Hasse diagram as a green analytical metrics tool: ranking of methods for benzo[a]pyrene determination in sediments

Utility and greenness appraisal of nuclear magnetic resonance for sustainable simultaneous determination of three 1,4-benzodiazepines and their main impurity 2-amino-5-chlorobenzophenone

A robust, stability-indicating, and eco-friendly proton nuclear magnetic resonance (1H-qNMR) method was developed for the concurrent determination of three 1,4-benzodiazepines (BDZs), namely diazepam (DZP), alprazolam (ALP), and chlordiazepoxide (CDP) and their common impurity, synthesis precursor, and degradation product; 2-amino-5-chlorobenzophenone (ACB). In the present method, a novel approach was developed for composing a green and cost-efficient solvent system as an alternative to the common NMR organic solvents utilizing 0.3 M sodium dodecyl sulfate prepared in deuterated water. The conducted method is characterized by simplicity with no need for sample pretreatment or labeling. Phloroglucinol was used as an internal standard. The chosen signals for the determinations of ALP, CDP, DZP and ACB were at 2.35 ppm (singlet), 2.84 ppm (singlet), 3.11 ppm (singlet), and 6.90 ppm (doublet of doublet), respectively. The proposed method possessed linearity over the concentration range of 0.25-15.0 mg ml-1 for DZP, ALP, CDP and of 0.5-25.0 mg ml-1 for ACB with LOD values of 0.06, 0.03, 0.07 and 0.16 mg ml-1 respectively, and LOQ values of 0.18, 0.09, 0.21 and 0.49 mg ml-1, respectively. Accuracy of the method was evidenced by excellent recovery% (99.57-99.90%) and small standard deviation (≥ 1.10) for the three analyzed drugs. Intra- and inter-day precision were determined with coefficient of variation ranging from 0.12 to 1.14 and from 0.72 to 1.67, respectively. For the studied compounds, appraisal of the method greenness was achieved via four approaches: Analytical Eco-Scale, Green Analytical Procedure Index (GAPI), Analytical greenness metric (AGREE), and RGB Additive Color Model. The results proved that the proposed method has the privilege of being a green analytical method.

Modified QuEChERS Method for Extracting Thiamethoxam and Imidacloprid from Stingless Bees: Development, Application, and Green Metrics

In the present study, a method for the determination of residues of the neonicotinoid insecticides thiamethoxam and imidacloprid in the stingless bee Melipona scutellaris Latreille (1811) was optimized through a factorial design, tested using green metrics, and then applied to exposed bees. It combines the extraction with a modified quick, easy, cheap, effective, rugged, and safe method and the determination by liquid chromatography-tandem mass spectrometry analysis. Different parameters such as the mass of the sample, dispersive sorbents, and elution solvents were assessed. Method validation parameters were checked and include sensitivity, specificity, and linearity. The limit of quantification of 0.0025 μg g^-1 was obtained for both insecticides, where accuracy was 94%-100% with satisfactory intraday and interday precisions (relative standard deviation <10%). The qualified method was applied to orally and topically exposed bee samples, and the results indicated that it is suitable for the determination and quantification of neonicotinoid pesticide residues in this species. Moreover, green analytical metrics like the National Environmental Methods Index, Eco Scale score, high-performance liquid chromatography with an environmental assessment tool (HPLC-EAT), waste generation, and amount of sample were compared with methods described in the literature involving neonicotinoid analysis in honeybees. As a result, the present study displayed the highest Eco Scale score and HPLC-EAT score and the second smallest amount of sample and waste generated. Thus, the method meets green analytical metrics more than other methods. In this sense, besides the application, the multicriteria decision analysis tool employed suggests that this is a good option as a green analytical method. Environ Toxicol Chem 2022;41:2365-2374. © 2022 SETAC.

Taguchi Approach for Optimization of a Green Quantitative 1H-NMR Practice for Characterization of Levetiracetam and Brivaracetam in Pharmaceuticals

Background

Recently, quantitative nuclear magnetic resonance (qNMR) competes with separation techniques such as high performance liquid chromatography (HPLC) and capillary electrophoresis for quantification purposes when dealing with molecules that lack a chromophore.

Objective

The advantages of the proton nuclear magnetic resonance spectroscopy as a revolutionary quantitative analysis method were exploited aimed at simple and green assessment of two racetams, namely levetiracetam (LEV) and brivaracetam (BRV), as a new family of antiepileptic medications with a unique mechanism of action. The developed technique was effectively used to determine LEV in Keppra tablets and BRV in laboratory-prepared tablets without interfering with the ordinarily suspected excipients.

Method

A Taguchi approach was applied as a powerful and user-friendly statistical technique for optimization of the qH1NMR experimental design for both drugs. The optimum acquisition conditions were number of scans 32, pulse angle 20°, and relaxation delay of 40 s for LEV and number of scans 128, pulse angle 90°, and relaxation delay of 1 s for BRV. NMR spectra were obtained by means of phloroglucinol as an internal standard and dimethyl sulfoxide-d6 as a solvent.

Results

The diagnostic doublet of doublet quantitative signals at 4.3 and at 4.2 ppm were chosen to estimate LEV and BRV, respectively. The recovery of both drugs was quantified through the range of 0.1–12 mg/mL. The limits of detection were 0.013, 0.0013 and the limits of quantitation were 0.04, 0.0039 mg/mL for LEV and BRV correspondingly.

Conclusions

The suggested technique was fully validated according to ICH guidelines and proved to be an eco-friendly practice by means of three different assessment tools, including the green analytical procedures index, national environmental methods index, and analytical eco-scale. qH1NMR should be considered a green alternative for quantification and quality control assessment of pharmaceuticals.

Highlights

This research represents the first simple, quick, and green alternative method for determination of both racetams in their pharmaceuticals.

Determination of Asenapine Maleate in Pharmaceutical and Biological Matrices: A Critical Review of Analytical Techniques over the Past Decade

Asenapine maleate is a second-generation atypical antipsychotic agent used in the treatment of schizophrenia, a neuropsychiatric disorder. It is available as a fast-dissolving sublingual tablet to avoid extensive first-pass metabolism with higher bioavailability as compared to oral formulations. Although, the established therapeutic solutions do not sufficiently satisfy the patient's safety and efficacy needs. Thus, the core research emphasis is to investigate strategies to produce novel formulations with enhanced safety and efficacy. This necessitates the development of robust, precise, and accurate methods for quantification of asenapine maleate in different sample matrices. Given the foregoing information, the current analysis concentrates on the different analytical techniques used to assess asenapine maleate in bulk, pharmaceutical formulations, and biological specimens. Reverse-phase HPLC coupled with UV detection is a majorly (nearly 50% of papers investigated) used technique for the estimation of asenapine maleate in formulations. On the other hand, for its quantification in the biological matrix, hyphenated techniques using mass spectrometry are widely used. This critical review reveals different analytical methodologies, including spectrophotometric, chromatographic, capillary electrophoresis techniques reported from 2011 to 2020, for the measurement of asenapine maleate in various sample matrices. The information presented in this review would be useful in future research for robust analytical method development for asenapine maleate utilizing a more scientific and risk-based approach. Also, it would aid to minimize analytical failure as well as method fine-tuning throughout the product life cycle. Further, this review may also direct scientists toward the development of methodologies for green research.

Occurrence, distribution, and risk of organochlorine pesticides in food and greenness assessment of method

Organochlorine pesticides (OCPs) have been used globally to boost food production. Although banned, due to their prolonged toxic effects but their residue still impacts the quality of primary and processed agricultural products. This study assesses the levels of residual OCPs (α,β,δ-HCH, heptachlor, heptachlor epoxide, chlordane, methoxychlor, aldrin, dieldrin, endrin, endrin aldehyde, endrin ketone, endosulfan, endosulfan sulfate, 1,1-dichloro-2,2-bis(p-chlorophenyl)ethane (DDD), 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene (DDE), and 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane (DDT)) in food commonly consumed in Lagos and Ibadan, Southwest, Nigeria. Health risk associated with human exposure via food intake was evaluated with a statistical predictive model. About 248 composite food samples from 8 categories were analyzed in Lagos and Ibadan. Sample extraction and clean-up were by QueChERS method and extracts injected into GC-μECD. ƩDDT concentration was highest in meat products, aquatic foods, dairy products, edible oils, fruits, and cereals, while ƩHCHs were highest in chicken eggs and vegetables. ƩOCP concentrations (ng/g) in food categories were 6.09±1.6-6.85±0.9 (meat), 5.29±2.0-12.3±14 (aquatic foods), 4.86±1.7-5.89±0.8 (dairy products), 4.53±0.8-6.32±1.1 (edible oils), 3.32±1.3 (eggs), 3.54±1.0-4.80±1.5 (fruits), 4.16±2.7-4.40±0.8 (vegetables), and 6.12±2.0-6.62±0.9 (cereals). The estimated average daily intake of OCPs was 5.91, 12.5, 4.41, 6.40, 1.53, 5.14, 3.95, and 16.7 ng/kg bw/day through the consumption of meat products, aquatic foods, dairy products, edible oils, chicken eggs, fruits, vegetables, and cereals, respectively. The health risk of residual OCPs via ingestion of foods considered in this study was <1, which implied no potential health risk at the current consumption rate. However, regular monitoring of OCPs residues in food is highly recommended. Finally, the method scaled the analytical Eco-Scale evaluation and Green Analytical Chemical Procedure Index as "an acceptable green analysis method."

Laboratory-Scale Preparation and Characterization of Dried Extract of Muirapuama (Ptychopetalumolacoides Benth) by Green Analytical Techniques

This work reports on the preparation of a drying process from the ethanolic extract of Muirapuama and its characterization through green analytical techniques. The spray-drying processes were performed by using ethanolic extract in a ratio of 1:1 extract/excipient and 3² factorial design. The properties of dried powder were investigated in terms of total flavonoid content, moisture content, powder yield, and particle size distribution. An analytical eco-scale was applied to assess the greenness of the developed protocol. Ultra-high performance liquid chromatography (UHPLC)with reduced solvent consumption in the analysis was compared to the conventional HPLC method. A Fourier transform near-infrared (FT-NIR) spectroscopic method was applied based on the principal component scores for the prediction of extract/excipient mixtures and partial least squares regression model for quantitative analysis. NIR spectroscopy is an economic, powerful, and fast methodology for the detection of excipient in muirapuama dried extracts, generating no residue in the analysis. Scanning electron microscopy (SEM) images showed samples with a higher concentration of excipient, presenting better morphological characteristics and a lower moisture absorption rate. An eco-scale score value of 85 was achieved for UHPLC and 100 was achieved for NIR (excellent green analysis). Above all, these methods are rapid and green for the routine analysis of herbal medicines based on dried extracts.

Digitally enhanced thin layer chromatography for simultaneous determination of norfloxacin and tinidazole with the aid of Taguchi orthogonal array and desirability function approach: Greenness assessment by analytical Eco-Scale

In this study, an eco-friendly fast simple method was developed for simultaneous determination of norfloxacin and tinidazole based on thin-layer chromatography and image-processing analysis. The binary mixture was separated using reversed phase - thin layer chromatography plates and 30% trifluoroacetic acid only as mobile phase. Mobile phase composition was optimized using Taguchi orthogonal array and Derringer's desirability function. The plates were viewed under UV lamp and photographed by iPhone camera followed by image processing with Fiji software using integrated density as the measured response. As decreasing illumination increases the sensitivity of the method, this method was applied on two different ranges for each drug. The first one was 0.6-6.0 and 0.9-9.0 µg/spot for norfloxacin and tinidazole, respectively measured on the original image with normal illumination. The second one was measured after decreasing the illumination of the captured images at 0.06-0.60 and 0.09-0.90 µg/spot for norfloxacin and tinidazole, respectively. The proposed method was successfully applied for the determination of both drugs in tablets dosage form without interference from the commonly encountered excipients. Analytical Eco-Scale was used to evaluate the greenness profile of the proposed method and it was found to be excellent green analytical method.