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Combination treatment enhances efficacy, minimizes side effects, and improves convenience for patients with diverse treatment schedules. This compilation focuses on the simultaneous estimation of Miconazole nitrate (MNE), Mupirocin (MRN), and Mometasone furoate (MMT) using HPLC and HPTLC in an ointment which is wisely used combination for treatment of skin disorders. The optimized isocratic HPLC method consists of a C18 column, 0.02% triethylamine: methanol (15:85; % v/v), at a flow rate of 0.9 mL/min. The retention times were found to be 4.716 ± 0.082 min for MNE, 13.716 ± 0.188 min for MRN, and 2.241 ± 0.034 min for MMT using the developed method. The method was validated indetail and the quantification range found 20–180 µg/mL for both MNE and MRN and 1–9 µg/mL for MMT. In an alternative HPTLC method, toluene, ethyl acetate, and ethanol (10:3:2; v/v/v) were used as mobile phase on silica gel 60F254-coated aluminum sheets, with scanning at 240 nm. The MNE, MRN and MMT drugs spot eluted at Rf values of 0.65, 0.36, and 0.80, respectively. In-depth validation was performed and assessed statistically, including, specificity, precision, accuracy, reproducibility, and accuracy. The HPTLC method found linear in ranges of 1200–5200 ng/band for MNE and MRN, and 60–260 ng/band for MMT. Consequently, these developed chromatographic methods assessed according to green analytical principle and found sustainable. The developed methods can be effectively applied for the quantitative analysis of commercially available dosage forms. [ABSTRACT FROM AUTHOR]

Interest in measuring major and trace elements in plants has increased in recent years because of growing concerns about the elements’ contribution to daily intakes or the health risks posed by ingesting vegetables contaminated by potentially toxic elements. The recent advances in using inductively coupled plasma atomic emission spectrometry (ICP-OES) to measure major and trace elements in plant samples are reviewed in the present work. The sample preparation before instrumental determination and the main advantages and limitations of ICP-OES are described. New trends in element extraction in liquid solutions using fewer toxic solvents and microextractions are observed in recently published literature. Even though ICP-OES is a well-established and routine technique, recent innovations to increase its performance have been found. Validated methods are needed to ensure the obtaining of reliable results. Much research has focused on assessing principal figures of merit, such as limits of detection, quantification, selectivity, working ranges, precision in terms of repeatability and reproducibility, and accuracy through spiked samples or certified reference materials analysis. According to the published literature, the ICP-OES technique, 50 years after the release of the first commercially available equipment, remains a powerful and highly recommended tool for element determination on a wide range of concentrations. [ABSTRACT FROM AUTHOR]

A novel green microextraction supramolecular (SUPRA)-based method for simultaneous preconcentration of seven pesticides, acetamiprid, azoxystrobin, bifenthrin, carbendazim, chlorpyrifos, imidacloprid, and tebuconazole, in water samples and cereal flours with further determination by HPLC-DAD was developed. The method uses 113 µL of 1-decanol as amphiphilic extractor and 500 µL of tetrahydrofuran as disperser solvent. To perform the method optimization, a 25 factorial design and Doehlert design combined with Derringer–Suich desirability function and response surface methodology were used. The microextraction of the pesticides was carried out at pH 6.3 in the presence of 5% NaCl (w/v), low vortex-assisted extraction time (30 s) and it was provided high preconcentration factors (3.6–266.1), and low LOQs (8.98–29.92 µg L−1). The intra-day (n = 10) and inter-day (n = 10) precision assessed as the percentage of relative standard deviation (%RSD) for concentrations of 50.0 and 200.0 µg L−1 varied from 1.7 to 4.1%. The method was successfully applied to determine pesticides in river and lake water samples using external calibration curves. Considering the property of restricted access materials of SUPRAs, the microextraction method was also applied to the direct treatment of solid samples of wheat, oat, and rice flours. High recovery values in the range of 80–112% were obtained, thereby proving the absence of possible interference from matrix components. [ABSTRACT FROM AUTHOR]

Irritable bowel syndrome (IBS) is a world‐wide disease prevalently in Western nations. It influences about 15% of the western populace, with a negative effect on the quality of life and furthermore on medical services costs. Anticholinergic antispasmodics are first line of treatment for discomfort or abdominal pain, particularly if unrelieved after alleviation of stoppage or antidiarrheal treatment. Otilonium bromide (OTB) is quaternary ammonium compound with action on distal GI tract as antispasmodic. It is utilized in the treatment of patients influenced by Irritable inside disorder (IBS) because of its particular pharmacokinetic and pharmacodynamic properties. OTB is poorly absorbed systematically was viable in contrast with different medications used for same purpose, for example, pinaverium bromide and mebeverine, with a good tolerability profile. The effects are long lasting, even after stopping the dosage regime for reduction of abdominal pain. In this review, an overview of mechanism of action, pharmacologic action, synthesis and particularly various analytical and bioanalytical methods are discussed. The analytical methods discussed are spectrophotometry including Near Infrared Spectroscopy (NIRS), chromatography and capillary electrophoresis methods are described with the range, limit of detection and quantification. The paper also provides details of scope of further extension of analytical methods. It was found that most of the analytical methods involves usage of toxic solvents e.g., methanol, acetonitrile, chloroform etc. posing risk to the analyst as well as environment. [ABSTRACT FROM AUTHOR]

A fast and green ultra‐high‐performance liquid chromatographic method was developed for the determination of ibuprofen in milk‐containing simulated gastrointestinal media to monitor the dissolution of three‐dimensional printed formulations. To remove interfering compounds, protein precipitation using methanol as a precipitation reagent was performed. The separation of the target analyte was performed on a C18 column using a mobile phase consisting of 0.05% v/v aqueous phosphoric acid solution: methanol, 25:75% v/v. Method validation was conducted using the total error concept. The β‐expectation tolerance intervals did not exceed the acceptance criteria of ±15%, meaning that 95% of future results will be included in the defined bias limits. The relative bias ranged between ─1.1 and +3.2% for all analytes, while the relative standard deviation values for repeatability and intermediate precision were less than 2.8% and 3.9%, respectively. The achieved limit of detection was 0.01 μg/ml and the lower limit of quantitation was established as 2 μg/ml. The proposed method was simple, and it required reduced organic solvent consumption following the requirements of Green Analytical Chemistry. The method was successfully employed for the determination of ibuprofen in real biorelevant media obtained from dissolution studies. [ABSTRACT FROM AUTHOR]

A green flow injection spectrophotometric technique for the determination of ascorbic acid was described based on the redox and complexation reactions. Iron(III) was reduced to iron(II) by ascorbic acid with subsequent complexation reaction of remaining iron(III) with a natural reagent extracted from Areca catechu L. at pH 5.0 yielding a dark-blue color. Absorbance decreased with increasing ascorbic acid concentration. A linear range of 1–10 mg/L for ascorbic acid was obtained with r2 of 0.9986. Limit of detection and limit of quantification were 0.3 and 0.9 mg/L, respectively. Relative standard deviation was less than 5.0%. This method was utilized to quantify ascorbic acid in pharmaceuticals and soft drinks with a sampling rate of 40 h−1. Ascorbic acid contents of 96–100% in pharmaceutical samples were obtained, while recoveries for spiked ascorbic acid standard at 3 mg/L in soft drinks were 92–113%. [ABSTRACT FROM AUTHOR]

This work emphasizes the utilization of biochar, a renewable material, as an interesting platform for anchoring redox mediators and bioreceptors in the development of economic, environmentally friendly biosensors. In this context, Fe(III) ions were preconcentrated on highly functionalized activated biochar, allowing the stable synthesis of Prussian blue nanostructures with an average size of 58.3 nm. The determination of glucose was carried out by indirectly monitoring the hydrogen peroxide generated through the enzymatic reaction, followed by its subsequent redox reaction with reduced Prussian blue (also known as Prussian white) in a typical electrochemical-chemical mechanism. The EDC/NHS (1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride and N-Hydroxysuccinimide) pair was employed for the stable covalent immobilization of the enzyme on biochar. The biosensor demonstrated good enzyme-substrate affinity, as evidenced by the Michaelis-Menten apparent kinetic constant (4.16 mmol L−1), and analytical performance with a wide linear dynamic response range (0.05–5.0 mmol L−1), low limits of detection (0.94 μmol L−1) and quantification (3.13 μmol L−1). Additionally, reliable repeatability, reproducibility, stability, and selectivity were obtained for the detection of glucose in both real and spiked human saliva and blood serum samples. [Display omitted] • A simple, sustainable electrochemical biosensor has been developed. • Activated biochar was responsible for the anchoring of nanostructures and enzymes. • Prussian blue nanostrucutres were electrochemically synthesized on biochar. • The biosensor showed good enzyme-substrate affinity and analytical performance. • The enzymatic detection of glucose was performed in human biological samples. [ABSTRACT FROM AUTHOR]

An ultrasound-assisted, one-pot cloud point extraction was developed for the determination of iron in vegetable samples by UV-Visible spectrophotometry. This method was based on the complexation of iron with an environmentally-friendly natural chelating agent extracted from Dipterocarpus intricatus Dyer fruit at pH 5.5 in the presence of Triton X-114. Reagent extraction, complexation, and preconcentration were performed simultaneously using ultrasound-assisted extraction at 45 °C. The surfactant-rich phase was diluted with ethanol and loaded through a syringe barrel packed with cotton that acted as a filter to trap the reagent powder. Analyte-entrapped on cotton was eluted using 0.1 mol·L−1 nitric acid solution. Filtrate and eluate solutions were measured absorbance of the dark-blue product at 575 nm. Influential parameters for the procedure were investigated. Under the optimum experimental conditions, the calibration curve was linear, ranging from 0.1 to 1.0 mg·L−1 with r2 = 0.997. Limits of detection and quantification were 0.03 and 0.09 mg·L−1, respectively while precision values of intra-day and inter-day were less than 5%. Recovery at 0.5 mg·L−1 ranged from 89.0 to 99.8%, while iron content in vegetable samples ranged from 2.45 to 13.36 mg/100 g. This method was cost-effective, reliable, eco-friendly, and convenient as a green analytical approach to determining iron content. [ABSTRACT FROM AUTHOR]

This study used a green validated method to evaluate the risk of exposure of individuals of different ages to acrylamide (AA) and 5-hydroxymethylfurfural (5-HMF) by consuming white and wholewheat bread. Recoveries of AA and 5-HMF were 100.7% and 100.1%, respectively, while uncertainty was 2.3% and 6.2%. Levels of AA ranged from 617.22 to 3151.8 μg/kg while levels of 5-HMF ranged from 180.5 to 648.2 μg/kg. Female adolescents were almost 2-fold exposed to AA when they consumed 100% wholewheat bread (2.93 μg/kg bw/day) by comparison with white bread (1.72 μg/kg bw/day). Estimated daily exposure to AA was 1.5-fold higher than international recommendations. These findings raise concern for health risks associated with exposure to processing contaminant as the result of bread consumption, especially made from whole grains. Since development of those compounds is inevitable during breadmaking, it is crucial to standardize processing conditions and recipes to mitigate it. [Display omitted] • A method of extraction of acrylamide and 5-HMF with methanol was adapted. • The risk estimation of acrylamide and 5-HMF presences during breadmaking. • Wholewheat bread was the most contaminated one by acrylamide and 5-HMF. • Acrylamide levels were almost 5-fold higher than those of 5-HMF. • Risk of exposure to processing contaminants in bread is worrisome. [ABSTRACT FROM AUTHOR]

A new and revolutionary material, called, Solid Eutectic Systems (SES) based on natural compounds are presented, prepared, and characterized for the first time. Matrix Solid-Phase Dispersion (MSPD) was used to extract and preconcentrate five important phenolic compounds from Lactuca sativa. SES based on thymol and citric acid (TC 1:1) and a Natural Deep Eutectic Solvent (NADES) based on lactic acid, glucose, and water (LGH 5:1:8) were selected as the most effective sorbent and eluent, respectively. The variables that influence the MSPD parameters were optimized: 100 mg of dried lettuce, 400 mg of TC 1:1 sorbent, 30 s of grinding time, and 1430 μL of LGH 5:1:8, obtaining AGREE and AGREEprep scores of 0.90 and 0.72. Recoveries (%) of the phenolic compounds were 70 to 115 %, with a relative standard deviations lower than 12 %. Finally, the limits of detection and quantification were 1.7–2.2 µg g−1 and 5.1–6.7 µg g−1, respectively. SES marks a transformative milestone, providing eco-friendly solutions with a streamlined preparation process. The versatile sample preparation ensures efficient cleanup across various matrices. Enhanced simplicity and adaptability can result from intelligent sorbent development for improved selectivity and sensitivity. In this study, SES was introduced as a novel green sorbent for MSPD, efficiently extracting phenolic compounds from lettuces. [Display omitted] • Solid Eutectic Systems are prepared and characterized for the first time. • Eutectic systems were applied as sorbent and eluent in matrix-solid phase dispersion. • Important phenolic compounds were successfully extracted from lettuce samples. • AGREE® and AGREEprep® showed scores of 0.91 and 0.72, respectively. • ChlorTox demonstrated that the methodology presented low chemical risk. [ABSTRACT FROM AUTHOR]

The ability of nuclear magnetic resonance spectroscopy (NMR) to extract chemical information from a complex mixture is invaluable and widely described in literature. Many applications of this technique in the foodomics field have highlighted how NMR could characterize food matrices, and it can be used all along its “life chain”: from farm to fork and from fork to the digestion process. The aim of this review is an attempt to show, firstly, the potential of NMR as a method based on green chemistry in sample preparation, and then in characterizing the nutritional qualities of agri-food products (with particular attention to their by-products) from a sustainable point of view. For instance, the NMR-based metabolomics approach has been used to enhance the nutritional properties of bio-products waste naturally rich in antioxidants and prebiotics. The reintroduction of these products in the food supply chain as functional foods or ingredients answers and satisfies the consumer demand for more food with high nutritional quality and more respect for the environment.

An ultrasound-assisted, one-pot cloud point extraction was developed for the determination of iron in vegetable samples by UV-Visible spectrophotometry. This method was based on the complexation of iron with an environmentally-friendly natural chelating agent extracted from Dipterocarpus intricatus Dyer fruit at pH 5.5 in the presence of Triton X-114. Reagent extraction, complexation, and preconcentration were performed simultaneously using ultrasound-assisted extraction at 45 °C. The surfactant-rich phase was diluted with ethanol and loaded through a syringe barrel packed with cotton that acted as a filter to trap the reagent powder. Analyte-entrapped on cotton was eluted using 0.1 mol·L−1 nitric acid solution. Filtrate and eluate solutions were measured absorbance of the dark-blue product at 575 nm. Influential parameters for the procedure were investigated. Under the optimum experimental conditions, the calibration curve was linear, ranging from 0.1 to 1.0 mg·L−1 with r2 = 0.997. Limits of detection and quantification were 0.03 and 0.09 mg·L−1, respectively while precision values of intra-day and inter-day were less than 5%. Recovery at 0.5 mg·L−1 ranged from 89.0 to 99.8%, while iron content in vegetable samples ranged from 2.45 to 13.36 mg/100 g. This method was cost-effective, reliable, eco-friendly, and convenient as a green analytical approach to determining iron content.

Carbendazim is a fungicide used for pest control in fruit crops. However, carbendazim is dangerous to human health and the environment, requiring monitoring by appropriate analytical methods. For this, a square-wave anodic stripping voltammetric method was developed for the first time for determining carbendazim in orange and pineapple juices. As a sensor, the proposed method uses a carbon paste electrode modified with cobalt phthalocyanine. The optimized voltammetric parameters were: rest time = 5 s, pulse amplitude = 30 mV, potential increment = 1.0 mV, frequency = 20 s−1, potential window ranging from + 0.6 to + 1.1 V, peak potential (+0.90 V) and deposition time = 45 s. The method presented a linear response (r2 = 0.994, n = 8, limits of detection = 0.57 nmol L−1) from 49.7 to 384.6 nmol L−1 carbendazim, good reproducibility (relative standard deviation = 2.4 %) and accuracy (recovery rates = 93.3–107.9 %). The proposed method is superior to other methods reported in the literature because the preparation of the sensor is faster, as well as being simple, sensitive, selective, low-cost, high-frequency analysis, and eco-friendly as it does not use any sample pre-treatment (sonication, centrifugation, filtration, pre-concentration, dilution and/or extraction with organic solvents). • First carbendazim study on carbon paste electrode modified with cobalt phthalocyanine; • Presentation of a new voltammetric method for determining carbendazim in fruit juice; • Effective combination of square wave voltammetric and standard addition procedures; • Good reproducibility (RSD = 2.4 %) and accuracy (recovery rates = 93.3–107.9 %); • Useful alternative for routine analyses of foods without sample pretreatment. [ABSTRACT FROM AUTHOR]

Donepezil hydrochloride is one of the most prescribed anti-Alzheimer's drugs, despite being available for more than two decades, chromatographic methods for the quantification of the drug in biorelevant media that mimics pH physiological conditions in vivo (pH 1.2, 4.5, and 6.8) are not available in the literature. These media are used in the dissolution test, an important tool, for registration and quality control of medicines. Considering the need for methods with this purpose, this work aimed to develop and validate a sustainable UPLC-UV method for quantification of donepezil hydrochloride in tablets, specifically on assay and dissolution profile, with reduced environmental impacts. The proposed method has a run time of 2 min and requires for each run, only 0.8 mL of solvents, providing excellent green analysis. The method proved to be selective, linear, precise, accurate, robust in the range of 2–14 µg/mL. Three products (reference, similar, and generic) were analyzed and showed very rapid dissolution. The average content varied from 100.2 ± 0.6% to 109.5 ± 2.1%. Using dissolution efficiency (DE), the drug release profiles were compared in different biorelevant media. [ABSTRACT FROM AUTHOR]

The potential of a low-cost (∼US$ 1000) portable near-infrared (NIR) spectrophotometer for in situ characterization of seized cocaine samples was evaluated. A set of 240 samples of cocaine seized in several regions and cities across Brazil by its federal police was employed in this study. These samples were previously analyzed by chromatography at the Forensic Chemistry Laboratory of the National Institute of Criminalistics in Brasília-DF for the contents of several constituents to chemically characterize the samples. A low-cost NanoNIR spectrophotometer (Texas instruments) was used to acquire the NIR spectra of the samples in the range 900–1700 nm. The spectra set was treated by the second derivative to construct and validate multivariate regression (Partial Least Square – PLS) and classification (software independent modeling of class analogy – SIMCA) models aiming to characterize the samples. Consequently, an informative toll for objective decision making could be used by the police agents to produce immediate answers to forensic questions raised at the point of seizing. Among those questions the most relevant are: does the seized sample contain cocaine? what is the cocaine form? what is its content? is the sample adulterated and/or diluted? what is the content of adulterant? is the sample significantly adulterated and/or diluted? what is the degree of oxidation of the cocaine? The results of this work allow to propose a NIR/chemometrics based analytical protocol providing fast answers to these questions with satisfactory confidence level for the purpose of reliably screen the seized samples. Image 1 • Portable and low-cost near-infrared for in situ profiling of seized cocaine. • Cocaine forms are positively identified and quantified in seized samples. • Adulterants and purity of seized cocaine are identified and quantified. • Near-infrared equipment costing less than US$ 1000 allows cocaine profiling. [ABSTRACT FROM AUTHOR]

Crude aqueous extract from the orchid ‘Dendrobium Sonia earsakul’ was utilised as a natural product reagent in flow injection analysis (FIA) incorporating a gas diffusion unit (GD) for the determination of ammonia nitrogen. Sample solution was injected into a NaOH donor stream to generate ammonia gas (NH3). In the GD unit, NH3 diffused across a PTFE gas-permeable membrane into the acceptor stream of the orchid extract. As the result, the aqueous orchid reagent became more alkaline and its colour changed from purple to green. The change in the colour of orchid acceptor correlated with the concentration of ammonia nitrogen in the sample and its absorbance monitored by a spectrophotometer at 600 nm. Ammonia nitrogen in chemical fertiliser samples and wastewater samples from agricultural fields were determined and reported as %N (w/w) and mg N L−1, respectively. For chemical fertilisers which contained high content of ammonia nitrogen, a flow rate of 1.0 mL min−1 and injection volume of 100 µL were used with a linear range of 5-40 mmol L−1 and detection limit of 2.12 mmol L−1. However, a higher sensitivity was required for wastewater samples having low ammonia nitrogen content. The flow rate was reduced to 0.3 mL min−1 and the injection volume increased to 1000 µL. As a result, detection limit of 0.76 mmol L−1 was achieved with linear range of 1-5 mmol L−1. The results of our method agreed well with that using the OPA method employing fluorescence detection. [ABSTRACT FROM AUTHOR]

This study aimed to develop and optimize a β-cyclodextrin (β-CD)-based technique for extracting anthocyanins from Lycium ruthenicum Murr. and to establish a ultra-high-performance liquid chromatography-diode array detector (UPLC-DAD) method for their analysis. β-CD solutions produced higher extraction yields of petunidin-3-O-(trans-p-coumaroyl)-rutinoside-5-O-glucoside and total anthocyanins from L. ruthenicum fruit than did pure water and aqueous hydroxypropyl-β-cyclodextrin (HPβ-CD) and ethanol and methanol solutions. Extraction at 50 °C for 30 min using 1.65% β-CD solution and a liquid/solid ratio of 15:1 produced the optimal extraction yield of L. ruthenicum anthocyanins. A UPLC-DAD method was developed for the determination of L. ruthenicum anthocyanins using an ethanol-based mobile phase, and the primary anthocyanins were identified using two-dimensional LC-MS/MS. Method validation showed that the developed method was accurate, stable, and reliable for the analysis of petunidin-3-O-(trans-p-coumaroyl)-rutinoside-5-O-glucoside and total anthocyanins from L. ruthenicum fruit. The present study showed that β-CD-based extraction coupled with UPLC-DAD analysis is an efficient and green method for the extraction and analysis of anthocyanins from L. ruthenicum fruit. [ABSTRACT FROM AUTHOR]

In this work, we developed and optimized a method for the analysis of PAHs and nitro-PAHs in atmospheric particulate matter (PM) samples by using thermal desorption gas chromatography coupled with electron ionization single quadrupole mass spectrometry (TD-GC-(EI)-MS). The method uses thermal desorption from a PM on a filter sample as means of sample introduction to a column and obviates the need for complex extraction procedures, which are time-consuming and require environmentally unfriendly solvents. Moreover, the possibility of systematic errors is minimized and a significantly smaller amount of sample is required compared to traditional techniques requiring a pre-extraction step (approx. 10-times). Thirteen PAHs and three nitro-PAHs were used during method development. Although Tenax cartridges are typically used to capture volatile pollutants from the air, we found that glass-wool liner is the most suitable trap for the examined analytes after desorption from a quartz filter. Among the various instrument parameters which were tested and optimized, TD desorption flow and hold time, and temperature of the cooled injection system (CIS) proved to be most critical. We also found out that the matrix effect is especially pronounced in the case of high PM loadings, which should be kept in mind when planning the analysis. After the optimization, standard reference materials (ERM-CZ100 and NIST 1648a) were used for partial method validation and finally, real PM 10 and PM 2.5 samples from two Slovenian cities were successfully analyzed. [Display omitted] • Simultaneous PAH and nitro-PAH determination in ambient PM without extraction. • Thermal desorption gas chromatography with electron ionization mass spectrometry. • Nitro-PAHs are successfully analyzed with TD-GC-(EI)-MS for the first time. • Much smaller amount of sample is needed compared to traditional methods. • Green method is suited for a better time resolution and SOA formation studies. [ABSTRACT FROM AUTHOR]

A novel method for automated determination pectin degree of esterification (DE) using micro sequential injection lab-on-valve (μSI-LOV) system is developed. A face-centered central composite response surface methodology (RSM) was used to optimise system parameters. A calibration graph for determination of non-esterified galacturonic acid (GalA) content in pectin solutions with linear range of 0.08–0.34% ( w / v ) and the limit of detection (LOD) of 0.057% ( w / v ) under optimal condition was achieved. The difference between concentrations ( w / v , %) of total GalA and non-esterified GalA was applied to estimate DE (%) of pectin samples. Results indicated a good agreement ( t stat < t crit ) and correlation ( R 2 = 0.998) between proposed automated method and the manual reference method. The current method provided precision of less than 6% RSD, ( n = 10) with sample throughput of 15 samples h −1 . The presented method requires remarkably low consumption of sample and reagents and is thereby environmental friendly. [ABSTRACT FROM AUTHOR]

[Display omitted] • Novel RID-HPLC method development for NAR quantification without derivatization. • Forced degradation was performed to detect degradation peaks and stability of NAR. • The developed method was validated as per FDA guidelines and applied to feed premix. • Greenness profile of the developed method was evaluated using GAPI and AGREE tools. Narasin (NAR) is a commonly used ionophoric antibiotic used in the poultry industry, cattle and pig production both for treating coccidiosis and increasing feed conversion efficiency. To ensure safe administration of NAR into the feed is important to avoid toxicity to farm animals caused by incorporation of large doses or non-homogenous mixing, which requires a simple and sensitive chromatographic method to quantify NAR. However, NAR detection by HPLC is challenging as it lacks a chromophore making it less susceptible to UV and fluorescence detection, and the published analytical methods suffer from disadvantages such as the need for complex derivatization or the use of high volumes of hazardous organic solvents. Herein, a novel, simple, rapid, and cost-effective HPLC method is reported to quantify NAR and a study of forced degradation under acidic, basic, temperature, and oxidative conditions are proposed. The separation was performed using a Phenomenex C18 analytical column (4.6 × 150 mm, 5 μm) and the mobile phase composed of 920 mL methanol, 80 mL water and 10 mL glacial acetic acid. A flow rate of 1 mL/min, and sample injection volume of 50 μL was used to detect NAR using the refractive index detector. The HPLC method was validated according to FDA guidelines and was found to be accurate, precise, sensitive and robust. It was shown to be linear at ranges of 200 to 900 µg/mL with a limit of detection (LOD) and limit of quantitation (LOQ) of 7.1 µg/mL and 21.5 µg/mL respectively. The method was successfully used to quantify the drug in its commercial formulation and a forced degradation study was performed under acidic, basic, temperature, and oxidative conditions. The greenness profile of the method was also investigated and compared to reported methods using the green analytical procedure Index (GAPI), and Analytical GREEnness Metric Approach and Software (AGREE) tools. The results indicated the greenness of the developed method. [ABSTRACT FROM AUTHOR]

Direct determination of cocaine in untreated seized samples has beenmade based on diffuse reflectance measurements of the near infrared (NIR) radiation through samples contained inside standard glass vials. The method used a series of previously analyzed samples, by the reference gas chromatography method, to build a partial least squares calibration model which was validated using an independent set of samples. The use of a generalmodel for samples containing from 11.38% till 86.44% (w/w) cocaine was based on the use of spectral ranges from 12500.7 to 10128.6, 9339.8 to 6967.7 and 5388.3 to 4597.6 cm-1 with previous first derivative and vector normalization data pre-processing and provided a root mean square error of prediction (RMSEP) of 4.0% (w/w) with a residual prediction deviation (RPD) of 3.9% (w/ w), based on the use of 8 latent variables, 34 samples for calibration and an independent set of 44 samples for validation. The aforementioned results could be improved on considering two separate models, one for high concentrated bulk samples and another for samples diluted with cutting agents. Additionally a new set of batch samples with cocaine concentrations from 60% till 84% was evaluated by using the developed method. [ABSTRACT FROM AUTHOR]

Highlights: [•] A simple and fast method for Na and K ultrasound extraction in swine feed has been developed. [•] Requires only minutes to accomplish. [•] Excellent results have been achieved with ultrasound-assisted extraction. [•] Green chemistry-type procedure. [•] The proposed method has the advantage of does not generating toxic residues. [Copyright &y& Elsevier]

Abstract: In this work, a new method based on the combination of dispersive liquid–liquid microextraction (DLLME) with microvolume spectrophotometry has been developed as a greener and miniaturized alternative to the 5530 APHA standard method for determining phenols in water and wastewater. The method relies on the oxidative coupling of phenols with 4-aminoantipyrine (4-AAP). In order to preconcentrate the dye formed, the classical liquid–liquid extraction used in the 5530 APHA method (involving 500mL of sample and 50mL of trichloromethane) has been replaced by DLLME (with 5mL of sample, 50μL of trichloromethane and 200μL of acetonitrile). After optimization, the method yielded limits of detection and quantification (0.8 and 2.5μgL−1, respectively) that were comparable with those obtained by the 5530 APHA standard method. Repeatability, expressed as relative standard deviation, was 5.2% (N=6), and the enrichment factor (EF) was 700. The proposed method was applied to the determination of phenols in different water samples and a wastewater with recoveries in the range 90–99%. The greenness profile was established in accordance with the suggestions made by the NEMI (National Environmental Methods Index). The absence of PBT (persistent bioaccumulative and toxic chemicals) and corrosive reagents and a drastic reduction of generated wastes can be emphasized. [Copyright &y& Elsevier]

Abstract: This work demonstrates the extended application of microscale chemistry which has been used in the educational discipline to the real analytical purposes. Using Volhard''s titration for the determination of sodium chloride as a paradigm, the reaction was downscaled to less than 2mL conducted in commercially available microcentrifuge tubes and using micropipettes for the measurement and transfer of reagents. The equivalence point was determined spectrophotometrically on the microplates which quickened the multi-sample measurements. After the validation and evaluation with bulk and dosage forms, the downsized method showed good accuracy comparable to the British Pharmacopeial macroscale method and gave satisfactory precision (intra-day, inter-day, inter-analyst and inter-equipment) with the relative standard deviation of less than 0.5%. Interestingly, the amount of nitric acid, silver nitrate, ferric alum and ammonium thiocyanate consumed in the miniaturized titration was reduced by the factors of 25, 50, 50 and 215 times, respectively. The use of environmentally dangerous dibutyl phthalate was absolutely eliminated in the proposed method. Furthermore, the release of solid waste silver chloride was drastically reduced by about 25 folds. Therefore, microscale chemistry is an attractive, facile and powerful green strategy for the development of eco-friendly, safe, and cost-effective analytical methods suitable for a sustainable environment. [Copyright &y& Elsevier]

Direct matrix-assisted UV-photochemical/cold vapor generation for sample introduction was proposed for the determination of trace mercury in natural water by atomic fluorescence spectrometry. The optimal experimental conditions for the determination of mercury including sampling volume, UV irradiation time, carrier flow rate, pH, and the interference from coexisting metal ions were investigated in detail. Under the optimized experimental conditions, the limit of detection for total mercury was 0.03 ng mL-1. The accuracy of the proposed method was validated by analyzing two certified reference water samples with satisfactory analytical results. This method is simple, fast, green, highly selective, ultrasensitive, and yet inexpensive. [ABSTRACT FROM AUTHOR]

A 2-mm i.d. and 100-mm length electrophoretic microcolumn packed with quartz microparticles was proposed in this article. To investigate the microcolumn preparation, thermal effect and electrophoretic separation, tryptophan and tyrosine were used as the target analytes, and their separation parameters were optimized, including quartz microparticle size, buffer concentration and pH, and so on. With the 2-mm i.d. fused-silica microcolumn packed with 9 µm length uniform quartz microncrystals and the electrophoretic buffer solution of 0.75 mmol/L sodium tetraborate (pH 11.0), the thermal effect of the microcolumn electrophoresis was limited satisfactorily, and underivatized tryptophan and tyrosine were separated on baseline and detected at 224 nm by an ordinary spectrophotometer. The limits of detection for tryptophan and tyrosine were 0.018 and 0.080 µmol/L, respectively. The separation efficiency of tryptophan was 4.0 × 104 plates/m. The sample capacity of the electrophoretic microcolumn achieved 35 µL. Owing to low consumption of reagent solutions and organic solvents, the microcolumn electrophoresis belongs to a green analytical method. With the advantages of high detection sensitivity, large sample capacity, instrumental simplicity, and portability, it can be employed as one of the high-performance separation techniques for an in-situ and real-time electrokinetic flow analysis system. It can also be developed for preparative electrophoresis. [ABSTRACT FROM AUTHOR]

Abstract: A simple, inexpensive and reagent-less colorimetric micro flow analysis (μFA) system was implemented in a polymethyl methacrylate (PMMA) micro fluidic manifold. A T-shaped micro channel on a PMMA chip was fabricated by laser ablation and topped with molded polydimethylsiloxane (PDMS). The fabricated μFA system was integrated with the optical components as detector and applied to the determination of iron in water samples. It is based on the measurement of Fe(III)–nitroso-R salt complex at 720nm formed by the reaction between Fe(III) and nitroso-R salt in an acetate buffer solution pH 5. The proposed μFA consumed very small amount of reagent and sample, it released waste of less than 2.0mLh−1. The relative standard deviation (R.S.D.) was less than 2% (n =11) with the recovery of 98.7±0.12 (n =5). The linear range for the determination of iron in water samples was over the range of 0.05–4.0μgmL−1 with a correlation coefficient (r 2) of 0.9994. The limit of detection (3σ) and limit of quantitation (10σ) were 0.021μgmL−1 and 0.081μgmL−1, respectively with a sample throughput of 40h−1. [Copyright &y& Elsevier]

Two methodologies based on vibrational spectrometry—making use of Fourier transform infrared absorption (FTIR) and Raman spectrometry—were developed for iprodione determination in solid pesticide formulations. The FTIR procedure involved the extraction of iprodione by CHCl3, and the latter determination involved measuring the peak area between 1450 and 1440 cm−1, corrected using a horizontal baseline defined at 1481 cm−1. FT-Raman determination was performed directly on the powdered solid products, using standard chromatography glass vials as sample cells and measuring the Raman intensity between 1003 and 993 cm−1, with a two-point baseline correction established between 1012 and 981 cm−1. The sensitivities obtained were 0.319 area values g mg−1 for FTIR determination and 5.58 area values g g−1 for FT-Raman. The repeatabilities, taken to be the relative standard deviation of five independent measurements at 1.51 mg g−1 and 10.98% w/w concentration levels, were equal to 0.16% and 0.9% for FTIR and FT-Raman, respectively, and the limits of detection were 0.3 and 0.2% w/w (higher than those obtained for HPLC, 0.016% w/w). FTIR determination provided a sample frequency of 60 h−1, higher than those obtained for the Raman and reference chromatography methods (25 and 8.6 h−1, respectively). On the other hand, the new FT-Raman method eliminates reagent consumption and waste generation, and reduces the need for sample handling and the contact of operator with the pesticide. In spite of their lack of sensitivity, vibrational procedures can therefore provide viable environmentally friendly alternatives to laborious, time- and solvent-consuming reference chromatography methods for quality control in commercially available pesticide formulations. [ABSTRACT FROM AUTHOR]

Abstract: A green chromatographic analytical method for determination of Tartrazine, Brilliant Blue and Sunset Yellow in food samples is proposed. The method is based on the modification of a C18 column with a 0.25% (v/v) Triton X-100 aqueous solution at pH 7 and in the usage of the same surfactant solution as mobile phase without the presence of any organic solvent modifier. After the separation process on the chromatographic column, the colorants are detected at 430, 630 and 480nm, respectively. The chromatographic procedure yielded precise results and is able to run one sample in only 8min, consuming 15.0mg of Triton X-100 and 38.8mg of phosphate. When the flow rate of the mobile phase is 1mlmin−1 the retention times are 2.1, 3.6 and 7.0min for Tartrazine, Brilliant Blue and Sunset Yellow, respectively; and all peak resolutions are ca. 2. The analytical curves present the following linear equations: area=7.44 105 +2.71 105 [Tartrazine] (R =0.998, n =7); area=1.09 105 +3.75 105 [Brilliant] (R =0.9995, n =7) and area=−7.34 104 +2.33 105 [Sunset] (R =0.998), n =7) and, the limits of detection for Tartrazine, Brilliant Blue and Sunset Yellow were estimated as 0.125, 0.080 and 0.143mgl−1. When the proposed method is applied to food samples analysis, precise results are obtained (R.S.D.<5%, n =3) and in agreement with those obtained by using the classical spectrophotometric method. The traditional usage of organic solvent as mobile phase in HPLC is not used here, which permits to classify the present method as green. [Copyright &y& Elsevier]

[Display omitted] • Novel green chromatographic method for the simultaneous determination of 5-fluorouracil and cisplatin. • Evaluation of the greenness profile using NEMI, GAPI, Eco-scale and AGREE tools. • Application of a newly developed HPLC method to evaluate the drug release of co-loaded 5-fluorouracil and cisplatin films. The combination of 5-fluorouracil (5-FU) and cisplatin (Cis) has been used for the treatment of many cancers. The combination demonstrates synergy and improved clinical outcomes encouraging developing a formulation with both drugs. An analytical procedure is essential for formulation studies; however, no method has been reported for the concurrent determination and quantification of both 5-FU and Cis to date. A novel, simple, accurate, and precise HPLC method was developed using a C 18 column (250 mm × 4.6 mm, 5 µm) and mobile phase composed of 0.5 mM sodium dodecyl sulfate: methanol (98:2, v/v), adjusted to pH 2.5 with phosphoric acid. A flow rate of 0.5 mL/min was applied and a photodiode array was utilized for detection and the retention times were 9.89 min (265 nm) for 5-FU and 5.36 min (210 nm) for Cis. Validation procedures were performed, and the method was found to be linear at ranges of 0.9–60.0 µg/mL for 5-FU and 6.0–60.0 µg/mL for Cis. The limits of detection (LOD) and quantitation (LOQ) were 0.10 and 0.25 µg/mL for 5-FU and 2.00 and 4.00 µg/mL for Cis, respectively. Other parameters such as precision, selectivity, robustness, and stability results were within acceptable limits. The method was applied to a model co-eluting film and its release profile was studied. Additionally, the method's greenness was evaluated by four assessment tools namely the national environmental method index (NEMI), analytical eco scale assessment (ESA), green analytical procedure index (GAPI), and Analytical GREEnness Metric Approach and Software (AGREE). The results demonstrated compliance with green analytical chemistry (GAC) practices. This research acts as a step towards further investigation of drug stability under different stress conditions and quantification of the intact drugs in presence of their degradation products. [ABSTRACT FROM AUTHOR]

An analytical method for the quantification of total Hg and CH 3 Hg+ in biological tissues (fish, mushroom) and water sediment was developed based on small-sized electrothermal vaporization capacitively coupled plasma microtorch optical emission spectrometry using a low-resolution microspectrometer as detector. Sample preparation was carried out according to the procedure recommended by JRC Technical Report of European Commission for the determination of CH 3 Hg+ in seafood and adapted by us for lower consumption of reagents. Amounts of 0.1 – 0.5 g sample were subjected to extraction in 5 ml of 47% HBr then CH 3 Hg+ was extracted in 2 × 1 ml toluene and back-extracted in 2 ml aqueous solution of 1% l -cysteine. Total Hg/CH 3 Hg+ were quantified in 10 μl of acidic extract/ l -cysteine solution after electrothermal vaporization and measurement of 253.652 nm Hg signal in the episodic emission spectra. Under the optimal working conditions of system (70 °C sample drying, 1300 °C sample vaporization, 10 W plasma power and 150 ml min−1 Ar flow) the limits of detection were 7.0 μg kg−1 total Hg and 3.5 μg kg−1 CH 3 Hg+. Comparison of slopes in external calibration and standard addition procedure revealed the lack of non-spectral interferences of multimineral matrix, so that the calibration against Hg2+ standards was adopted. Pooled recovery of total mercury/methylmercury was 101 ± 7%/100 ± 7%, while precision assessed from measurements of real samples was in the range 1.6-9.6%/2.7-12.8%. The proposed method validated according to Eurachem Guide 2014 is selective and complies with demands in European legislation (Decisions 657/2002; 333/2007; 836/2011) and Association of Official Analytical Chemists Guide in terms of performances for food control. The method displays a high degree of greenness by circumventing cold vapor generation, use of small amounts of reagents and full-miniaturized instrumentation resulting in low analytical costs without reducing results quality. Besides, the method is simple and rapid, since it uses external calibration curves prepared from Hg2+standard solutions both for total Hg and CH 3 Hg+ determination. Image 1 • Total Hg and CH 3 Hg+ were directly quantified in biological samples and water sediments. • Quantification is based on external calibration using Hg2+ standards. • The method is free from non-spectral interferences and complies with GAC practice. • Method validation proved compliance with EU legislation relative to food control. [ABSTRACT FROM AUTHOR]

Chlorhexidine (CHX) is an antiseptic and disinfectant used in several antimicrobial preparations. In the current study an environmentally friendly ISE-potentiometric method was developed for the determination of CHX, measurements were carried out directly in the aqueous solution of the sample without pretreatment. Four PVC-membranes were fabricated using dioctylphthalate as a solvent mediator along with different cation exchangers, namely; sodium tetraphenylborate, sodium phosphotungstate tribasic, sodium phosphomolybdate and ammonium reineckate. Responses were compared and that containing ammonium reineckate illustrated the best near-Nernstian slope through a wide linear range (3.85 × 10−6–1 × 10−3 M). The sensor was able to determine CHX in colored and turbid solutions without prior extraction, pretreatment, filtration or derivatization steps. This method enabled in-site stability study without interference of para-chloroaniline (PCA) the most common and carcinogenic degradation product by monitoring the degradation kinetics of CHX at different pH values (3.5, 4.0 and 5.0). The sensor was able to provide a reliable in-line monitoring of the process without the need for frequent sample withdrawal at time intervals or sample pretreatment steps which saved time. Sensor response characteristics were calculated according to the IUPAC recommendations and the method was validated as per the ICH recommendations. The proposed method provided a green eco-friendly method that saves cost, time and effort, and consumes the least amount of chemicals. • Analysis of Chlorhexidine is of great impact in health care formulations. • Development of a relatively greener eco-friendly potentiometric method. • In-line monitoring of chlorhexidine kinetic study. • Stability indicating assay method for chlorhexidine. • Determination of chlorhexidine in pure form and in cosmetic formulations. [ABSTRACT FROM AUTHOR]