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Saeidi I.,Iranian National Standards Organization | Barfi B.,Semnan University | Payrovi M.,University of Mazandaran | Feizy J.,Testa Quality Control Laboratory | And 3 more authors.
Chinese Journal of Chromatography (Se Pu) | Year: 2015

With polyamide (PA) as an efficient sorbent for solid phase extraction (SPE) of Sudan dyes II, III and Red 7B from saffron and urine, their determination by HPLC was performed. The optimum conditions for SPE were achieved using 7 mL methanol/water (1:9, v/v, pH 7) as the washing solvent and 3 mL tetrahydrofuran for elution. Good clean-up and high (above 90%) recoveries were observed for all the analytes. The optimized mobile phase composition for HPLC analysis of these compounds was methanol-water (70:30, v/v). The SPE parameters, such as the maximum loading capacity and breakthrough volume, were also determined for each analyte. The limits of detection (LODs), limits of quantification (LOQs), linear ranges and recoveries for the analytes were 4.6-6.6 μg/L, 13.0-19.8 μg/L, 13.0-5 000 μg/L (r2 > 0.99) and 92.5% - 113.4%, respectively. The precisions (RSDs) of the overall analytical procedure, estimated by five replicate measurements for Sudan II, III and Red 7B in saffron and urine samples were 2.3%, 1.8% and 3.6%, respectively. The developed method is simple and successful in the application to the determination of Sudan dyes in saffron and urine samples with HPLC coupled with UV detection. Source

Barfi A.,Payam e Noor University of Esfahan | Nazem H.,Payam e Noor University of Esfahan | Saeidi I.,Iranian National Standards Organization | Peyrovi M.,University of Mazandaran | And 2 more authors.
Journal of Pharmaceutical and Biomedical Analysis | Year: 2016

In the present study, an efficient and environmental friendly method (called in-syringe reversed dispersive liquid-liquid microextraction (IS-R-DLLME)) was developed to extract three important components (i.e. para-anisaldehyde, trans-anethole and its isomer estragole) simultaneously in different plant extracts (basil, fennel and tarragon), human plasma and urine samples prior their determination using high-performance liquid chromatography. The importance of choosing these plant extracts as samples is emanating from the dual roles of their bioactive compounds (trans-anethole and estragole), which can alter positively or negatively different cellular processes, and necessity to a simple and efficient method for extraction and sensitive determination of these compounds in the mentioned samples. Under the optimum conditions (including extraction solvent: 120μL of n-octanol; dispersive solvent: 600μL of acetone; collecting solvent: 1000μL of acetone, sample pH 3; with no salt), limits of detection (LODs), linear dynamic ranges (LDRs) and recoveries (R) were 79-81ngmL-1, 0.26-6.9μgmL-1 and 94.1-99.9%, respectively. The obtained results showed that the IS-R-DLLME was a simple, fast and sensitive method with low level consumption of extraction solvent which provides high recovery under the optimum conditions. The present method was applied to investigate the absorption amounts of the mentioned analytes through the determination of the analytes before (in the plant extracts) and after (in the human plasma and urine samples) the consumption which can determine the toxicity levels of the analytes (on the basis of their dosages) in the extracts. © 2016 Elsevier B.V. Source

Saeidi I.,Iranian National Standards Organization | Barfi B.,Semnan University | Asghari A.,Semnan University | Gharahbagh A.A.,Islamic Azad University at Shahrood | And 2 more authors.
Environmental Monitoring and Assessment | Year: 2015

A novel and environmentally friendly ionic-liquid-based hollow-fiber liquid-phase microextraction method combined with a hybrid artificial neural network (ANN)–genetic algorithm (GA) strategy was developed for ferro and ferric ions speciation as model analytes. Different parameters such as type and volume of extraction solvent, amounts of chelating agent, volume and pH of sample, ionic strength, stirring rate, and extraction time were investigated. Much more effective parameters were firstly examined based on one-variable-at-a-time design, and obtained results were used to construct an independent model for each parameter. The models were then applied to achieve the best and minimum numbers of candidate points as inputs for the ANN process. The maximum extraction efficiencies were achieved after 9 min using 22.0 μL of 1-hexyl-3-methylimidazolium hexafluorophosphate ([C6MIM][PF6]) as the acceptor phase and 10 mL of sample at pH = 7.0 containing 64.0 μg L−1 of benzohydroxamic acid (BHA) as the complexing agent, after the GA process. Once optimized, analytical performance of the method was studied in terms of linearity (1.3–316 μg L−1, R2 = 0.999), accuracy (recovery = 90.1–92.3 %), and precision (relative standard deviation (RSD) <3.1). Finally, the method was successfully applied to speciate the iron species in the environmental and wastewater samples. © 2015, Springer International Publishing Switzerland. Source

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