Analytical Eco-Scale Research Articles

Eco-Friendly Voltammetric Analysis of Flibanserin with Electropolymerized β-Cyclodextrin on Carbon Sensors

This study developed a cost-effective method to determine flibanserin (FLN) using a screen-printed carbon electrode modified with β-Cyclodextrin polymer (SPCE/β-CD). The electrode was modified in Britton-Robinson buffer at pH 5.0 to enhance FLN’s electrochemical oxidation, with cyclic and differential pulse voltammetry used for detection. Characterization techniques included energy-dispersive X-ray analysis, scanning electron microscopy, and Fourier transform infrared spectroscopy. The method showed a linear response to FLN concentrations ranging from 5.2 to 80.0 ng ml−1, with a detection limit of 0.004 μM and a quantitation limit of 0.014 μM. The modified electrode demonstrated good sensitivity, reproducibility, and was applied successfully to FLN analysis in spiked human serum and urine samples. An environmental impact assessment was conducted using the Green Analytical Procedure Index, which evaluates the green characteristics of the entire analytical methodology from sample collection to final determination. Additionally, the Analytical Eco-Scale, which assesses the use of organic preparations, procedures, and instruments, demonstrated a favorable green analysis profile. This modified electrode provides a convenient, cost-effective, and eco-friendly approach for determining flibanserin in various matrices.

Application of new green evaluation tools to assess the environmental impact of analytical procedures based on solid phase microextraction techniques

In this comparative study, four green evaluation tools, blue applicability grade index (BAGI), Analytical GREEnness (AGREE), Green Analytical Procedure Index (GAPI), and Analytical Eco-Scale were evaluated to assess 16 selected analytical methods including fiber-solid phase microextraction, stir bar sorptive extraction, and thin film microextraction joint to gas and liquid chromatographic as well as spectrofluorimetry techniques. The required parameters and data were extracted from the selected articles and calculations were performed based on the unique evaluation protocol of each tool. A uniform approach was applied in calculations and evaluations. A comparison of selected methods was done by determining the factors affecting greenness. High energy consumption, organic solvents, waste generation, analysis throughput, and the number of determined analytes, are among the crucial parameters that require improvement in the selected methods. The results show that using more than one evaluation tool in evaluating the greenness of analytical methods is very effective in obtaining synergistic results and increasing the understanding of the greenness of analytical methods.

Sodium salicylate as a green fluorescent probe for ultrasensitive determination of vonoprazan fumarate via fluorescence switch off strategy; greenness assessment

A green, simple and sensitive spectrofluorometric approach for determining vonoprazan fumarate in bulk and pharmaceutical dosage form by turning off the fluorescence of sodium salicylate is developed. The addition of vonoprazan fumarate reduced linearly the fluorescence intensity of 0.4 mM sodium salicylate at λem 408 nm and at λex 330 nm. The approach was found to be linear in the 50.0–3000.0 ng/mL range. The limits of detection and quantification were 10.97 and 33.23 ng/mL, respectively. The presented method proved its suitability in determination of vonoprazan fumarate in its pure and pharmaceutical dosage form. This method employs water as the exclusive solvent and utilizes safe reagents, evaluated using the Analytical Eco Scale, Green Analytical Procedure Index (GAPI), and carbon footprint. In contrast, previous methods relied on toxic reagents and required extended heating times, resulting in higher environmental impact. The novel method not only enhances analytical efficiency but also aligns with green chemistry principles, offering a sustainable solution for routine pharmaceutical analysis.

Greener method proposal for the determination of phenolic compounds and coumarins in aged sugarcane spirits using green bio-based solvents in HPLC-DAD-FLD system

High Performance Liquid Chromatography (HPLC) has been the most used analytical technique for analyzing phenolic compounds and coumarins in aged sugarcane spirit samples. It requires a significant amount of organic solvents, often toxic, as the mobile phase. The use of green bio-based solvents is a good alternative in the implementing more eco-friendly methods. Therefore, this work aims to propose a greener chromatographic method for the determination of phenolic compounds and coumarins in sugarcane spirit samples aged in different woods, using bio-based organic solvents (ethanol and acetic acid) in HPLC system with diode array and fluorescence detectors. Different metric tools (AGREE, ComplexMoGAPI, BAGI and Analytical Eco-scale) were used to evaluate the greenness of the analytical method. The proposed method was rigorously validated: linearity (R2 ≥ 0.9901); LOD (0.05 to 0.55 mg l-1); LOQ (0.25 to 5.00 mg l-1); precision (0.13 % ≤ RSD ≤ 18.6 %). The concentrations of total phenolic compounds and coumarins were up to 7.22 mg l-1. The sugarcane spirit aged in umburana presented the highest concentration of total phenolic compounds and coumarins with emphasis on trans-cinnamic acid (4.74 ± 0.01 mg l-1) and catechin (1.22 ± 0.02 mg l-1). All samples presented coumarin concentrations (<5.00 mg l-1) within the limit acceptable by legislation (10 mg l-1). The AGREE score (0.72) showed that the proposed method was greener and sustainable compared to other methods. The application of new mobile phase using green bio-based solvents proved to be advantageous from a Green Analytical Chemistry point of view.

Application of a novel deep eutectic solvent as an eco-friendly medium for green extraction of cadmium from herbal medicines

In this research, hydrophobic DESs were successfully prepared using components with hydrophobic and sulfydryl group, which were applied to develop a green and eco-friendly method to extract and detect the cadmium (Cd) in herbal medicine (HM). The basic properties of the DESs were studied, which showed good hydrophobicity, low density and sufficient absorption capacity. In extraction process, the extraction efficiency (EE) of Cd employing proposed process ranged from 89.12 %∼94.59 % and the maximal enrichment factor (EF) was 46.85. The DES based method demonstrated a good linear response in the range of 1 ∼ 50 µg·L-1 with a detection limit (LOD) of 0.29 μg L-1, which was detected by Inductively coupled plasma mass spectrometry (ICP-MS). Additionally, the accuracy of method (as recoveries %) was obtained with the recoveries ranging from 98.38 %∼105.48 %. The extraction process was also compared with microwave digestion (MD) method and showed basically equivalent effect with good propensity to enrichment. The mechanism was explored by DFT calculation to reveal the interaction of extraction process. The greenness of the proposed method was also evaluated using the Green Analytical Procedure Index (GAPI) and Analytical Eco-Scale (AES), which indicated excellent environmental protection. This study successfully prepared novel DESs and established an eco-friendly and effective analytical process integrating adsorption, collection, separation and detection for the detection of heavy metals in HM, and the DESs were contributed to the first three parts as a multifunctional role. The absorption mechanism related to the formation of molecular complexes in quantum chemistry perspective, which were attribute to the electrostatic attraction and H+ exchange between Cd and adsorbent. This method showed vast potential in heavy metal research involving complex matrices such as HM and its processed products, and the proposed process provides the way for a greener alternative for Cd extraction rather than conventional polluting processes.

Green highly sensitive and selective spectroscopic detection of guaifenesin in multiple dosage forms and spiked human plasma

Guaifenesin (GUA) is determined in dosage forms and plasma using two methods. The spectrofluorimetric technique relies on the measurement of native fluorescence intensity at 302 nm upon excitation wavelength “223 nm”. The method was validated according to ICH and FDA guidelines. A concentration range of 0.1–1.1 μg/mL was used, with limit of detection (LOD) and quantification (LOQ) values 0.03 and 0.08 µg/mL, respectively. This method was used to measure GUA in tablets and plasma, with %recovery of 100.44% ± 0.037 and 101.03% ± 0.751. Furthermore, multivariate chemometric-assisted spectrophotometric methods are used for the determination of GUA, paracetamol (PARA), oxomemazine (OXO), and sodium benzoate (SB) in their lab mixtures. The concentration ranges of 2.0–10.0, 4.0–16.0, 2.0–10.0, and 3.0–10.0 µg/mL for OXO, GUA, PARA, and SB; respectively, were used. LOD and LOQ were 0.33, 0.68, 0.28, and 0.29 µg/mL, and 1.00, 2.06, 0.84, and 0.87 µg/mL for PARA, GUA, OXO, and SB. For the suppository application, the partial least square (PLS) model was used with %recovery 98.49% ± 0.5, 98.51% ± 0.64, 100.21% ± 0.36 & 98.13% ± 0.51, although the multivariate curve resolution alternating least-squares (MCR-ALS) model was used with %recovery 101.39 ± 0.45, 99.19 ± 0.2, 100.24 ± 0.12, and 98.61 ± 0.32 for OXO, GUA, PARA, and SB. Analytical Eco-scale and Analytical Greenness Assessment were used to assess the greenness level of our techniques.

Eco-friendly quantification of hydrogen peroxide in milk using green-synthesized iron nanoenzymes

In this work, iron nanoparticles (FeNPs) were synthesized by a green method using Eucalyptus grandis leaf extract as a reducing and stabilizing agent. The FeNPs were employed as nanoenzymes for oxidizing o-phenylenediamine, enabling the development of a spectrophotometric method to detect and quantify hydrogen peroxide in milk. The method was validated according to the validation protocols. The analytical curve (8.97–112.16 µmol L−1) for UHT (Ultra High Temperature) whole milk showed a good linear fit. The limits of detection and quantification were 2.96 µmol L−1 and 9.89 µmol L−1, respectively. The method demonstrated an accuracy ranging from 85.1 % to 102.8 %, with a repeatability of ≤ 3.9 % and an intermediate precision of ≤ 7.5 %. The method proved its effectiveness on various types of milk and was compared with other conventional methods traditionally applied to milk analysis. The novelty of the method lies in the use of FeNPs synthesized through a bioinspired process using plant extract, employed for the first time in the detection of H2O2 in milk, a highly complex matrix. The advantages of the analytical method include the use of a small sample and reagent volumes. The ecological aspects of the developed procedure were evaluated using the Analytical Eco-scale protocols, resulting in a score of 77, classified as an excellent green analysis, confirming it as an environmentally friendly method.

Efficient and environmentally friendly spectrofluorimetric determination of cariprazine: An analytical and green chemistry approach.

Cariprazine represents a new generation of antipsychotic medication, characterized by its heightened affinity for the D3 receptor. It has recently obtained approval as an adjunctive treatment option for patients diagnosed with major depressive disorder. In this study, a novel approach utilizing fluorescence spectroscopy was developed to analyze cariprazine. The methodology involves the transformation of cariprazine into a fluorescent compound by means of chemical derivatization with 4-chloro-7-nitrobenzo-2-oxa-1,3-diazole (NBD-Cl). Following excitation at 470 nm, the fluorescent derivative displayed peak fluorescence emission at 550 nm. The factors influencing the derivatization process were optimized. Upon reaching the optimal reaction conditions, a linear correlation (r2=0.9995) was observed between the fluorescence intensity and concentrations of cariprazine ranging from 20 to 400 ng/ml. Detection and quantitation limits were determined to be 5.85 and 17.74 ng/ml, respectively. The approach was accurate and precise, with percent recovery values ranging from 98.14% to 99.91% and relative standard deviations of less than 2%. Application of the method to the analysis of cariprazine in bulk and commercial capsules forms yielded accurate results. Moreover, adherence to environmentally friendly analytical practices was evident through alignment with the principles of green analysis, as demonstrated by the analytical eco-scale, AGREE, and GAPI greenness assessment tools.

Layered double hydroxide/conductive polymer nanocomposites: Toward multifunctional biocompatible nanoadsorbents for wastewater treatment applications

ABSTRACT Layered double hydroxide (LDH)/conductive polymer nanocomposites combine the promising adsorption capabilities of 2D layered nanomaterials and the electric properties of conductive polymers, resulting in multifunctional adsorbents for wastewater treatment. In this work, a simple in situ polymerization of aniline was conducted in the presence of Zn-Fe LDH to synthesize a Zn-Fe LDH/PANI nanocomposite, which was characterized by XRD, FTIR, SEM, and BET. The composite showed a particle-like morphology with a size of 30–60 nm and a BET surface area of 23.27 m2/g and was used as an adsorbent for carbamazepine (CBZ). Zn-Fe LDH/PANI removed 98% of CBZ at pH 7, 0.2 g/L, and 40 mg/L CBZ. For biocompatibility, acute toxicity was assessed in vivo for ten days using male albino rats, and probit analysis (after 2, 6, and 24 hours) was used to determine the LD0, LD20, LD50, LD90, and LD100 values, which were calculated to be 890, 1051, 3188, 6371, and 11,300, respectively. During this time, the rats were weighed, and other observations were made, including mortality, behavior, injuries, and any symptoms of toxicity or side effects. Histopathological examination of organs such as the liver, kidney, brain, skin, intestine, and cecum for any pathological alterations was performed. Two green metrics were applied, the Analytical Eco-scale and the Analytical GREEness Calculator (AGREE).

Evaluation of analytical greenness metric for an eco-friendly method developed through the integration of green chemistry and quality-by-design for the simultaneous determination of Nebivolol hydrochloride, Telmisartan, Valsartan, and Amlodipine besylate

In recent years, the field of analytical chemistry has witnessed a notable shift towards the adoption of greener chromatographic methods, aiming to minimize the environmental impact. An effective strategy involves substituting conventional harmful organic solvents with environmentally friendly alternatives, reducing the use of hazardous chemicals that contribute to environmental concerns. However, separating drug substances without the use of buffers and organic solvents presence is a big challenge. To overcome this challenge, a combination of quality-by-design (QbD) and green analytical chemistry (GAC) was employed in this study for method development. A high-performance liquid chromatography (HPLC) method was successfully developed and validated for the simultaneous determination of Nebivolol hydrochloride, Telmisartan, Valsartan, and Amlodipine besylate. The method utilized a mobile phase composed of a mixture of 0.1 % formic acid in water (pH: 2.5) and ethanol. A regular octadecyl silica (ODS) column was employed, and UV detection at 220 nm was utilized. The method exhibited linearity within the concentration range of 25–75 μg/mL for Telmisartan and 150–450 μg/mL for Nebivolol Hydrochloride, Valsartan, and Amlodipine besylate and the correlation coefficient was greater than 0.999 for all the analytes. Limits of detection (LOD) and quantification (LOQ) were determined as 0.01 and 0.04 μg/mL for Telmisartan, 0.06 and 0.20 μg/mL for Nebivolol Hydrochloride, 0.08 and 0.25 μg/mL for Amlodipine besylate, and 0.14 and 0.46 μg/mL for Valsartan, respectively. The developed method underwent thorough validation, encompassing various parameters such as linearity, accuracy, precision, LOD, LOQ, robustness, and ruggedness. The mean recovery values were observed to range between 98.86 % and 99.89 %. The accuracy demonstrated was consistently above 98.98 % for both intra-day and inter-day precisions were with the relative standard deviations less than 2 %. To establish its robustness, a quality-by-design-based experimental design (DoE) approach was implemented. Additionally, the method's environmental friendliness was evaluated using the Analytical Greenness metric (AGREE) an analytical eco scale, both confirming its alignment with sustainable practices and reduced ecological impact. The sustainability of the solvent used in the current study was evaluated by Green Solvents Selecting Tool (GSST) Further, the developed method greenness was evaluated with the green analytical tools such as Analytical method greenness score (AMGS) and using the recently released White Analytical Chemistry (WAC) using RGB assessment tool. By employing this greener approach to chromatography method, this study contributes to the ongoing efforts in analytical chemistry to promote sustainable practices and minimize the environmental footprint of analytical methods.

Green method for quantification of lavender and sweet orange essential oils in blends by synchronous fluorescence first derivative

A simple green method for the quantification of sweet orange and lavender essential oils (EOs) content in blends was developed using synchronous fluorescence of the first derivative spectra and sample preparation by surfactant-free microemulsions (SFMEs). Excitation and emission wavelengths pairs (λex/λem) were determined for both EOs (at 336/436 nm for sweet orange and at 330/388 nm for lavender). Optimization was conducted to establish the condition to prepare the SFMEs systems: 50 μL of oily phase containing EO diluted in octan-1-ol (1:4, v/v), 2.0 mL of water and propan-1-ol up to 5.0 mL final volume. Different proportions of EO in the oily phase were evaluated for analytical curves construction. Synchronous fluorescence measurements were performed and the acquired data were corrected by inner filter effect. Considering the first derivative of the synchronous scanning, data were extracted at 316.8 nm (Δλ = 100 nm) and 352.0 nm (Δλ = 58 nm) for sweet orange and lavender EOs, respectively, with correlation coefficients above 0.99. Limits of quantification of 7.97 μg mL−1 and 65.80 μg mL−1 were obtained indicating that 0.46% of sweet orange and 3.69% of lavender EOs can be quantified in mixtures. Simulated blends (25:75%, 50:50% and 75:25%, volume proportions) were also evaluated with recoveries of 71.5 – 128.9% and coefficient of variation between 3.1% – 11.6%. Additionally, the method's greenness was evaluated through three green metrics (Analytical Eco-Scale, GAPI, and AGREE) with consistent results.

Greenness assessment and comparison of the developed and validated green HPLC-PDA, HPLC-FLD, and HPLC-ELSD methods for the determination of melatonin in various products using analytical eco-scale, NEMI, GAPI, and AGREE greenness metric tools

Melatonin, recognized as the hormone governing sleep, is an endogenous hormone synthesized by the pineal gland situated in the brain. It orchestrates the sleep-wake cycle and fosters optimal circadian rhythm. Owing to its manifold metabolic advantages, particularly in the realm of circadian rhythm regulation, melatonin finds extensive application in various supplementary formulations. The elimination of hazardous chemical waste in common chromatographic separations has become an essential issue. We present a green, eco-friendly, novel, sensitive, rapid, robust, and three simple methods including the HPLC-PDA, HPLC-FLD, and HPLC-ELSD approach for the simultaneous determination of MEL in various products. The mobile phase of all the HPLC methods consists of only water and an ethanol mixture and is free from any toxic solvents. All the separations were made on a C18 column (5 μm particle size, 250 mm x 4.6 mm id.). LODs were found to be as 1.20 ng mL−1, 0.02 ng mL−1, 1.26 µg mL−1, and LOQs 4.00 ng mL−1, 0.07 ng mL−1, 4.21 µg mL−1 for PDA, FLD and ELSD, respectively. The recovery results were found to be within 98.58–102.35 %. Moreover, the greenness assessment of all the HPLC methods was assessed using the Analytical Eco-scale, NEMI, AGREE, and GAPI. The developed methods have been demonstrated to be applicable in routine analyses for the determination of melatonin in various preparations.

Smart Chemometric‑Assisted Spectrophotometric Approaches for Simultaneous Quantification of Tertiary Combination Recommended for COVID-19 Supportive Treatments with Their Greenness Assessment.

There is an increasing interest of scientific community in developing innovative methodologies for their analysis needs within green analytical chemistry framework. UV spectrophotometry is one of the most promising eco-friendly methods, which is integrated with advanced chemometric tools to enhance the selectivity of the analysis of complex mixtures with severe overlapped signals. Simultaneous determination of a triple-combination of pseudoephedrine hydrochloride (PSE), carbinoxamine maleate (CRX), and paracetamol (PAR) using an artificial intelligence system and multivariate calibration methods. This combination is recently recommended for COVID-19 home-treated patients as part of a symptomatic treatment. Namely, the suggested models are: Artificial Neural Networks, Partial Least Squares, and Principal Component Regression. The proposed algorithms were optimized and developed with the aid of a five-level, three-factor experimental design. The investigated methods were applied over the concentration range of 100-180 μg/mL, 18-16 μg/mL, and 4-12 μg/mL for PSE, CRX, and PAR, respectively. The models validation results demonstrated excellent recoveries (around 98 to 102%), signaling the approaches outstanding resolution capacity for the cited compounds in the presence of common excipients. The outcomes of the studied methods were statistically compared to the official approaches, and no significant difference was found. The suggested models were efficiently employed to determine the selected drugs in their combined tablets without any initial separation steps. The impact of these methods on the environment was evaluated via greenness tools, namely; National Environmental Method Index, Raynie and Driver's green assessment method, analytical Eco-Scale, Green Analytical Procedure Index, and Analytical Greenness Metric. Green chemometric quality assessment of PSE, CRX, and PAR in their pure and pharmaceutical dosage forms. The established approaches are innovative, sustainable, smart, fast, selective, and cost-effective. These models are potential green nominees for routine analysis of the investigated mixture in quality control laboratories.

Rapid and ecofriendly ultra performance liquid chromatographic analytical methodology for the simultaneous determination of four drugs included in COVID-19 treatment protocol

The global spread of COVID-19 disease has increased the demand for new therapeutic approaches. The clinical studies revealed that remdesivir and molnupiravir have been effective against COVID-19. Remdesivir (REM) is the first FDA-approved antiviral drug for COVID-19, while molnupiravir is the first oral antiviral drug for SARS-CoV-2 infections. In addition to antivirals, anticoagulants such as apixaban (APX) and antibiotics such as levofloxacin (LVF) are also included in the treatment protocols. This study suggests and validates a rapid and selective method for the determination of the four drugs involved in the COVID-19 treatment protocol. The simultaneous separation and determination of REM, MLP, LVF, and APX in human plasma were achieved using UPLC with a fluorophenyl column and a mobile phase composed of acetonitrile and water acidified with formic acid (pH = 3) in the ratio of 45: 55, v/v, at a flow rate of 0.1 mL/min. The PDA detector was adjusted at 254 nm. The method could simultaneously determine the four drugs in a single run in less than 6 min. The method exhibited linearity over the concentration ranges of 1.0–15.0 µg/mL, 0.1–5.0 µg/mL, 0.1–2.0 µg /mL, and 0.1–5.0 µg/mL, for LVF, MLP, APX and REM, respectively. The proposed method was validated following the International Council on Harmonization Q2(R1) guidelines and the findings were compared statistically to previously reported methods. The recovery rates of the drugs from spiked human plasma were satisfactory. The greenness of the suggested method was evaluated using three metrics, namely, Analytical Eco-scale, Green Analytical Procedure Index (GAPI) metric, and the Analytical GREEnness measure approach (AGREE).

Development of an eco-friendly fluorescent probe for mefenamic acid sensing in pharmaceuticals and biofluids.

Mefenamic acid, renowned for its analgesic properties, stands as a reliable choice for alleviating mild to moderate pain. However, its versatility extends beyond pain relief, with ongoing research unveiling its promising therapeutic potential across diverse domains. A straightforward, environmentally friendly, and sensitive spectrofluorometric technique has been developed for the precise quantification of the analgesic medication, mefenamic acid. This method relies on the immediate reduction of fluorescence emitted by a probe upon interaction with varying concentrations of the drug. The fluorescent probe utilized, N-phenyl-1-naphthylamine (NPNA), was synthesized in a single step, and the fluorescence intensities were measured at 480 nm using synchronous fluorescence spectroscopy with a wavelength difference of 200 nm. Temperature variations and lifetime studies indicated that the quenching process was static. The calibration curve exhibited linearity within the concentration range of 0.50-9.00 μg/mL, with a detection limit of 60.00 ng/mL. Various experimental parameters affecting the quenching process were meticulously examined and optimized. The proposed technique was successfully applied to determine mefenamic acid in pharmaceutical formulations, plasma, and urine, yielding excellent recoveries ranging from 98% to 100.5%. The greenness of the developed method was evaluated using three metrics: the Analytical Eco-scale, AGREE, and the Green Analytical Procedure Index.

An eco-friendly first and second derivative synchronous spectrofluorimetry for quantification of florfenicol in presence of its different degradation products. Application to kinetic stability study.

Two rapid, simple, sensitive and selective derivative spectrofluorimetric methods (first and second derivative synchronous spectrofluorimetric (FDSFS and SDSFS) procedures) have been developed for the analysis of florfenicol in the presence of its various degradation products. FDSFS was applied to assay the drug in the presence of its alkaline, oxidative and photolytic degradation products while SDSFS was used to quantify it in the presence of its acidic degradation product. These methods permitted quantification of florfenicol at corresponding λ Em of 288, 287, 279 and 284 nm without interferences from any of its degradation products. Full validation procedures were applied to the suggested method according to International Conference of Harmonization guidelines. Moreover, different degradation kinetic parameters were calculated such as half-life (t 1/2), degradation rate constant (K) and activation energy (E a). Using the analytical eco-scale, green analytical procedure index and analytical greenness metric approach AGREE as greenness assessment tools, the proposed method was found to be environmentally friendly.

QbD green analytical procedure for the quantification of tolvaptan by utilizing stability indicating UHPLC method

For the first time a new QbD-assisted green stability indicating ultra-high-performance liquid chromatography (UHPLC) method was developed and validated for quantifying Tolvaptan. The method is simple, quick, cost-effective, and stable, and it was used to formulate a quality target product profile (QTPP) with strategically defined critical analytical attributes (CAAs) to meet specific criteria. Chromatographic separation was undertaken using a 10 cm long column of ACE excel super C18 with an interior diameter of 2.1 mm and particle size of 1.7 µm. The analysis was performed under controlled conditions at 25 ℃ with the mobile phase flowing at a rate of 0.2 mL/min and detection occurring at 220 nm. Injected 3 µL of standard by using an isocratic mobile phase system consisting of acetonitrile and water in a 95:5 v/v ratio. The diluents, prepared by mixing acetonitrile with water at a 90:10 volumetric ratio, were utilized. The analyte’s retention time was determined to be 1.63 min. The developed method provided reliable results with accuracy exceeding 99% and a correlation coefficient exceeding 0.999 ranged between 10 and 150 µg/mL across the range for LOQ—150% levels. Notably, during forced degradation testing, Tolvaptan exhibited susceptibility to acidic hydrolysis. The method effectively separated degradation products during stress testing, demonstrating its stability-indicating status. Environmental sustainability assessment of the developed method was conducted through the investigation of various indicators of Complex GAPI, Analytical Eco scale and Analytical GREEness and it was concluded the optimized method aligns with environmentally friendly practices.

Ecofriendly UPLC-MS/MS method for simultaneous assay of veterinary drugs residues; erythromycin, sulfadiazine and trimethoprim in edible chicken tissues, evaluation of method greenness and whiteness

Antibiotics are the key veterinary drugs used in animal food production. The uncontrolled widespread use of antibiotics may lead to the accumulation of their residues in foodstuff such as milk, eggs, meat and muscles. An Ultra-performance liquid chromatography-tandem mass spectrometry (UPLC/MS/MS) method was developed for simultaneous determination of triple combination of erythromycin thiocyanate (ERY), sulfadiazine sodium (SFD) and trimethoprim (TMP) in their dosage form and in different chicken tissues including muscles and liver samples. A Simple extraction and cleaning up procedure was applied using 0.1 N EDTA and methanol to remove the interfering substances and hence increase the efficiency of chromatographic separation. Moreover, separation was performed within 1.2 min on Agilent Poroshell 123EC-C18 column using a mobile phase mixture of methanol: water (90:10, v/v), at a flow rate of 0.5 mL/min using quadrupole tandem mass spectrometer detector. The method was validated according to Food and Drug Administration (FDA) guidelines and linearity was achieved in the range of 2.5–1000 ng/mL for ERY and TMP and in the range of for 5–2000 ng/mL for SFD using tamsulosin (TAM) as an internal standard. All the validation results were within the acceptable ranges. Moreover, Three green metric systems including Green Analytical Procedure Index (GAPI), Analytical Eco-Scale and Analytical GREEnness (AGREE) were used to assess the greenness of the developed method. As well as, the novel blue applicability grade index (BAGI) tool was applied to evaluate the practicality of the method. Results of these tools proved the low environmental impact of the method regarding solvent consumption, analysis time, amount of sample needed, sample treatment procedure, and waste product. The developed method has the privilege of high sensitivity and selectivity as well as short analysis time; hence it can be used to test the presence of the residues of studied drugs in various marketed meat samples to assure human safety and maintain public health. Moreover, it is the first developed method for their analysis in liver samples.

Cutting-edge HPLC and MCR techniques for synchronically quantifying anticholinergic drugs in the presence of C12 and C14 homologs: Robust application to green and white chemistry.

Green and white chemistry are vital to revolutionizing the chemical industry through their unparalleled potential to enhance sustainability and efficiency. In this study, nine sustainability tools of both green and white metrics, including green analytical procedure index (GAPI), ComplexGAPI, analytical greenness, analytical greenness metric for sample preparation, Analytical Eco-Scale (ESA), analytical method greenness score, high-performance liquid chromatography- environmental assessment tool (HPLC-EAT), analytical method volume intensity, and blue applicability grade index (BAGI), have been developed for appraising environmental friendliness for both innovative and straightforward mean centering of ratio spectra (MCR) and reversed-phase high-performance liquid chromatography (RP-HPLC)strategies utilized for concurrent analysis and separation of cyclopentolate (CYC) and C12 and C14 homologs of benzalkonium chloride (BNZ) in pure and ophthalmic solution. The mobile phase, formed of buffer phosphate and acetonitrile (35:65, v/v), was adjusted to pH 6.3, and 215-nm UV detection was used. The experimental flow rate was 2.0 mL min-1, and the analytical column was L11 Inertsil Ph-3 (150 mm × 4.6 mm, 5 µm). All sequences were run at 25°C in the column oven. The MCR approach effectively resolved the drug's spectral overlapping. CYC and BNZ employed this approach at 227.5 and 220.4 nm, respectively. As part of the HPLC analysis, an isocratic method was employed with phosphate buffer and acetonitrile in the mobile phase at 35:65. A correlation coefficient greater than 0.999 was observed between the calibration curves for the HPLC and MCR methods in the ranges of 20-320 µg mL-1 and 5-30 µg mL-1 for all drugs. The technique yields excellent primary recovery rates, ranging from 97.2% to 100.5%. The recommended approach has been validated according to International Council for Harmonizationguidelines.

Chemical nature evolution of solid supports used in electromembrane extraction procedures: A comparative analysis based on metric tools

BackgroundIn recent decades, green chemistry has been focusing on the adaptation of different chemical methods towards environmental friendliness. Sample preparation procedures, which constitute a fundamental step in analytical methodology, have also been modified and implemented in this direction. In particular, electromembrane extraction (EME) procedures, which have traditionally used plastic supports, have been optimized towards greener approaches through the emergence of alternative materials. In this regard, biopolymer-based membranes (such as agarose or chitosan) have become versatile and very promising substitutes to perform these processes. ResultsDifferent green metric tools (Analytical Eco-Scale, ComplexGAPI and AGREEprep have been applied to study the evolution of solid supports used in EME from nanostructured tissues and polymer inclusion membranes to agar films and chitosan flat membranes. The main goal is to evaluate the usage of these new biomaterials in the analytical procedure to quantify their environmental impact in the frame of Green Analytical Chemistry (GAC). In addition, both RGB model and BAGI metrics have been employed to study the sustainability of the whole procedure, including not only greenness, but also analytical performance and feasibility aspects. Results obtained after the performance of the mentioned metrics have demonstrated that the most efficient and environmentally friendly analytical methods are based on the use of chitosan supports. This improvement is mainly due to the chemical nature of this biopolymer as well as to the removal of organic solvents. SignificanceThis work highlights the advantages of biodegradable materials employment in EME procedures to achieve green analytical methodologies. These materials also contribute to raise the figure of merits regarding to the quantification parameters in a wide range of applications compared to classical supports employed in EME, thus enhancing sustainability of procedures.