Greenness assessment of chromatographic methods used for analysis of empagliflozin: a comparative study

The analytical chemistry community is attempting to incorporate green chemistry concepts in the development of analytical techniques to redefine analytical methods and dramatically modify the philosophy of analytical technique development. Each greenness assessment method has its own benefits and drawbacks, as well as its own procedures. The results of each greenness assessment method produce numerous deductions regarding the selection of a greenest chromatographic method on which the determination of a greenness assessment tool depends. The current study examined the greenness behavior of 26 reported chromatographic methods in the literature for the evaluation of the medicine empagliflozin using three evaluation methods: the national environmental methods index (NEMI), the eco-scale assessment (ESA), and the green analytical procedure index (GAPI). This comparative study discussed the value of using more than one greenness evaluation methods while evaluating. The findings showed that the NEMI was a less informative and misleading tool. However, the ESA provided reliable numerical assessments out of 100. Despite the GAPI being a complex assessment compared to the others, it provided a fully descriptive three-colored pictogram and a precise assessment. The findings recommended applying more than one greenness assessment tool to evaluate the greenness of methods prior to planning laboratory-based analytical methods to ensure an environment friendly process

Application of Hantzsch reaction for sensitive determination of eflornithine in cream, plasma and urine samples

Eflornithine (EFN) is an anti-Trypanosoma brucei agent for the medication of sleeping sickness and widely distributed for the treatment of hirsutism (unwanted facial hair in women). The presented work demonstrates a comprehensive analytical approach for the spectrofluorometric determination of EFN in commercial cream samples and various biological samples. The proposed method is based on the formation of a highly yellow–green fluorescence dihydropyridine derivative after the interaction between EFN and acetylacetone/formaldehyde reagent in a slightly acidic medium. Furthermore, the optimal variables such as reagent volumes, pH of the medium, heating time, buffer volume, heating temperature and diluting solvent were carefully selected to achieve the maximum fluorescence activity. The fluorescence activity for the formed derivative was measured at λemission = 477 nm after λexcitation = 418 nm. Concerning linearity, accuracy, sensitivity, precision and robustness, the presented method was validated and verified according to ICH guidelines. Moreover, the proposed work offered a selective determination for EFN in various brands of pharmaceutical cream without any interference from excipients. Eventually, the current approach was assured to be successful in the estimation of EFN in urine and plasma samples with acceptable recovery results

Xanthene based resonance Rayleigh scattering and spectrofluorimetric probes for the determination of cyclobenzaprine: Application to content uniformity test

In this work, a resonance Rayleigh scattering technique and a spectrofluorimetric technique were applied to the quantification of cyclobenzaprine through two validated methods. The suggested methods are based on a facile association complex formation between cyclobenzaprine and eosin Y reagent in the acidic medium. The resonance Rayleigh scattering method relied on the enhancement in the resonance Rayleigh scattering spectrum of eosin Y at 370 nm after the addition of cyclobenzaprine. On the other hand, the spectrofluorimetric quantification relied on the quenching effect of cyclobenzaprine on the fluorescence strength of the eosin Y reagent at 545 nm (excitation wavelength at 300 nm). The suggested methods were linear over the ranges of 0.07–1.75 μg/mL and 0.15–2.0 μg/mL with detection limit values of 0.023 μg/mL and 0.048 μg/mL for the resonance Rayleigh scattering method and the spectrofluorimetric method, respectively. All reaction conditions for cyclobenzaprine–eosin Y formation were experimentally evaluated and optimized. In addition, both methods were validated based on ICH rules. Furthermore, the developed methods were practically applied to the analysis of cyclobenzaprine in its commercial tablet dosage form with acceptable recoveries. Moreover, the content uniformity test of the commercial cyclobenzaprine tablets was successfully applied using the proposed spectroscopic methods based on USP rules

Evaluation of Greenness of LC-MS Chromatographic Methods for Simultaneous Analysis of Mixtures of Serotonin, Dopamine, Acetylcholine, GABA and Glutamate: AGREE Tool Application

The analytical GREEnness metric (AGREE) tool is widely used as a reliable greenness assessment method for chromatographic analyses. The AGREE tool has the ability to determine the greenness of analytical methods in terms of both quality and quantity, whereas other commonly used methods assess the greenness either quantitatively or qualitatively. Greenness profiles of six chromatographic methods for simultaneous estimations of serotonin, dopamine, acetylcholine, GABA and glutamate were assessed using AGREE and NEMI tools as a case study. The AGREE assessment tool proved to be user-friendly, and provides a full profile of assessment, hence it can be described as the tool of choice for the assessment of LC-MS chromatographic methods. For optimum application, the weights of 4 of the 12 assessment criteria were set high (weight of four) due to their importance, namely criteria number 7 (waste), number 8 (analysis thruput/number of analytes per run), number 11 (toxicity) and number 12 (operator’s safety). Setting proper weights of the assessment criteria contributed significantly to the discrimination of greenness of the compared methods. The selected greenest method for the analysis of the proposed quinary mixture showed an AGREE tool pictogram with a 0.66 score. Additionally, the selected method allows simultaneous estimation of seven constituents in total. It offers high sensitivity, allowing detection of acetylcholine, serotonin and glutamate at levels as low as 2 pg, and dopamine, norepinephrine, GABA and glycine at levels as low as 10 pg, and finally offers fast analysis where all components can be analyzed within 5 min

Selenium nanoparticles synthesized using an eco-friendly method: Dye decolorization from aqueous solutions, cell viability, antioxidant, and antibacterial effectiveness

International audienceSelenium nanoparticles (SeNPs) were fabricated using a green microwave technique in the presence of ascorbic acid. The morphological features indicated that the semi-spherical SeNPs with a diameter 8.5-22nm were configured in agglomerated spherical shapes with diameters around 0.47-0.71 μm. Furthermore, the removal of Fuchsin Basic dye from aqueous solutions was investigated upon variation of concentration of SeNPs. The degradation efficiency achieved 100 % for 10 mg of SeNPs after 34 min of visible light irradiation time. The antioxidant activity 2 was tested via DPPH radical scavenging assay and displayed that the highest scavenging capacity (311.115.72 mg/g) was achieved by SeNPs at a concentration of 106.25 mg/mL. Otherwise, the cell viability of SeNPs through human fibroblasts cell lines in-vitro was reduced to be 75.13.8 % with nanoparticle concentration around 500 μg/mL. The antibacterial activity was investigated against gram-negative and gram-positive bacteria such as Escherichia coli (E.coli), Pseudomonas aeruginosa (P. aeruginosa), Klebsiella pneumoniae (K. pneumonia), Staphylococcus aureus (S. aureus), and Bacillus subtilis (B. subtilis) bacteria after one day of exposure. It was illustrated that SeNPs did not display an activity towards Staphylococcus aureus, while it possessed the highest one against Escherichia coli with MBC of 50 ± 1.76 g/mL compared with 26 ± 0.6 g/mL for the standard antibiotic. These tremendous properties of SeNPs indicate that manipulating multifunctional nanoparticles for versatile wound and skin treatment applications is highly encouraging

Evaluation of Greenness of LC-MS Chromatographic Methods for Simultaneous Analysis of Mixtures of Serotonin, Dopamine, Acetylcholine, GABA and Glutamate: AGREE Tool Application

The analytical GREEnness metric (AGREE) tool is widely used as a reliable greenness assessment method for chromatographic analyses. The AGREE tool has the ability to determine the greenness of analytical methods in terms of both quality and quantity, whereas other commonly used methods assess the greenness either quantitatively or qualitatively. Greenness profiles of six chromatographic methods for simultaneous estimations of serotonin, dopamine, acetylcholine, GABA and glutamate were assessed using AGREE and NEMI tools as a case study. The AGREE assessment tool proved to be user-friendly, and provides a full profile of assessment, hence it can be described as the tool of choice for the assessment of LC-MS chromatographic methods. For optimum application, the weights of 4 of the 12 assessment criteria were set high (weight of four) due to their importance, namely criteria number 7 (waste), number 8 (analysis thruput/number of analytes per run), number 11 (toxicity) and number 12 (operator’s safety). Setting proper weights of the assessment criteria contributed significantly to the discrimination of greenness of the compared methods. The selected greenest method for the analysis of the proposed quinary mixture showed an AGREE tool pictogram with a 0.66 score. Additionally, the selected method allows simultaneous estimation of seven constituents in total. It offers high sensitivity, allowing detection of acetylcholine, serotonin and glutamate at levels as low as 2 pg, and dopamine, norepinephrine, GABA and glycine at levels as low as 10 pg, and finally offers fast analysis where all components can be analyzed within 5 min

Sustainable PVP-Capped Silver Nanoparticles as a Free-Standing Nanozyme Sensor for Visual and Spectrophotometric Detection of Hg²⁺ in Water Samples: A Green Analytical Method

In the proposed method, microwave-assist heating and AgNO3/trisodium citrate were used to create the polyvinylpyrrolidone-capped silver nanoparticles (PVP-AgNPs) sensor. This sensor had a peroxidase-like activity that could catalytically oxidize O-phenylenediamine (OPD, colourless) into 2,3-diaminophenazine (ox-OPD, greenish-yellow colour) in the presence of H2O2, otherwise, in the presence of Hg2+, this pass has been effectively inhibited. The degree of colour fading was directly correlated with Hg2+ concentration. These results indicated the selectivity of Hg2+ ions toward PVP-AgNPs after establishing the PVP-AgNPs/OPD/H2O2 system. This selectivity was proved by the negative results obtained from other mon-, di-, and trivalent ions such as Na+, K+, Ca2+, Mg2+, Ba2+, Co2+, Ni2+, Cd2+, and Cr3+, instead of Hg2+. Consequently, a reliable, selective, and eco-effective spectrophotometric approach was designed for the detection of Hg2+ in various types of water samples. LOD was extended to lower than 0.1 µM, and a fading in the obtained colour was shown by the naked eye at a concentration higher than 1.5 µM of Hg2+. The elemental details for preparing the used PVP-AgNPs, such as particle size, morphology, polydispersity index (PdI), and their UV-visible spectrum, were identified by SEM technique, TEM, UV-visible spectrophotometer, and zeta-sizer device. Thus, the peroxidase mimicking the activity of OPD/H2O2 was confirmed by a fluorescence technique. The greenness profile of this work was confirmed after applying a reported assessment tool

Sustainable PVP-Capped Silver Nanoparticles as a Free-Standing Nanozyme Sensor for Visual and Spectrophotometric Detection of Hg2+ in Water Samples: A Green Analytical Method

In the proposed method, microwave-assist heating and AgNO3/trisodium citrate were used to create the polyvinylpyrrolidone-capped silver nanoparticles (PVP-AgNPs) sensor. This sensor had a peroxidase-like activity that could catalytically oxidize O-phenylenediamine (OPD, colourless) into 2,3-diaminophenazine (ox-OPD, greenish-yellow colour) in the presence of H2O2, otherwise, in the presence of Hg2+, this pass has been effectively inhibited. The degree of colour fading was directly correlated with Hg2+ concentration. These results indicated the selectivity of Hg2+ ions toward PVP-AgNPs after establishing the PVP-AgNPs/OPD/H2O2 system. This selectivity was proved by the negative results obtained from other mon-, di-, and trivalent ions such as Na+, K+, Ca2+, Mg2+, Ba2+, Co2+, Ni2+, Cd2+, and Cr3+, instead of Hg2+. Consequently, a reliable, selective, and eco-effective spectrophotometric approach was designed for the detection of Hg2+ in various types of water samples. LOD was extended to lower than 0.1 µM, and a fading in the obtained colour was shown by the naked eye at a concentration higher than 1.5 µM of Hg2+. The elemental details for preparing the used PVP-AgNPs, such as particle size, morphology, polydispersity index (PdI), and their UV-visible spectrum, were identified by SEM technique, TEM, UV-visible spectrophotometer, and zeta-sizer device. Thus, the peroxidase mimicking the activity of OPD/H2O2 was confirmed by a fluorescence technique. The greenness profile of this work was confirmed after applying a reported assessment tool

Electrospun nanofibrous scaffolds of ε-polycaprolactone containing graphene oxide and encapsulated with magnetite nanoparticles for wound healing utilizations

Wound healing treatment with a nanofibrous matrix is a serious demand to avoid associated complications, including bacterial infections. Magnetite nanoparticles (MNPs) were encapsulated into electrospun nanofibrous scaffolds of ε -polycaprolactone (PCL) containing graphene oxide (GO) nanosheets. The structural and morphological behaviors of the obtained scaffolds were investigated. The modification of nanofibers via the addition of MNPs generated a slight change of morphology, whereas the fibers’ diameters were around 0.2–0.5, 0.1–0.3, 0.1–0.2, and 0.1–0.3 μ m for 0.0NPs-GO@PCL, 0.1NPs-GO@PCL, 0.2NPs-GO@PCL, and 0.3NPs-GO@PCL, respectively. Moreover, the roughness average (Ra) increased from 119 nm to be about 169 nm from the lowest and the highest contributions of MNPs. The Human fibroblasts cell line (HFB4) reached around 98.4 ± 3.1% cell viability for 0.2MNPs-GO@PCL composition. The antibacterial activity of the highest contribution of MNPs reached about 11.4 ± 1.6 mm and 12.3 ± 1.2 mm against S. aureus and E. coli , respectively. The in-vitro cells’ attachment of HFB4 showed that cells were adhered to and proliferated through the nanofibrous scaffolds. Cells also spread and grew significantly as the modification via MNPs. Thus, indicating that designing of new scaffold for wound healing and disinfection utilization could be reached via tailoring of electrospun products encapsulating with biocompatible substances such as graphene oxide and magnetite

Synthesis and Self-assembly of Novel Nanofeather-like Fluorescent Alkyloxy-Containing Diphenyl Ether Organogelators

In this study, novel fluorescent low molecular-weight organogelators are derived from diphenyl ethers and substituted with para-alkoxy groups of different aliphatic chain lengths. The present research promotes the preparation of innovative nanofeather-like assemblies from the synthesized diphenyl ether-derived organogelators. The gelation performance of the prepared alkoxy-substituted diphenyl ethers was reported. The synthesis procedure was achieved by using a base-catalyzed reaction of hydroxyl-substituted diphenyl with various alcohols of different aliphatic chain lengths. The chemical structures of the synthesized diphenyl ether derivatives were studied by 1H/13C NMR and infrared spectroscopy. Fluorescence and UV–vis absorption spectral analyses showed solvatochromism. The diphenyl ether derivatives with longer alkoxy terminal substituents showed enhanced thermoreversible gelation activity as compared to the diphenyl ether derivatives with shorter alkoxy terminal substituents. The morphological properties of the self-assembled diphenyl ethers were studied by transmission electron microscopy and scanning electron microscopy, which showed supramolecular architectures of highly ordered nanofeathers, enforced by van der Waals interactions and π-stacks. Depending on the length of the aliphatic tail, different morphologies were detected, including nanofeathers, nanofibers, and nanosheets. The antimicrobial and cytotoxic properties of the prepared diphenyl ether-derived organogelators were examined to confirm their possible use in various fields like drug delivery systems