amount of resin, flow rate of aqueous solution, volume and concentration of eluent, and matrix effects for preconcentration were optimized. Under optimized experimentally established conditions, an analytical detection limit of 0.44?µg?L^?1, precision (RSD) of 1.9%, enrichment factor of 200, and capacity of resin of 82?mg?g^?1 were obtained. The method was applied for cobalt determination by FAAS in tap water, natural drinking water, soil, and roadside dust samples. The accuracy of the method is confirmed by analysing standard reference material (Montana Soil, SRM 2711).     

Cloud point extraction for the determination of cadmium and lead employing sequential multi-element flame atomic absorption spectrometry

A cloud point extraction procedure for pre-concentration and determination of cadmium and lead in drinking water using sequential multi-element flame atomic absorption spectrometry is described. 4-(2-thiazolylazo)-orcinol (TAO) has been used as complexing agent and the micellar phase was obtained using the non-ionic surfactant octylphenoxypolyethoxyethanol (Triton X-114) and centrifugation. The conditions for reaction and extraction (surfactant concentration, reagent concentration, effect of incubation time, etc) were studied and the analytical characteristics of the method were determined. The method allows the determination of cadmium and lead with quantification limits of 0.30?µg?L^?1 and 2.6?µg?L^?1, respectively. A precision expressed as relative standard deviation (RSD, n?=?10) of 2.3% and 2.6% has been obtained for cadmium concentrations of 10?µg?L^?1 and 30?µg?L^?1, respectively, and RSD of 1.3% and 1.7% for lead concentrations of 10?µg?L^?1 and 30?µg?L^?1, respectively. The accuracy was confirmed by analysis of a natural water certified reference material. The method has been applied for the determination of cadmium and lead in drinking water samples collected in the cities of Ilhéus and Itabuna, Brazil. Recovery tests have also been performed for some samples, and results varied from 96 to 105% for cadmium and 97 to 106% for lead. The cadmium and lead concentrations found in these samples were always lower than the permissible maximum levels stipulated by World Health Organization and the Brazilian Government.     

Ionic liquid magnetic bar microextraction and HPLC determination of carbamate pesticides in real water samples

We have developed a simple method for the microextraction of the carbamate pesticides carbofuran, pirimicarb, and carbaryl. It is termed ionic liquid magnetic bar microextraction (ILMB-ME) and based on an ionic liquid deposited on a magnetic stirrer bar placed in a sealed short PCR tube into which microholes where pinned. When placed in a vial containing the aqueous sample solution, the ILMB tumbles freely in the aqueous solution and the carbamates are extracted into the ionic liquid phase which then was determined by HPLC. The enrichment factors for carbofuran, pirimicarb, and carbaryl are 107, 94, 95, respectively. The limits of detection, calculated as three times the signal-to-noise ratio (S/N), are 1.4?μg?L^?1 for carbofuran, 3.4?μg?L^?1 for pirimicarb, and 1.7?μg?L^?1 for carbaryl. The repeatability, carried out by extracting water samples spiked with carbamate levels of 200?μg?L^?1, yielded relative standard deviations between 2.9 and 6.0?%, (for n?=?5). The recoveries of all the three fungicides from tap, lake and rain water samples at spiking levels of 5 and 50?μg?L^?1 are in the range from 86 to 98?%, and from 80 to 96?%, respectively. We conclude that this is a simple, practical and efficient method for the determination of fungicide residues in real water samples.

Dispersive liquid–liquid microextraction and spectrophotometric determination of cobalt in water samples

A new simple and rapid dispersive liquid–liquid microextraction has been applied to preconcentrate trace levels of cobalt as a prior step to its determination by spectrophotometric detection. In this method a small amount of chloroform as the extraction solvent was dissolved in pure ethanol as the disperser solvent, then the binary solution was rapidly injected by a syringe into the water sample containing cobalt ions complexed by 1-(2-pyridylazo)-2-naphthol (PAN). This forms a cloudy solution. The cloudy state was the result of chloroform fine droplets formation, which has been dispersed in bulk aqueous sample. Therefore, Co-PAN complex was extracted into the fine chloroform droplets. After centrifugation (2 min at 5000 rpm) these droplets were sedimented at the bottom of conical test tube (about 100 µL) and then the whole of complex enriched extracted phase was determined by a spectrophotometer at 577 nm. Complex formation and extraction are usually affected by some parameters, such as the types and volumes of extraction solvent and disperser solvent, salt effect, pH and the concentration of chelating agent, which have been optimised for the presented method. Under optimum conditions, the enhancement factor (as the ratio of slope of preconcentrated sample to that obtained without preconcentration) of 125 was obtained from 50 mL of water sample, and the limit of detection (LOD) of the method was 0.5 µg L^?1and the relative standard deviation (RSD, n = 5) for 50 µg L^?1 of cobalt was 2.5%. The method was applied to the determination of cobalt in tap and river water samples.     

O. Carboxyphenylhydrazoethylacetoacetate as an Analytical Reagent for the Determination of Cu(II) and Co(II) in Complex Materials

An extraction‐spectrophotometric method for the determination of trace amounts of copper and cobalt based on their extraction into n‐pentanol with 0. carboxyphenylhydrazoethylacetoacetate (O.CPHEAA) was per formed. Copper was extracted from pH 6.0 – 8.0 and ionic strength 0.5 M – KCl. The maximum absorption of the extracted Cu(II) ‐ O.CPHEAA complex (1:1 & 1:2 species) occurs at 415 nm. The proposed method succeeded in as saying a concentration of 3–63 μg per 10 mL of n‐pentanol (? = 1.25 × 10⁴L mol^?1 cm^?1). The method failed to ex tract cobalt ion into various organic sol vents over a pH range of 2–11. The suggested method is highly selective and sensitive according to a wide scheme of interference studied. Copper in some plant samples was accurately estimated using the suggested method. The obtained results and the results of the AAS method were consistent. The reproducibility test shows a relative standard deviation of 1%. Sandell sensitivity for A = 0.001 is 5 × 10^?3 μg cm^?2.     

Development and validation of a SPE-GC-MS method for the determination of pesticides in surface water

A method for analysis of 20 commonly used pesticides in surface water based on solid-phase extraction and gas chromatography-mass spectrometry was proposed. During method development the key parameters that can affect SPE extraction and determination such as selection of efficient SPE sorbent, pH of water sample, type and volume of elution solvent, breakthrough volume and matrix effects were investigated. The method was validated using spring water spiked with appropriate concentration of pesticides. The obtained correlation coefficients were in range 0.9972–1.000, limits of detection (LOD) were 0.001–0.5?µg?L^?1 and the limits of quantification (LOQ) were 0.005–1?µg?L^?1 depending on a pesticide. Much higher LOD (20?µg?L^?1) and LOQ (50?µg?L^?1) values were obtained for bentazone. The influence of matrix was assessed using real water samples spiked with appropriate concentration of pesticide standards solution. Both signal enhancement and suppression were observed, depending on a pesticide, therefore standard addition method was used for pesticides determination. The developed method was applied on real water samples taken in close vicinity of agricultural fields. Many of the targeted pesticides were found in the samples and the results are presented in this article.     

Coacervative extraction of phthalates from water and their determination by high performance liquid chromatography

A simple, rapid and low cost method for determination of phthalic acid esters (PAEs) including Dimethyl phthalate (DMP), Diethyl phthalate (DEP), Di-n-butyl phthalate (DBP) and Butylbenzyl phthalate (BBP) in water samples was investigated. The method is based on the extraction of PAEs with coacervate made up of decanoic acid reverse micelles and the subsequent determination by HPLC-UV. Effect of parameters such as concentration of tetrahydrofuran (THF) (2?C40% v/v) and decanoic acid (20?C400 mg in 40 ml total volume), ionic strength (0.0?C0.1 M NaCl), pH (1?C4) and stirring time (2?C60 min) on recoveries (Rs) and enrichment factors (EFs) were investigated and optimized. The optimum condition for extraction was the stirring of 36 ml of water sample with 4 ml of THF containing 100 mg of decanoic acid for 10 min and its centrifugation (10 min, 3500 rpm). Recoveries and enrichment factors of PAEs mainly depended on the amount of decanoic acid and THF making up the coacervate and were not affected by ionic strength of the sample solution (up to 0.1 M of NaCl), pH (1?C4), and stirring time (2?C60 min). Recoveries, enrichment factors, LODs and relative standard deviations (RSD%) for PAEs were between 87?C94%, 187?C202, 0.22?C0.30 ??g l^?1 and 2?C5%, respectively. This method was applied to determine PAEs in tap water, river water, and sea water samples. No PAEs were found in tap water. The amount of DMP and DEP in the Babolrood River was 0.87 and 0.67 ??g l^?1, while in the Caspian Sea was 0.49 and 0.52 ??g l^?1, respectively.     

Temperature-controlled ionic liquid dispersive liquid phase microextraction combined with ultra-high-pressure liquid chromatography for the rapid determination of triclosan, triclocarban and methyl-triclosan in aqueous samples

As extraction solvents, ionic liquids have green characteristics. In this study, an environmentally benign analytical method termed temperature-controlled ionic liquid dispersive liquid phase microextraction (TIL-DLME) combined with ultra-highpressure liquid chromatography (UHPLC)-tunable ultraviolet detection (TUV) was developed for the pre-concentration and determination of triclosan (TCS), triclocarban (TCC) and methyl-triclosan (M-TCS) in water samples. Significant parameters that may affect extraction efficiencies were examined and optimized, including the types and amount of ionic liquids, volume of the diluent, heating temperature, cooling time, salt effect and pH value. Under the optimum conditions, linearity of the method was observed in the ranges of 0.0100–100 μg L^?1 for TCS and M-TCS, and 0.00500–50.0 μg L^?1 for TCC with correlation coefficients (r ²) > 0.9903. The limits of detection (LODs) ranged from 1.15 to 5.33 ng L^?1. TCS in domestic water and TCC in reclaimed water were detected at the concentrations of 1.01 and 0.126 μg L^?1, respectively. The spiked recoveries of the three target compounds in reclaimed water, irrigating water, waste water and domestic water samples were obtained in the ranges of 68.4%–71.9%, 61.6%–87.8%, 58.9%–74.9% and 64.9%–92.4%, respectively. Compared with the previous dispersive liquid-liquid microextraction method (DLLME) about the determination of TCS, TCC and M-TCS, this method is not only more environmentally friendly but also more sensitive.     

Syringe-to-syringe-dispersive liquid–phase microextraction combined with flame atomic absorption spectrometry for pre-concentration and determination of cobalt with the aid of experimental design

A rapid and selective technique has been proposed for the extraction, pre-concentration and determination of trace amounts of cobalt in water and pharmaceutical samples by syringe-to-syringe-dispersive liquid–phase microextraction (SS-DLPME) combined with flame atomic absorption spectrometry (FAAS). In the developed method, 1-nitroso-2-naphthol was used as a selective complexing agent and 1-octanol was selected as the extraction solvent. Factors such as pH of the sample solution, concentration of the complexing agent, volume of the extraction solvent, number of injections and centrifugation time affecting the extraction efficiency were screened using a Plackett–Burman design (PBD) and optimised using a Box–Behnken design (BBD). Under optimum conditions, a dynamic linear range of 2.5–650 μg L^?1 with the coefficient of determination r² = 0.997 was obtained. The resultant limit of detection (LOD) was 0.68 μg L^?1, whereas the enrichment factor (EF), intraday precision and inter-day precision were 281, 1.43% and 1.93%, respectively. This method was used successfully for pre-concentration and determination of the analyte in environmental water and drug samples.     

Simultaneous Determination of Cadmium,Lead, Copper,and Thallium in Highly Saline Samples by Anodic Stripping Voltammetry (ASV) Using Mercury‐Film and Bismuth‐Film Electrodes

This paper describes a comparative study of the simultaneous determination of Cd(II), Pb(II), Tl(I), and Cu(II) in highly saline samples (seawater, hydrothermal fluids, and dialysis concentrates) by ASV using the mercury‐film electrode (MFE) and the bismuth‐film electrode (BiFE) as working electrodes. The features of MFE and BiFE as working electrodes for the single‐run ASV determinations are shown and their performances are compared with that of HMDE under similar conditions. It was observed that the stripping peak of Tl(I) was well separated from Cd(II) and Pb(II) peaks in all the studied saline samples when MFE was used. Because of the severe overlapping of Bi(III) and Cu(II) stripping peaks in the ASV using BiFE, as well as the overlapping of Pb(II) and Tl(I) stripping peaks in the ASV using HMDE, the simultaneous determination of these metals was not possible in highly saline medium using these both working electrodes. The detection limits calculated for the metals using MFE and BiFE (deposition time of 60 s) were between 0.043 and 0.070 μg L^?1 for Cd(II), between 0.060 and 0.10 μg L^?1 for Pb(II) and between 0.70 and 8.12 μg L^?1 for Tl(I) in the saline samples studied. The detection limits calculated for Cu(II) using the MFE were 0.15 and 0.50 μg L^?1 in seawater/hydrothermal fluid and dialysis concentrate samples, respectively. The methods were applied to the simultaneous determination of Cd(II), Pb(II), Tl(I), and Cu(II) in samples of seawater, hydrothermal fluids and dialysis concentrates.     

Ultra-trace arsenic and mercury speciation and determination in blood samples by ionic liquid-based dispersive liquid-liquid microextraction combined with flow injection-hydride generation/cold vapor atomic absorption spectroscopy

A simple, fast, and sensitive method for speciation and determination of As (III, V) and Hg (II, R) in human blood samples based on ionic liquid-dispersive liquid-liquid microextraction (IL-DLLME) and flow injection hydride generation/cold vapor atomic absorption spectrometry (FI-HG/CV-AAS) has been developed. Tetraethylthiuram disulfide, mixed ionic liquids (hydrophobic and hydrophilic ILs) and acetone were used in the DLLME step as the chelating agent, extraction and dispersive solvents, respectively. Using a microwave assisted-UV system, organic mercury (R-Hg) was converted to Hg(II) and total mercury amount was measured in blood samples by the presented method. Total arsenic content was determined by reducing As(V) to As(III) with potassium iodide and ascorbic acid in a hydrochloric acid solution. Finally, As(V) and R-Hg were determined by mathematically subtracting the As(III) and Hg(II) content from the total arsenic and mercury, respectively. Under optimum conditions, linear range and detection limit (3σ) of 0.1–5.0 µg L^?1 and 0.02 µg L^?1 for As(III) and 0.15–8.50 µg L^?1 and 0.03 µg L^?1 for Hg(II) were achieved, respectively, at low RSD values of < 4% (N = 10). The developed method was successfully applied to determine the ultra-trace amounts of arsenic and mercury species in blood samples; the validation of the method was performed using standard reference materials.