Ligandless-dispersive liquid-liquid microextraction of trace amount of copper ions

In the present work, a new ligandless-dispersive liquid-liquid microextraction (LL-DLLME) method has been developed for preconcentration trace amounts of copper as a prior step to its determination by flame atomic absorption spectrometry. In the proposed approach 1,2-dicholorobenzene and ethanol were used as extraction and dispersive solvents, respectively. Some factors influencing on the extraction efficiency of copper and its subsequent determination were studied and optimized, such as the extraction and dispersive solvent type and volume, pH of sample solution, extraction time and salting out effect. Under the optimal conditions, the calibration curve was linear in the range of 1.0 ng mL⁻¹-0.6 μg mL⁻¹ of copper with R² = 0.9985. Detection limit was 0.5 ng mL⁻¹ in original solution (3S_b/m) and the relative standard deviation for seven replicate determination of 0.2 μg mL⁻¹ copper was ±1.4%. The proposed method has been applied for determination of copper in standard and water samples with satisfactory results.     

Ligandless dispersive liquid-liquid microextraction for the separation of trace amounts of silver ions in water samples and flame atomic absorption spectrometry determination

In this article, a new ligandless dispersive liquid-liquid microextraction method has been developed for preconcentration of trace quantities of silver as a prior step to its determination by flame atomic absorption spectrometry. In the proposed approach, carbon tetrachloride and ethanol were used as extraction and dispersive solvents. Several factors that may be affected on the extraction process, like, extraction solvent, disperser solvent, the volume of extraction and disperser solvent, pH of the aqueous solution and extraction time were optimized. Under the optimal conditions, the calibration curve was linear in the range of 5.0 ng mL⁻¹ to 2.0 μg mL⁻¹ of silver with R² = 0.9995 (n = 9) and detection limit based on three times the standard deviation of the blank (3S_b) was 1.2 ng mL⁻¹ in original solution. The relative standard deviation for eight replicate determination of 0.5 μg mL⁻¹ silver was ±1.5%. The high efficiency of dispersive liquid-liquid microextraction to carry out the determination of silver in complex matrices was demonstrated. The proposed method has been applied for determination of trace amount of silver in standard and water samples with satisfactory results.     

An on-line preconcentration/separation system for the determination of bismuth in environmental samples by FAAS

An on-line preconcentration procedure for the determination of bismuth by flame atomic absorption spectrometry (FAAS) has been described. Lewatit TP-207 chelating resin, including iminodiacetate group, packed in a minicolumn was used as adsorbent material. Bi(III) was sorbed on the chelating resin, from which it could be eluted with 3 mol L⁻¹ HNO₃ and then introduced directly to the nebulizer-burner system of FAAS. Best preconcentration conditions were established by testing different resin quantities, acidity of sample, types of eluent, sample and eluent solution volumes, adsorption and elution flow rates, and effect of interfering ions. The detection limit of the method was 2.75 μg L⁻¹ while the relative standard deviation was 3.0% for 0.4 μg mL⁻¹ Bi(III) concentration. The developed method has been applied successfully to the determination of bismuth in pharmaceutical cream, standard reference materials and various natural water samples with satisfactory results.     

Flame atomic absorption spectrometry for the determination of trace amount of rhodium after separation and preconcentration onto modified multiwalled carbon nanotubes as a new solid sorbent

The present article reports on the application of modified multiwalled carbon nanotubes (MMWCNTs) as a new, easily prepared and stable solid sorbent for the preconcentration of trace rhodium ion in aqueous solution. Rhodium ions were complexed with 1-(2-pyridylazo)-2-naphthol (PAN) in the pH range of 3.2-4.7 and then the formed Rh-PAN complex was adsorbed on the oxidized MWCNTs. The adsorbed complex was eluted from MWCNTs sorbent with 5.0 mL of N,N-dimethylformamide (DMF). The rhodium in eluted solution was determined by flame atomic absorption spectrometry (FAAS). Linear range for the determination of rhodium was maintained between 0.16 ng mL⁻¹ and 25.0 μg mL⁻¹ in initial solution. Relative standard deviation for the 10 replicated determination of 4.0 μg mL⁻¹ of rhodium was ±0.97%. Detection limit was 0.010 ng mL⁻¹ in initial solution (3S_bl, n = 10) and preconcentration factor was 120. Sensitivity for 1% absorbance of rhodium (III) was 0.112 μg mL⁻¹. The sorption capacity of oxidized MWCNTs for Rh (III) was 6.6 mg g⁻¹. The effects of the experimental parameters, including the sample pH, flow rates of sample and eluent solution, eluent type, breakthrough volume and interference ions were studied for the preconcentration of Rh³⁺. The proposed method was successfully applied to the extraction and determination of rhodium in different samples.     

Simultaneous cloud point extraction and spectrophotometric determination of carmoisine and brilliant blue FCF in food samples

A novel simultaneous cloud point extraction method for the determination of carmoisine and brilliant blue FCF by spectrophotometry has been developed. The method is based on the cloud point extraction of carmoisine and brilliant blue FCF from aqueous solution using Triton X-100, diluting the extracted surfactant rich phase with water and measuring the absorbance at 522 and 640 nm for carmoisine and brilliant blue FCF, respectively. The effects of different parameters such as pH, concentration of surfactant and temperature on the cloud point extraction of both dyes were investigated and optimum conditions were established. Linear calibration curves were obtained in the range of 0.02-3.50 μg mL⁻¹ for carmoisine and 0.05-3.50 μg mL⁻¹ for brilliant blue FCF under optimum conditions. Detection limit based on three times the standard deviation of the blank (3S_b) was 0.017 and 0.016 μg mL⁻¹ (n = 10) for carmoisine and brilliant blue FCF, respectively. The relative standard deviation (RSD) for 0.1 μg mL⁻¹ was 4.14 and 3.30% (n = 10), for carmoisine and brilliant blue FCF, respectively. The method was applied to the simultaneous determination of the dyes in different food samples.     

Ion chromatography for rapid and sensitive determination of fluoride in milk after headspace single-drop microextraction with in situ generation of volatile hydrogen fluoride

In this article, we report a new method that involves headspace single-drop microextraction and ion chromatography for the preconcentration and determination of fluoride. The method lies in the in situ hydrogen fluoride generation and subsequent sequestration into an alkaline microdrop (15 μL) exposed to the headspace above the stirred aqueous sample. The NaF formed in the drop was then determined by ion chromatography. The influences of some crucial single-drop microextraction parameters such as the extraction temperature, extraction time, sample stirring speed, sulphuric acid concentration and ionic strength of the sample, on extraction efficiency were investigated. In the optimal condition, an enrichment factor of 97 was achieved in 15 min. The calibration working range was from 10 μg L⁻¹ to 2000 μg L⁻¹ (R² = 0.998), and the limit of detection (signal to noise ratio of 3) was 3.8 μg L⁻¹ of fluoride. Finally, the proposed method was successfully applied to the determination of fluoride in different milk samples. The recoveries of fluoride (at spiked concentrations of 200 μg L⁻¹ and 600 μg L⁻¹ into milk) in real samples ranged from 96.9% to 107.7%. Intra-day precision (N = 3) in terms of peak area, expressed as relative standard deviation, was found to be within the range of 0.24-1.02%.     

Flow injection chemiluminescence determination of nitrofurazone in pharmaceutical preparations and biological fluids based on oxidation by singlet oxygen generated in N-bromosuccinimide-hydrogen peroxide reaction

A simple flow injection chemiluminescence (FI-CL) method was proposed for the determination of nitrofurazone. Strong CL signal was generated during the reaction of nitrofurazone with H₂O₂ and N-bromosuccinimide (NBS) in alkaline condition. The CL signal was proportional to the nitrofurazone concentration in the range 1.0 × 10⁻⁷ to 1.0 × 10⁻⁵ g mL⁻¹. The detection limit was 2 × 10⁻⁸ g mL⁻¹ nitrofurazone and the relative standard deviation was less than 4% (6.0 × 10⁻⁶ g mL⁻¹ nitrofurazone, n = 11). The proposed method was successfully applied to the determination of nitrofurazone in compound furacillin nasal drops, human plasma and urine samples. The CL reaction mechanism was also discussed briefly. Singlet oxygen generated in the reaction between H₂O₂ and NBS was suggested to be participated in the CL reaction.     

A reversed-phase high performance liquid chromatography coupled with resonance Rayleigh scattering detection for the determination of four tetracycline antibiotics

A new reversed-phase high performance liquid chromatography with resonance Rayleigh scattering detection (HPLC-RRS) was developed for simultaneous separation and determination of four tetracycline antibiotics (TCs). A good chromatographic separation among the compounds was achieved using a Synergi Fusion-RP column (150 mm × 4.6 mm; 4 μm) and a mobile phase consisting of methanol-acetonitrile-oxalic acid (5 mM) at the flow rate of 0.8 mL min⁻¹. Column temperature was 30 °C. The RRS signal was detected at λ_ex = λ_em = 370 nm. The recoveries of sample added standard ranged from 95.3% to 103.5%, and the relative standard deviation was below 2.79%. A detection limit of 2.12-5.12 μg mL⁻¹ was reached and a linear range was found between peak height and concentration in the range of 10.36-518.0 μg mL⁻¹ for oxytetracycline (OTC), 12.11-605.5 μg mL⁻¹ for tetracycline (TC), 11.79-589.5 μg mL⁻¹ for chlortetracycline (CTC) and 10.32-516.0 μg mL⁻¹ for doxycycline (DC). The linear regression coefficients were all above 0.999. The method has been applied successfully to the determination of OTC, TC, CTC, DC in pharmaceutical formulations and in honey. The method was simple, rapid and showed a better linear relation and high repeatability.     

Flow injection chemiluminescence determination of naproxen based on KMnO4-Na2SO3 reaction in neutral aqueous medium

A simple, rapid and sensitive flow injection chemiluminescence (CL) method is described for the determination of naproxen. It was found that strong CL signal was generated when naproxen was mixed with KMnO₄ and Na₂SO₃ in neutral aqueous medium. Under the optimum experimental conditions, the CL intensity was linearly related to the concentration of naproxen from 4.0 × 10⁻⁹ to 1.0 × 10⁻⁶ g mL⁻¹ (r = 0.9993). The detection limit was 2 × 10⁻⁹ g mL⁻¹ naproxen, the relative standard deviation for 1.0 × 10⁻⁷ g mL⁻¹ naproxen solution was 1.5% (n = 11) and the sampling frequency was 120 h⁻¹. The method was applied to the determination of naproxen in pharmaceutical preparation with satisfactory results. The mechanism of CL reaction was discussed briefly.     

Simultaneous chemiluminescence determination of promazine and fluphenazine using support vector regression

In this work, chemiluminescence (CL) behaviors of two selected phenothiazines, namely promazine and fluphenazine hydrochloride, were investigated for their simultaneous determination using oxidation of Ru(bipy)₃²⁺ by Ce⁴⁺ ions in acidic media. This method is based on the kinetic distinction of the CL reactions of fluphenazine and promazine with Ru(bipy)₃²⁺ and Ce⁴⁺ system in a sulfuric acid medium. Least square support vector regression models were constructed for relating concentrations of both compounds to their CL profiles. The parameters of the model consisting of σ² and γ were optimized using all possible combinations of σ² and γ to select the model with the minimum root mean square cross validation. Under optimized conditions, the univariate calibration curve was linear over the concentration ranges of 0.4-30.0 μg mL⁻¹ and 0.07-5.0 μg mL⁻¹ with detection limits of 0.1 μg mL⁻¹ and 0.04 μg mL⁻¹ for promazine and fluphenazine, respectively. The influence of potential interfering substances on the determination of promazine and fluphenazine were studied. The proposed method was used for simultaneous determination of both compounds in synthetic mixtures and in spiked human plasma.     

Simultaneous determination of salbutamol sulphate, bromhexine hydrochloride and etofylline in pharmaceutical formulations with the use of four rapid derivative spectrophotometric methods

Four simple, rapid, accurate, precise, reliable and economical spectrophotometric methods have been proposed for simultaneous determination of salbutamol sulphate (SS), bromhexine hydrochloride (BH) and etofylline (ET) in pure and commercial formulations without any prior separation or purification. They were first derivative zero crossing spectrophotometry (method 1), simultaneous equation method (method 2), derivative ratio spectra zero crossing method (method 3) and double divisor ratio spectra derivative method (method 4). The ranges for SS, BH and ET were found to be 1-35 μg mL⁻¹, 4-40 μg mL⁻¹ and 5-80 μg mL⁻¹. For methods 1 and 2, the values of limit of detection (LOD) were 0.2314 μg mL⁻¹, 0.4865 μg mL⁻¹ and 0.2766 μg mL⁻¹ and the values of limit of quantitation (LOQ) were 0.7712 μg mL⁻¹, 1.6217 μg mL⁻¹ and 0.9221 μg mL⁻¹ for SS, BH and ET, respectively. For method 3, LOD values were 0.3297 μg mL⁻¹, 0.2784 μg mL⁻¹ and 0.7906 μg mL⁻¹ and LOQ values were 0.9325 μg mL⁻¹, 0.9282 μg mL⁻¹ and 2.6352 μg mL⁻¹ for SS, BH and ET, respectively. For method 4, LOD values were 0.3161 μg mL⁻¹, 0.2495 μg mL⁻¹ and 0.2064 μg mL⁻¹ and LOQ values were 0.9869 μg mL⁻¹, 0.8317 μg mL⁻¹ and 0.6879 μg mL⁻¹ for SS, BH and ET. The precision values were less then 2% R.S.D. for all four methods. The common excipients and additives did not interfere in their determinations. The results obtained by the proposed methods have been statistically compared by means of Student t-test and by the variance ratio F-test.     

Determination of cadmium by flame atomic absorption spectrometry after preconcentration on naphthalene-methyltrioctylammonium chloride adsorbent as tetraiodocadmate (II) ions

A sensitive and simple solid-phase preconcentration procedure for enrichment of cadmium prior to analysis by flame atomic absorption spectrometry (FAAS) is described. The method is based on the adsorption of cadmium as CdI₄²⁻ on naphthalene-methyltrioctylammonium chloride adsorbent, elution by nitric acid and subsequent determination by FAAS. The effect of pH, iodide concentration, sample flow rate, volume of the sample and diverse ions on the recovery of the analyte was investigated and optimum conditions were established. A preconcentration factor of 40 was achieved using the optimum conditions. The calibration graph was linear in the range 1-100 ng ml⁻¹ cadmium in the initial solution. The detection limit based on the 3S_b criterion was 0.6 ng ml⁻¹ and the relative standard deviations (RSD) were 3.9 and 1.05% for 5 and 40 ng ml⁻¹, respectively (n=8). The method was successfully applied to the determination of cadmium added to river, tap and Persian Gulf water samples.     

Preconcentration and spectrophotometric determination of low concentrations of malachite green and leuco-malachite green in water samples by high performance solid phase extraction using maghemite nanoparticles

A novel and sensitive extraction procedure using maghemite nanoparticles (γ-Fe₂O₃) modified with sodium dodecyl sulfate (SDS), as an efficient solid phase, was developed for removal, preconcentration and spectrophotometric determination of trace amounts of malachite green (MG) and leuco-malachite green (LMG). Combination of nanoparticle adsorption and easily magnetic separation was used to extraction and desorption of MG and LMG. The adsorption capacity was evaluated using both the Langmuir and Freundlich adsorption isotherm models. Maghemite nanoparticles were prepared by co-precipitation method and their surfaces were modified by SDS. The size and properties of the produced maghemite nanoparticles was determined by X-ray diffraction (XRD) analysis, scanning electron microscopy (SEM) and BET analysis. MG and LMG became adsorbed at pH 3.0. LMG was oxidized to MG by adsorption on maghemite nanoparticles. The adsorbed MG was then desorbed and determined spectrophotometrically. The calibration graph was linear in the range 0.50-250.00 ng mL⁻¹ of MG and LMG with a correlation coefficient of 0.9991. The detection limit of the method for determination of MG was 0.28 ng mL⁻¹ and the relative standard deviation (R.S.D.) for 10.00 and 50.00 ng mL⁻¹ of malachite green was 1.60% (n = 3) and 0.86% (n = 5), respectively. A preconcentration factor of 50 was achieved in this method. The Langmuir adsorption capacity (q_max) was found to be 227.3 mg g⁻¹ of the adsorbent. The method was applied to the determination of MG in fish farming water samples.     

Investigation on enhanced chemiluminescence reaction systems with bis(hydrogenperiodato) argentate(III) complex anion for fluoroquinolones synthetic antibiotics

A novel chemiluminescence (CL) reaction system with bis(hydrogenperiodato) argentate(III) complex anion (Ag(III) complex, [Ag(HIO₆)₂]⁵⁻), for the first time, is developed for the determination of lomefloxacin (LMFX), enrofloxacin (ENLX) and pefloxacin (PFLX). The possible CL emission mechanism was discussed by comparing the fluorescence emission with CL spectra. The CL conditions of [Ag(HIO₆)₂]⁵⁻-H₂SO₄-LMFX/ENLX/PFLX systems were investigated and optimized. Under the optimized experimental conditions, the CL intensity is proportional to the concentration of the drugs in the range 0.2994-36.80 × 10⁻⁷ g mL⁻¹ for LMFX, 4.00-30.0 × 10⁻⁷ g mL⁻¹ for ENLX and 1.54-27.64 × 10⁻⁷ g mL⁻¹ for PFLX. The limit of detection (s/n = 3) was 9.1 × 10⁻⁹ g mL⁻¹ for LMFX, 3.1 × 10⁻⁹ g mL⁻¹ for ENLX and 4.4 × 10⁻⁹ g mL⁻¹ for PFLX. The recovery of LMFX, ENLX and PELX from the spiked pharmaceutical preparations was in the range of 92.3-105% with the RSDs of 0.5-2.7%. For urine, serum and milk samples the recoveries of the three drugs were in the range of 85.1-107% for LMFX with the RSDs of 2.3-3.4%. 80.2-112% for ENLX with the RSDs of 1.4-2.8%, and 87.8-114% for PFLX with the RSDs of 1.6-2.7%. The proposed method was applied successfully to the determination of these compounds in real samples.     

Mesoporous titanium dioxide as a novel solid-phase extraction material for flow injection micro-column preconcentration on-line coupled with ICP-OES determination of trace metals in environmental samples

Mesoporous titanium dioxide as a novel solid-phase extraction material for flow injection micro-column preconcentration on-line coupled with ICP-OES determination of trace metals (Co, Cd, Cr, Cu, Mn, Ni, V, Ce, Dy, Eu, La and Yb) in environmental samples was described. Possessing a high adsorption capacity towards the metal ions, mesoporous titanium dioxide has found to be of great potential as an adsorbent for the preconcentration of trace metal ions in samples with complicated matrix. The experimental parameters including pH, sample flow rate, volume, elution and interfering ions on the recovery of the target analytes were investigated, and the optimal experimental conditions were established. Under the optimized operating conditions, a preconcentration time of 90 s and elution time of 18 s with enrichment factor of 10 and sampling frequency of 20 h⁻¹ were obtained. The detection limits of this method for the target elements were between 0.03 and 0.36 μg L⁻¹, and the relative standard deviations (R.S.D.s) were found to be less than 6.0% (n =7, c =5 ng mL⁻¹). The proposed method was validated using a certified reference material, and has been successfully applied for the determination of the afore mentioned trace metals in natural water samples and coal fly ash with satisfactory results.     

Silica gel-polyethylene glycol as a new adsorbent for solid phase extraction of cobalt and nickel and determination by flame atomic absorption spectrometry

In this paper a novel solid phase extraction method to determine Co(II) and Ni(II) using silica gel-polyethylene glycol (Silica-PEG) as a new adsorbent is described. The method is based on the adsorption of cobalt and nickel ions in alkaline media on polyethylene glycol-silica gel in a mini-column, elution with nitric acid and determination by flame atomic absorption spectrometry. The adsorption conditions such as NaOH concentration, sample volume and amount of adsorbent were optimized in order to achieve highest sensitivity. The calibration graph was linear in the range of 0.5-200.0 ng mL⁻¹ for Co(II) and 2.0-100.0 ng mL⁻¹ for Ni(II) in the initial solution. The limit of detection based on 3S_b was 0.37 ng mL⁻¹ for Co(II) and 0.71 ng mL⁻¹ for Ni(II). The relative standard deviations (R.S.D.) for ten replicate measurements of 40 ng mL⁻¹ of Co(II), and Ni(II) were 3.24 and 3.13%, respectively. The method was applied to determine Co(II) and Ni(II) in black tea, rice flour, sesame seeds, tap water and river water samples.     

Determination of beta-lactam antibiotics in milk using micro-flow chemiluminescence system with on-line solid phase extraction

In this paper, a chemiluminescence (CL) micro-flow system combined with on-line solid phase extraction (SPE) is presented for determination of β-lactam antibiotics (penicillin, cefradine, cefadroxil, cefalexin) in milk. It is based on the enhancement effect of β-lactam antibiotics on the luminol-K₃Fe(CN)₆ CL system. The micro-flow system was fabricated from two polymethyl methacrylate (PMMA) plates (50 mm × 40 mm × 5 mm) with the microchannels of 200 μm wide and 150 μm deep. C₁₈-modified silica gel was packed into the microchannel (length: 10 mm; width: 1 mm; depth: 500 μm) to serve as SPE device. Extraction and preconcentration of the analytes were carried out using on-line SPE micro-flow system and the selectivity of CL detection was improved. The detection limits were 0.5 μg mL⁻¹ of penicillin, 0.04 μg mL⁻¹ of cefradine, 0.08 μg mL⁻¹ of cefadroxil and 0.1 μg mL⁻¹ of cefalexin. The proposed method was also applied to analyze the β-lactam antibiotics in milk. Experimental results were in good agreement with those obtained by high performance liquid chromatography (HPLC) method with UV detection.     

A novel application of immobilization on membranes for the separation and spectrofluorimetric quantification of amiloride and furosemide in pharmaceutical samples

A new, simple and highly sensitive method for spectrofluorimetric determination of amiloride (AMI) and furosemide (FUR) in pharmaceuticals is presented. The proposed method is based on the separation of AMI from FUR by solid-phase extraction using a nylon membrane, followed by spectrofluorimetric determination of both drugs, on the solid surface and the filtered aqueous solution, respectively. AMI shows low native fluorescence, but its separation-preconcentration by immobilization (solid-phase extraction) on nylon membrane surface provides a considerable enhancement in fluorescence intensity. The fluorescence determination is carried out at λ_ex = 237, λ_em = 415 nm for FUR; and λ_ex = 365, λ_em = 406 nm for AMI. The calibration graphs are linear in the range 3.20 × 10⁻⁴ to 0.8 μg mL⁻¹and 1.33 × 10⁻³ to 4.0 μg mL⁻¹, for AMI and FUR, respectively, with a detection limit of 9.62 × 10⁻⁵ and 4.01 × 10⁻⁴ μg mL⁻¹ (S/N = 3). The commonly found excipients in commercial pharmaceutical formulations do not interfere. The developed method is successfully applied to the determination of both drugs in pharmaceutical formulations.     

Development of a flow system for the determination of low concentrations of silver using Moringa oleifera seeds as biosorbent and flame atomic absorption spectrometry

In this study a method for the determination of low concentrations of silver in waters using solid-phase extraction with a flow injection analysis system and detection by flame atomic absorption spectrometry (FAAS) was developed. Moringa oleifera seeds were used as a biosorbent material. Chemical and flow variables of the on-line preconcentration system such as sample pH and flow rate, preconcentration time, eluent concentration and sorbent mass were studied. The optimum preconcentration conditions were obtained using sample pH in the range of 6.0-8.0, preconcentration time of 4 min at a flow rate of 3.5 mL min^− 1, 0.5 mol L^− 1 HNO₃ eluent at a flow rate of 4.5 mL min^− 1 and 35 mg of sorbent mass. With the optimized conditions, the preconcentration factor, precision, detection limit and sample throughput were estimated as 35 (for preconcentration of 14 mL sample), 3.8% (5.0 μg L^− 1, n = 7), 0.22 μg L^− 1 and 12 samples per hour, respectively. The developed method was successfully applied to mineral water and tap water, and accuracy was assessed through analysis of a certified reference material for water (APS-1071 NIST) and recovery tests, with recovery ranging from 94 to 101%.     

A chitosan–polypyrrole magnetic nanocomposite as μ-sorbent for isolation of naproxen

An extracting medium based on chitosan–polypyrrole (CS–PPy) magnetic nanocomposite was synthesized by chemical polymerization of pyrrole at the presence of chitosan magnetic nanoparticles (CS-MNPs) for micro-solid phase extraction. In this work, magnetic nanoparticles, the modified CS-MNPs and different types of CS–PPy magnetic nanocomposites were synthesized. Extraction efficiency of the CS–PPy magnetic nanocomposite was compared with the CS-MNPs and Fe₃O₄ nanoparticles for the determination of naproxen in aqueous samples, via quantification by spectrofluorimetry. The scanning electron microscopy images obtained from all the prepared nanocomposites revealed that the CS–PPy magnetic nanocomposite possess more porous structure. Among different synthesized magnetic nanocomposites, CS–PPy magnetic nanocomposite showed a prominent efficiency. Influencing parameters on the morphology of CS–PPy magnetic nanocomposite such as weight ratio of components was also assayed. In addition, effects of different parameters influencing the extraction efficiency of naproxen including desorption solvent, desorption time, amount of sorbent, ionic strength, sample pH and extraction time were investigated and optimized. Under the optimum condition, a linear calibration curve in the range of 0.04–10 μg mL⁻¹ (R² = 0.9996) was obtained. The limits of detection (3S_b) and limits of quantification (10S_b) of the method were 0.015 and 0.04 μg mL⁻¹ (n = 3), respectively. The relative standard deviation for water sample spiked with 0.1 μg mL⁻¹ of naproxen was 3% (n = 5) and the absolute recovery was 92%. The applicability of method was extended to the determination of naproxen in tap water, human urine and plasma samples. The relative recovery percentages for these samples were in the range of 56–99%.