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In this study, accurate and sensitive determination of ibuprofen in blood, urine, pharmaceutical tablet, syrup, and water samples was accomplished with the combination use of deep eutectic solvent-based ultrasound-assisted liquid–liquid microextraction (DES-UA-LLME) and high-performance liquid chromatography-ultraviolet visible detection system. The most important advantage of this method is that it can be used in the determination of ibuprofen without affecting the matrix environment of a wide range of samples. Ibuprofen in the sample phase was extracted to 500 µL of deep eutectic solvents phase (ChCl:Ph at 1:4 molar ratios) at pH 3.0. The influence of analytical parameters, such as pH of sample solution, the molar ratio of deep eutectic solvents components, tetrahydrofuran volume, and volume of DESs, were optimised in details. The preconcentration factor (PF), the detection limit (DL), intraday, and interday relative standard deviations (RSD, %) for the developed DES-UA-LLME/HPLC procedure were found as 30, 0.4 µg L−1, 1.74%, and 4.68%, respectively. The developed DES-UA-LLME was successfully used for the determination of ibuprofen in urine, blood, pharmaceutical tablet, syrup, and water samples. [ABSTRACT FROM AUTHOR]

Copyright of Nigde Omer Halisdemir University Journal of Engineering Sciences / Niğde Ömer Halisdemir Üniversitesi Mühendislik Bilimleri Dergisi is the property of Nigde Omer Halisdemir Universitesi (NOHU), Muhendislik Fakultesi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A micelle mediated separation and preconcentration method for flame atomic absorption spectrophotometric (FAAS) determination of Cu was developed. The method is based on complex formation between Cu and 1-(2-pyridylazo)-2-naphthol and cloud point extraction with Tergitol NP-7 surfactant prior to FAAS determination. The parameters affecting quantitative extraction of copper, including pH, surfactant and ligand concentrations, incubation time and temperature, were examined and optimized. Under optimum conditions, interference effects of other ions were studied, and tolerance ratios of interference ions were given. Under the optimal conditions, detection and quantitation limits were found as 3 and 8 [mu]g/L, respectively. Linear dynamic range for Cu.sup.2+ was determined to be 0.13-1.5 [mu]g/mL. Relative standard deviations were below 6% throughout the experiments. Enhancement factor was determined as 25. Applicability of the method was proved by analysis of standard reference materials. The developed method was applied to determine trace copper contents in different mushroom species., Author(s): Yeliz Camci [sup.1], Abdullah Taner Bisgin [sup.2], Yavuz Sürme [sup.1], Mustafa Uçan [sup.1], Ibrahim Narin [sup.3] Author Affiliations: (1) grid.412173.2, 0000 0001 0700 8038, Department of Chemistry, Faculty of [...]

Date-rape drugs given to victims through drinks without their knowledge in drug-facilitated sexual assaults and thefts (money, property and body organs), are important threats for the public. Detection in beverage residues gains importance, since some of them can be quickly eliminated from the body, till the victim understands what he/she has experienced, goes to the hospital and gives a urine sample for analysis. Here, date-rape drugs; ketamine, thiopental, phenobarbital, zolpidem, phenytoin and zopiclone were analyzed simultaneously in 1.00mL caffeine-based carbonated beverage residue, through direct injection, using a modified, economical emergency first-step screening method with high performance liquid chromatography-diode array detector (elution time: 11 minutes). Screening power of the method was qualitatively observed in sour cherry juice, sweet soda and beer with some additional experiments. Caffeine in caffeine-based carbonated beverage could also be detected simultaneously. LODs and LOQs were between 0.02-1.79 and 0.08-5.60µgmL-1. Repeatability and reproducibility values were <9.91%. HorRat values were between 0.184-0.500. As the first screening and quantitative study on the simultaneous analysis of these drugs in a beverage, it’s important for solving the crimes committed using drugs in caffeine-based carbonated beverage residues found at the crime scene, when the use of these drugs is suspected after anamnesis and inspection. [ABSTRACT FROM AUTHOR]

Amberlite XAD-7 and XAD-8 resins were used as adsorbents for preconcentration and determination of Allura Red ( AR) food dye in aqueous medium. The effects of pH, sample volume, sample and eluent flow rates on the extraction of AR were optimised. The determination of dye was performed at 506.0 nm using spectrophotometry. Interference effects of matrix ions and some dyes were also investigated under optimised conditions. The methods permitted low detection limits which were 1.2 and 0.6 μg L−1 for XAD-7 and XAD-8, respectively. Adsorption behaviours were investigated by adsorption isotherms and zero charge pH experiments. Validations of the method were performed by determination of AR contents in some foodstuffs. AR contents of liquid samples were found between 58 and 440 μg mL−1. AR concentrations of solid samples were between 416 and 432 μg g−1. The XAD-7 and XAD-8 resins presented a fast and reliable potential to determine AR dye in real samples. [ABSTRACT FROM AUTHOR]

This study deals with the preconcentration, determination, and removal of Lanaset Blue 2R textile dye from aqueous medium by two different methods. For this purpose, cloud point extraction (CPE) and solid phase extraction (SPE) methods were optimized. Amberlite XAD-1180 resin was used as adsorbent for SPE while Tergitol NP-7 non-ionic surfactant was used as surfactant rich phase for CPE. The common optimization steps were determined as initial solution pH, linear dynamic range, sample volume, equilibrium time and limits of detections were characterized for both SPE and CPE techniques while specific optimization steps such as temperature and surfactant concentration were also determined for CPE. The results showed that the CPE and SPE of dye were quantitative at pH 6. Detection limits were 21-μg L−1for CPE and 9-μg L−1for SPE. The enrichment factors were 40 and 10 for SPE and CPE, respectively. The real sample analysis was successfully performed with both techniques. The strengths and weaknesses of the methods were highlighted. [ABSTRACT FROM PUBLISHER]

The p K constants and relative abundances of unionized and ionized forms of Montelukast sodium {the sodium salt of 2-[1-[[(1 R)-1-[3-[2-(7-chloroquinolin-2-yl)ethenyl] phenyl]-3-[2-(2-hydroxypropan-2-yl)phenyl]propyl]sulfanylmethyl]cyclopropyl]acetic acid} and Levodropropizine {(2 S)-3-(4-phenylpiperazin-1-yl)propane-1,2-diol} were determined potentiometrically from measurements at various pHs. These determinations were in order to relate their p K values with their bioavailability and to provide chemical data to be used in their analysis. [ABSTRACT FROM AUTHOR]

The article focuses on a study which examined the synthesis and characteristics of water-soluble oligophenol derivative 4-(2-hydroxybenzylideneamino)benzenesulfanilic acid (OSAL-SA) and its metal complexes. Methanol was used to synthesize lead, copper and cobalt complexes of the polymer. Results of the study showed that the azomethine group in the complexes was involved in binding to the metal ions. It also found that one metal ion was coordinated to two OSAL-SA molecules for each complex.

A simple, fast, and sensitive column solid phase extraction study has been proposed for flame atomic absorption spectrometric determination of lead, cadmium, chromium, nickel, copper, and manganese ions on XAD-4 as 1-(2-pyridylazo)2-naphthol (PAN) complexes. The analytes were sorbed as PAN complexes on Amberlite XAD-4 column at the pH range of 8.5–10, and then eluted with 1 M HNO3 in acetone. The effect of pH, reagent amount, sample volume, and matrix of the sample on the sorption of metal ions has also been investigated. The concentration of analytes after separation and preconcentration was in agreement with the added amount of ions. The present method was found to be applicable to the preconcentration of analyte ions in river water from Yesilirmak, lake water from Lake Van, bottled mineral waters, tap water, stream sediment, mushroom, tobacco, and black tea samples with good results (recoveries greater than 95%, relative standard deviations lower than 10%). [ABSTRACT FROM AUTHOR]

1-(2-pyridylazo) 2-naphtol (PAN) impregnated Ambersorb 563 resin was used as solid phase extractor of copper, nickel, cadmium, lead, chromium and cobalt ions in aqueous solutions prior to their atomic absorption spectrometric determinations. The parameters including pH, sample volume, matrix effects were also investigated. The relative standard deviation (R.S.D.) of the combined method of sample treatment, preconcentration and determination with atomic absorption spectrometry is generally lower than 10%. The limit of detection was between 0.21 and 1.4 μg l−1. The results were used for preconcentration of analyte ions from natural water samples. The method was also applied to a stream sediment standard reference material (GBW7309) for the determination of Cu, Ni, Cd, Pb, Cr and Co. [Copyright &y& Elsevier]

A polystyrene divinylbenzene resin (Amberlite XAD-16) functionalized by 1-(2-pyridylazo) 2-naphtol has been synthesized and its sorption properties have been investigated for preconcentration of Ni(II), Cd(II), Co(II), Cu(II), Pb(II) and Cr(III) in natural water samples. The new resin (XAD-16-PAN) was characterized by thermogravimetric analysis and infrared spectrometry. The analytical parameters including pH, sample volume etc. for the quantitative recoveries of the analyte ions using XAD-16-PAN resin were investigated. The effects of alkaline, earth alkaline ions and some anions on the sorption of analyte ions were also examined. The recovery values were greater than 95% and the preconcentration factor was 200 for all analyte ions. The relative standard deviations of the determinations by flame atomic absorption spectrometry were less than 8%. The detection limits of the analyte ions (k=3, N=21) were varying from 0.056 μg/L for Cd to 0.268 μg/L for Cr. [ABSTRACT FROM AUTHOR]

A simple method has been established for speciation of chromium(III) and chromium(VI) in natural water samples. The method is based on the solid phase extraction of the Cr(VI)-APDC chelate on the Ambersorb 563 carbonaceous resin filled mini-column. After oxidation of Cr(III) to Cr(VI) by using H[sub 2]O[sub 2], the method was applied to the determination of the total chromium. The level of Cr(III) is calculated by difference of total chromium and Cr(VI) concentrations. The influences of the various analytical parameters including pH, amounts of reagents, sample volume on the quantitative speciation values of chromium were investigated. Recoveries of more than 95% were found. No interferences due to major components of the natural water samples and some metal ions were observed. The detection limit based on the 3σ criterion was 2.70 µg/L for Cr(VI). The presented method was applied for the speciation of the chromium in the tannery wastewater samples from Bor Organized Industrial Region-Nigde (Turkey) with satisfactory results (recoveries >95%, RSD's < 9%). [ABSTRACT FROM AUTHOR]

A separation/enrichment procedure has been established for atomic absorption spectrometric determination of some trace metal ions by using a column filled Amberlite XAD-2000 resin. It is based on the sorption of metal ions on XAD2000 as 1-(2-pyridylazo) 2-naphtol (PAN) chelates. Following washing of the XAD-2000 column with blank solution, metal-chelates were eluted by 1 M nitric acid in acetone and determined by flame atomic absorption spectrometry (FAAS). The influences of some analytical parameters including pH, amounts of PAN, sample volume, also effects of concomitant ions were investigated. The procedure was applied to sea water samples collected from Mersin BayMediterranean Sea with satisfactory results (recoveries > 95%, relative standard deviations < 9%). [ABSTRACT FROM AUTHOR]

• A green hydrothermal production method was used for magnetic carbon nanodot/graphene oxide (Fe3O4@C-nanodot@GO). • Magnetic solid phase extraction (MSPE) method was developed for ibuprofen in human plasma prior to HPLC-DAD determination. • C-nanodots were produced from pasteurized cow milk. • Concentration changes of ibuprofen in human blood against time was successfully monitored. In this study, a green production method was used to obtain magnetic carbon nanodot/graphene oxide hybrid material (Fe 3 O 4 @C-nanodot@GO) for the magnetic solid phase extraction (MSPE) of ibuprofen (IBU) in human plasma prior to HPLC-DAD determination. For the first time in the literature, Fe 3 O 4 @C-nanodot@GO hybrid material was synthesized and used as an adsorbent. C-nanodots were produced from pasteurized cow milk by using a simple and cheap hydrothermal method. After production of the C-nanodots and GO, Fe 3 O 4 @C-nanodot@GO hybrid material was fabricated in green solvent medium by using an one-step hydrothermal method. The method was based on the simple separation, preconcentration and analysis of ibuprofen by using MSPE-HPLC-DAD combination. The concentration changes of ibuprofen in human bloods against time were successfully monitored by using this combined method. For this purpose, blood samples were taken from volunteers at certain intervals after the administration of a certain dose of ibuprofen, and the MSPE method was used to monitor the concentration changes of ibuprofen in the blood samples. Experimental variables affecting the extraction efficiency of IBU such as sample solution pH, amount of adsorbent, extraction time, eluent type and volume were studied and optimized in the details. The characterization studies for the Fe 3 O 4 @C-nanodot@GO were carried out by X-ray diffraction spectrometry (XRD), Fourier transform infrared spectrometry (FT-IR), Raman spectrometry (Raman), energy dispersive x-ray (EDX), vibrating sample magnetometry (VSM) and scanning electron microscopy (SEM) techniques. Under the optimum experimental conditions, the limit of detection (LOD) was 8.0 ng mL−1 and the recoveries at three spiked levels in human plasma were ranged from 91.0% to 95.0% with the relative standard deviation (RSD %) less than 4.0 % (n = 6). The results show that together use of MSPE with HPLC-DAD provides a simple and rapid analysis of ibuprofen in human plasma samples. [ABSTRACT FROM AUTHOR]

Two novel spectrophotometric determination procedures based on retention of Allura Red onto Amberlite XAD-1180 and XAD-16 resins for its preconcentration, purification, and separation were developed. Analytical parameters of the methods including pH, eluent type, sample volume, and sample and eluent flow rates, were investigated and optimized. Interference effects of some cations, anions, and widely used food dyes were also investigated. Detection limits of the two methods were found to be 1.2 and 1.5 μg/L for XAD-1180 and XAD-16 columns, respectively, under optimum conditions. Linear calibration curve ranges of the methods were 0.4-8.0 and 0.5-6.0 μg/mL of Allura Red for XAD-1180 and XAD-16 resins, respectively. Preconcentration factors were found as 80 for both the XAD-1180 and XAD-16 columns using maximum sample volume and minimum eluent volume. RSDs of the methods were below 6% throughout all experiments. All absorbance measurements were performed at 506 nm. Validations of the methods were performed comparatively with determination of the Allura Red contents of some foodstuff, pharmaceutical, and energy drink samples. Allura Red concentrations in investigated solid and liquid samples ranged from 298 to 501 μg/g and 53.8 to 508 μg/mL, respectively. Satisfactory results were obtained from the real samples analysis. Allura Red contents of samples were determined to be highly similar using the two extraction methods. Comparisons of the methods were performed by analysis of Allura Red contents of the real samples. In addition to analytical parameters, adsorption isotherm studies were performed for the two kinds of Amberlite resins. It was observed that developed methods fit the linear form of the Freundlich adsorption isotherm model. All of the experimental results suggested that the developed SPE procedures are suitable for separation, preconcentration, and determination of Allura Red in solid and liquid matrixes. [ABSTRACT FROM AUTHOR]

Abstract: A coprecipitation procedure has been presented prior to flame atomic absorption spectrometric determination of nickel, cadmium and lead ions in environmental samples. Analyte ions were coprecipitated by using copper hydroxide precipitate. The influences of some analytical parameters like amounts of copper, sample volume, etc., on the recoveries of the analytes were investigated. The interference of other ions was negligible. Under the optimized conditions, the detection limits (3 sigma, n =15) of lead(II), nickel(II) and cadmium(II) were 7.0, 3.0 and 2.0μg/L, respectively. The proposed method has been successfully applied for the determination of traces of Ni, Cd and Pb in environmental samples like tap water. [Copyright &y& Elsevier]

Aclidinium bromide (ACL) is a long-acting muscarinic receptor antagonist used for the long-term treatment of chronic obstructive pulmonary disease (COPD). The aim of this study was to investigate the degradation of aclidinium bromide under stress and stability testing conditions, for which we developed and validated the first stability-indicating, specific, precise, accurate, and robust assay and related substances HPLC methods. Nine of the compounds used as reference standards were synthesized and fully characterized by 1H and 13C NMR, MS, and FTIR techniques. Two of these molecules, namely ACL-dimer and ACL-desphenyl, are novel compounds and reported herein for the first time. Hydrolysis of aclidinium resulted in major degradation via the formation of ACL-desDTG and DTGA metabolites. ACL-desphenyl and phenol were observed only under oxidative conditions at very low levels (< 0.10%), while ACL-hydroxy, known as a metabolite of aclidinium and confirmed by LC/QDa and LC/Q-TOF m/z data, formed under oxidative stress-testing conditions, UV light, and daylight. The identification of two impurities formed only when aclidinium bromide was treated with hydrogen peroxide was done by LC/QDa and LC/Q-TOF studies and the novel structures were proposed as ACL-bromophenoxy and ACL-bromothiophenyl formed via bromination of the phenyl and thiophene ring on the aclidinium, respectively. The stress and photostability testing studies showed that the aclidinium bromide drug substance is not sensitive to elevated temperature (105 °C, 10 days), slightly sensitive to daylight and UV-radiation, and it showed significant degradation under all hydrolysis and oxidizing conditions. The related substances HPLC method reported herein is also capable to monitor the potential genotoxic impurity 3-bromopropoxybenzene (3-BPB), a class 2 impurity according to ICH M7, and ensures that the impurity remains below the threshold of toxicological concern (TTC) limit, making it safe for patients. [Display omitted] • Stability-indicating related substances & assay HPLC methods for aclidinium bromide. • Evaluation, synthesis, and characterization of nine compounds by NMR, MS, and FTIR. • Degradation of aclidinium bromide studied under stress test conditions. • Identification of degradation impurities by LC-MS & discussion of formation pathways. • Four new compounds described for the first time in the literature. [ABSTRACT FROM AUTHOR]