BMC Chemistry

Separation properties and fouling resistance of polyethersulfone membrane modified by fungal chitosan
Iman HN, Susilo H, Satriyatama A, Budi IDM, Kurnia KA, Wenten IG and Khoiruddin K
This research explores the enhancement of polyethersulfone (PES) membranes through the incorporation of chitosan derived from the lignicolous fungus Ganoderma sp. Utilizing wet phase inversion and solution casting techniques, chitosan was successfully integrated into the PES matrix, as confirmed by Fourier Transform Infrared Spectroscopy (FT-IR), which indicated a high deacetylation degree of 75.7%. The incorporation of chitosan significantly increased the membrane hydrophilicity, as evidenced by a reduction in the water contact angle and a substantial improvement in pure water permeability, from 17.9 L m h bar to 27.3 L m h bar. The membrane anti-fouling properties were also notably enhanced, with the Flux Recovery Ratio (FRR) increasing from approximately 60-80%. Moreover, the chitosan-modified PES/CS membrane, particularly at a 5% chitosan concentration, demonstrated exceptional efficacy in pollutant removal, achieving over 90% elimination of total suspended solids, cadmium (Cd), and lead (Pb), alongside a 79% reduction in color during the treatment of textile wastewater.
Novel pyrrole based triazole moiety as therapeutic hybrid: synthesis, characterization and anti-Alzheimer potential with molecular mechanism of protein ligand profile
Khan S, Iqbal T, Khan MB, Hussain R, Khan Y and Darwish HW
As a springboard to explore novel potent inhibitors of cholinesterase enzymes (AChE and BChE) responsible for causing Alzheimer disorder, the current study was conducted to synthesize pyrrole derived triazole based Schiff base scaffolds by facile synthetic route. These compounds were validated by HNMR, CNMR and HREI-MS. All these scaffolds (1-16) were examined for their inhibitory activity against AChE and BChE in contrast to Donepezil (10.20 ± 0.10 and 10.80 ± 0.20 µM) and Allanzanthone (12.40 ± 0.10 and 13.10 ± 0.10 µM). All pyrrole derived triazole based Schiff base scaffolds (1-16) showed varied range of inhibitory potentials against acetylcholinesterase and butyrylcholinesterase enzymes with lowest inhibition concentration values ranging from 5.10 ± 0.40-27.10 ± 0.10 µM (for AChE) and 5.60 ± 0.30-28.40 ± 0.30 µM (for BChE). SAR analysis of these derivatives revealed analog 7 as lead molecule against targeted enzyme, while analog 6 and 11 were ranked as second and third most potent scaffolds. Binding affinity and selectivity of potent molecules against targeted enzymes were examined by molecular docking and obtained results showed that potent molecule have versatile significant binding interactions with stated enzymes. Furthermore, safety profiles of potent analogues were predicted via ADMET protocols.
New N-amino-5-cyano-6-pyridones as antimicrobial small molecules endowed with DNA gyrase a inhibitory activity: design, one-pot synthesis, biological assessment and in silico insights
Kamaly OA, Younes AS, Harras MF, Sabour R, Alsfouk AA and Ibrahim MH
A set of innovative N-amino-5-cyano-6-pyridones derivatives was developed and produced using one-pot three-component procedures. The evaluated molecules were examined for their antimicrobial efficacy. Based on the acquired findings, most of the investigated compounds had promising antimicrobial properties. Out of these derivatives of 3-cyanopyridine, compounds 3d and 3e exhibited minimum inhibitory concentrations (MIC) of 3.91 µg/mL against E.coli. In vitro evaluation of DNA gyrase A displayed that molecule 3d exhibited promising potency as an inhibitor, with an IC value of 1.68 µg/mL compared to ciprofloxacin (IC = 0.45 µg/mL). Furthermore, it was observed that molecule 3e exhibited a moderate inhibitory effect, as indicated by its IC value of 3.77 µg/mL. A kinetics study conducted to assess the time required to kill E. coli bacteria demonstrated that gentamycin and compounds 3d and 3e exhibited bactericidal effects within a time frame of 90-120 min. Based on the ADME predictions, compounds 3d and 3e are expected to have favorable oral bioavailability and are unlikely to penetrate the blood-brain barrier. Computational mutagenicity and tumorigenicity studies were conducted on compounds 3d and 3e. The molecular docking investigation has conclusively demonstrated the binding of compounds 3d and 3e to the target DNA gyrase A enzyme, further reinforcing the existing data.
Removal of As(V) and Cr(VI) using quinoxaline chitosan schiff base: synthesis, characterization and adsorption mechanism
Abdelwahab HE, Elhag M and El Sadek MM
Elevated Arsenic and Chromium levels in surface and ground waters are a significant health concern in several parts of the world. Chitosan quinoxaline Schiff base (CsQ) and cross-linked chitosan quinoxaline Schiff base (CsQG) were prepared to adsorb both Arsenate [As(V)] and Chromium [Cr(VI)] ions. The thermo-gravimetric analysis (TGA), X-ray diffraction analysis (XRD), and Fourier-transform infrared spectroscopy (FTIR) were used to investigate the prepared Schiff bases (CsQ) and (CsQG). The UV-VIS spectra showed a shift in the wavelength area of the modified polymer, indicating the reaction occurrence, besides the variation of the shape and intensity of the peaks. The XRD patterns showed the incensement of the amorphous characteristic. On the other hand, the thermal stability of the modified polymers is better according to TGA studies; also, the morphology of the modified chitosan was investigated before and after crosslinking (CsQ and CsQG) using a scanning electron microscope (SEM) where the surface was fall of wrinkles and pores, which then were decreased after cross-linking. Contact time, temperature, pH, and initial metal ion concentration were all studied as factors influencing metal ion uptake behavior. The Langmuir, Temkin, Dubinin-Radushkevich, and Freundlich isotherm models were used to describe the equilibrium data using metal concentrations of 10-1000 mg/L at pH = 7 and 1 g of adsorbent. The pseudo-first-order and pseudo-second-order kinetic parameters were evaluated. The experimental data revealed that the adsorption kinetics follow the mechanism of the pseudo-second-order equation with R values (0.9969, 0.9061) in case of using CsQ and R values (0.9989, 0.9999) in case of using CsQG, demonstrating chemical sorption is the rate-limiting step of the adsorption mechanism. Comparing the adsorption efficiency of the synthesized Schiff base and the cross-linked one, it was found that CsQ is a better adsorbent than CsQG in both cases of As(V) and Cr(VI) removal. This means that cross-linking doesn't enhance the efficiency as expected, but on the contrary, in some cases, it decreases the removal. In addition, the newly modified chitosan polymers work better in As(V) removal than Cr(VI); the removal is 22.33% for Cr(VI) and 98.36% for As(V) using CsQ polymer, whereas using CsQG, the values are 6.20% and 91.75% respectively. On the other hand, the maximum adsorption capacity (Qm) for As(V) and Cr(VI) are 8.811 and 3.003 mg/g, respectively, using CsQ, while in the case of using CsQG, the Qm value reaches 31.95 mg/g for As(V), and 103.09 mg/g for Cr(VI).
Development and validation of HPLC-UV and LC-MS/MS methods for the quantitative determination of a novel aminothiazole in preclinical samples
Basavanakatti VN, Ali M, Bharathi DR, Murtuja S, Sinha BN, Jayaprakash V and Shakeel F
Aminothiazoles are the important class of chemical groups which have proven their broad range of biological activities. A novel aminothiazole (21MAT) was quantified in analytical solutions using a high-performance liquid chromatography (HPLC) approach that was developed and partially validated for the analysis of in vitro experimental samples. An isocratic elution on reverse phase Phenomenex Luna C (50 mm × 4.6 mm, 5 μm) column with 55% 0.1% v/v orthophosphoric acid in water and 45% of orthophosphoric acid in acetonitrile at a flow rate of 1 mL/min was used. The analyte was detected at 272 nm. Similar to this, a robust bioanalytical technique, LC-mass spectrometry (LC-MS/MS) was created and verified to measure 21MAT in rat plasma for use in in vitro screening study samples and early-stage pharmacokinetic research. The protein precipitation method was used to extract 21MAT from plasma. The mixture of 95: 5% v/v methanol: acetonitrile and 0.1% v/v formic acid, along with 15% of 5 mM ammonium formate solution, was used to separate the mixture on a reverse phase Waters Xterra RP C (150 mm × 4.6 mm, 5 μm) column at a flow rate of 1 mL/min. Using electro spray ionisation mode in multiple reaction monitoring mode, the analyte and internal standard (a structural analogue) were both identified. According to current criteria, all validation parameters (specificity, selectivity, accuracy, precision, recovery, matrix factor, hemolysis effect, and stability) were evaluated in rat plasma. The area response of 21MAT was found to be linear over the concentration range of 1.25-1250 ng/mL in rat plasma. Both techniques are suitable for use in any format of preclinical research and were sufficiently reliable to measure 21MAT precisely in various matrices. In silico prediction helped in understanding absorption, distribution, metabolism, excretion, and toxicity (ADMET) behaviour of the molecule. Both developed LC-MS/MS and HPLC-UV methods were successfully used to quantify the analyte in in vitro screening study samples.
Pharmacophore-based virtual screening, molecular docking, and molecular dynamics investigation for the identification of novel, marine aromatase inhibitors
Kotb MA, Abdelmawgood IA and Ibrahim IM
Breast cancer remains a leading cause of mortality among women worldwide. Our current research focuses on identifying effective therapeutic agents by targeting the human aromatase enzyme. Aromatase inhibitors (AIs) have been effective in treating postmenopausal breast cancer but face challenges such as drug resistance and long-term side effects like cognitive decline and osteoporosis. Natural products, especially from marine organisms, are emerging as potential sources for new drug candidates due to their structural diversity and pharmacological properties. This study aims to discover marine natural products capable of inhibiting human aromatase by combining ligand-based and structure-based pharmacophore models for virtual screening against the Comprehensive Marine Natural Products Database. From the initial virtual screening of more than 31,000 compounds, 1,385 marine natural products were identified as possible candidates. Following initial molecular docking analysis, only four compounds managed to pass the criteria this research has introduced to confirm strong binding affinity to aromatase. All four compounds yielded acceptable binding affinities, with CMPND 27987 having the highest -10.1 kcal/mol. All four hits were subjected to molecular dynamics, and CMPND 27987 was further confirmed to be the most stable at the protein's active site, with an MM-GBSA free binding energy of -27.75 kcal/mol. Our in silico studies indicate that CMPND 27987 interacts effectively within the binding site of the human aromatase, maintaining high affinity and stability. Based on these findings, we propose that CMPND 27987 could hold significant potential for further lead optimization and drug development.
Chromatographic assay of recently approved co-formulation of Vonoprazan fumarate with low dose Aspirin: AGREE, Complex MoGAPI, and RGB 12-model assessments
Moneim MMA and Hamdy MMA
Two simple, valid and green chromatographic based techniques are developed in the present work for first time to simultaneously analyze the recently approved combination of Aspirin (ASP) with the novel gastro-protective agent Vonoprazan (VON). First method is an HPLC-DAD "diode array detection", where separation was successful using C18 (250 × 4.6 mm) column with isocratic elution of phosphate buffer-pH 6.8 and acetonitrile in ratio of 63:37 with detection at 230 nm. Second method is an HPTLC method on HPTLC silica plates using ethyl acetate: ethanol (75%): ammonia (5:5:0.05 v/v) mobile phase followed by densitometric scanning at 230 nm. The methods were applied successfully for analysis of VON and ASP mixture in laboratory-prepared tablets and the methods were validated in regards to linearity, precision, accuracy and selectivity. The proposed methods are assessed for their greenness and whiteness as well using the "Analytical GREEnness Metric Approach", "Complementary Modified Green Analytical Procedure Index" and the new algorithm "RGB 12 model" (Red-Green-Blue) and proved the greenness and the sustainability of the methods in the routine assay of the newly marketed formulation.
La-supported SnO-CaO composite catalysts for efficient malachite green degradation under UV-vis light
Parsafard N and Aghajari G
This study presents the development and optimization of La@SnO-CaO composite catalysts for efficient photocatalytic degradation of malachite green dye in aqueous solutions under UV-vis light irradiation. The catalysts were prepared via conventional incipient-wetness impregnation and thoroughly characterized using advanced analytical techniques, including X-ray diffraction, Fourier transform infrared spectroscopy, UV-vis diffuse reflectance spectroscopy, N adsorption-desorption analysis, and scanning electron microscopy. To optimize photodegradation efficiency, the effects of three independent factors were systematically investigated using response surface methodology: Temperature, pH, and Sn/Ca molar ratio. Our results reveal optimal conditions for maximum dye degradation: pH 7, Sn/Ca molar ratio of 0.33, and a process time of 35 min, resulting in a maximum photodegradation efficiency of 98.80% for malachite green dye. Notably, visible light exhibited a more pronounced effect on dye degradation compared to UV light over time, with visible light achieving 25% greater dye removal after 60 min of illumination. Furthermore, the catalyst showed excellent recyclability, retaining 85% of its initial activity after five consecutive cycles. These findings contribute significantly to the development of sustainable methods for dye removal from wastewater and highlight the potential of La@SnO-CaO composite catalysts in environmental remediation processes, particularly in treating textile industry effluents.
New chemometrics-assisted spectrophotometric methods for simultaneous determination of co-formulated drugs montelukast, rupatadine, and desloratadine in their different dosage combinations
Sharkawi MMZ, Farid NF, Hassan MH and Hassan SA
Two accurate, precise and robust multivariate chemometric methods were developed for the simultaneous determination of montelukast sodium (MON), rupatadine fumarate (RUP) and desloratadine (DES). These methods provide a cost-effective alternative to chromatographic techniques by utilizing spectrophotometry in pharmaceutical quality control. The proposed approaches, partial least squares-1 (PLS-1) and artificial neural network (ANN), were optimized using genetic algorithm (GA) to select the most influential wavelengths, enhancing model performance. A five-level, three-factor design was employed to construct a calibration set with 25 mixtures, utilizing concentration ranges of 3-19, 5-25, and 4-20 µg.mL for MON, RUP, and DES, respectively. An independent validation set was employed to assess the performance of the models. GA significantly improved the PLS-1 and ANN models for RUP and DES, though minimal enhancement was observed for MON. These methods were successfully applied to the simultaneous quantification of the compounds in pharmaceutical formulations and proved useful as stability-indicating assays for RUP, given that DES is a known degradation product. The developed methods offer a valuable tool for impurity profiling and quality control in pharmaceutical analysis.
AQbD-enhanced green RP-UPLC-PDA methodology for quantification and forced degradation studies for omeprazole, amoxicillin, and rifabutin
Baffinsha SPA, Ragupathi V and Chanduluru HK
The ternary combination like omeprazole (OMP), amoxicillin (AMX), and rifabutin (RFB) was approved by the FDA in November 2019 for combating Helicobacter pylori infections and ulcers caused by this infection. This study aims to develop and authenticate a robust and eco-friendly RP-UPLC technique aimed at the concurrent analysis of OMP, AMX, and RFB, following ICH guidelines, Analytical Quality by Design (AQbD), and green analytical chemistry (GAC) principles. The analysis used the Thermo C18 column (100 mm × 2.1 mm, 1.7 µm), ethanol, and formic acid solution (43:57) as mobile phase with a flow rate of 0.2 ml/min at 272 nm. The method was developed based on the ICH Q14 and validated according to ICH Q2(R1) followed by Forced degradation studies under various conditions. The method showed good linearity for OMP, AMX, and RFB, with coefficient of determination (r2) of 0.9995, 0.9993, and 0.9997, respectively. Precision studies indicated low %RSD values, confirming high reproducibility. Forced degradation studies confirmed the stability of the drugs for 30 min in acid, base, and redox reactions, and they were also stable for 6 h at 105 °C in dry conditions. GAPI assessment depicted a green and yellow pictogram, AGREE scored 0.85, BAGI scored 80, and RGB12 Whiteness Assessment Tool scored 97.5%. The developed RP-UPLC-PDA technique is robust and reliable for the concurrent quantification of the triple combination. It aligns with sustainability goals, enhancing the efficiency and environmental sustainability of pharmaceutical analysis, and setting a benchmark for future analytical methods.
Simultaneously quantifying a novel five-component anti- migraine formulation containing ergotamine, propyphenazone, caffeine, camylofin, and mecloxamine using UV spectrophotometry and chemometric models
Abbas AEF, Abdelshafi NA, Gamal M, Halim MK, Said BAM, Naguib IA, Mansour MMA, Morshedy S and Salem YA
This study presents a new method for simultaneously quantifying a complex anti-migraine formulation containing five components (ergotamine, propyphenazone, caffeine, camylofin, and mecloxamine) using UV spectrophotometry and chemometric models. The formulation presents analytical challenges due to the wide variation in component concentrations (ERG: PRO: CAF: CAM: MEC ratio of 0.075:20:8:5:4) and highly overlapping UV spectra. To create a comprehensive validation dataset, the Kennard-Stone Clustering Algorithm was used to address the limitations of arbitrary data partitioning in chemometric methods. Three different chemometric models were evaluated: Classical Least Squares (CLS), Partial Least Squares (PLS), and Multivariate Curve Resolution-Alternating Least Squares (MCR-ALS). Among these, MCR-ALS demonstrated excellent performance, achieving recovery values of 98-102% for all components, accompanied by minimal root mean square errors of calibration (0.072-0.378) and prediction (0.077-0.404). Moreover, the model exhibited high accuracy, with relative errors ranging from 1.936 to 3.121%, bias-corrected mean square errors between 0.074 and 0.389, and a good sensitivity (0.2097-1.2898 μg mL) for all components. The Elliptical Joint Confidence Region analysis further confirmed the predictive performance of the models, with MCR-ALS consistently showing the smallest ellipses closest to the ideal point (slope = 1, intercept = 0) for most analytes, indicating superior accuracy and precision. The approach's sustainability was rigorously assessed using six advanced metrics, validating its environmental friendliness, economic viability, and practical application. This approach effectively resolves complex pharmaceutical formulations, contributing to sustainable development objectives in quality control processes.
Olive mill wastewater treatment using vertical flow constructed wetlands (VFCWs)
Abu-Dalo M, Abu-Dalo D, Halalsheh M and Al Bawab A
The study explores a synergistic two-phase system to treat olive mill wastewater (OMW), comprising a multilayer adsorbent filter (pretreatment) and a vertical flow constructed wetland (VFCW). The pretreatment phase includes layers of commercial granular activated carbon (CGAC) and volcanic tuff (VT), while the VFCW phase consists of planted tank with Phragmites australis reeds and unplanted tanks. Initially, municipal wastewater is introduced into the VFCW to establish the required microbial community. Then, pre-treated OMW is passed through the VFCW. The removal rates of various pollutants were assessed. The planted VFCW showed superior removal efficiencies, averaging 97.82% for total chemical oxygen demand (COD), 92.78% for dissolved oxygen demand (COD), 99.61% for total phenolic compounds (TPC), 98.94% for total nitrogen (TN), 96.96% for ammonium, and 95.83% for nitrate. In contrast, the unplanted VFCW displayed lower removal efficiencies, averaging 91.47% for COD, 77.82% for COD, 98.53% for TPC, 97.51% for TN, 92.04% for ammonium, and 90.82% for nitrate. These findings highlight the significant potential of VFCWs, which offer an integrated approach to OMW treatment by incorporating physical, chemical, and biological mechanisms within a single treatment system.
Molecular exploration of natural and synthetic compounds databases for promising hypoxia inducible factor (HIF) Prolyl-4- hydroxylase domain (PHD) inhibitors using molecular simulation and free energy calculations
Sayaf AM, Kousar K, Suleman M, Albekairi NA, Alshammari A, Mohammad A, Khan A, Agouni A and Yeoh KK
Hypoxia-inducible factors (HIFs) are transcription factors that regulate erythropoietin (EPO) synthesis and red blood cell (RBC) production. Prolyl-4-hydroxylase domain (PHD) enzymes are key regulators of HIF's stability and activity. Inhibiting PHD enzymes can enhance HIF-mediated responses and have therapeutic potential for diseases such as anemia, cancer, stroke, ischemia, neurodegeneration, and inflammation. In this study, we searched for novel PHD inhibitors from four databases of natural products and synthetic compounds: AfroDb Natural Products, AnalytiCon Discovery Natural Product (NP), HIM-Herbal Ingredients In-Vivo Metabolism, and Herbal Ingredients' Targets, with a total number of 13,597 compounds. We screened the candidate compounds by molecular docking and validated them by molecular dynamics simulations and free energy calculations. We identified four target hits (ZINC36378940, ZINC2005305, ZINC31164438, and ZINC67910437) that showed stronger binding affinity to PHD2 compared to the positive control, Vadadustat (AKB-6548), with docking scores of - 13.34 kcal/mol, - 12.76 kcal/mol, - 11.96 kcal/mol, - 11.41 kcal/mol, and - 9.04 kcal/mol, respectively. The target ligands chelated the active site iron and interacted with key residues (Arg 383, Tyr329, Tyr303) of PHD2, in a similar manner as Vadadustat. Moreover, the dynamic stability-based assessment revealed that they also exhibited stable dynamics and compact trajectories. Then the total binding free energy was calculated for each complex which revealed that the control has a TBE of - 31.26 ± 0.30 kcal/mol, ZINC36378940 reported a TBE of - 38.65 ± 0.51 kcal/mol, for the ZINC31164438 the TBE was - 26.16 ± 0.30 kcal/mol while the ZINC2005305 complex reported electrostatic energy of - 32.75 ± 0.58 kcal/mol. This shows that ZINC36378940 is the best hit than the other and therefore further investigation should be performed for the clinical usage. Our results suggest that these target hits are promising candidates that reserve further in vitro and in vivo validations as potential PHD inhibitors for the treatment of renal anemia, cancer, stroke, ischemia, neurodegeneration, and inflammation.
Isolation of highly polar galloyl glucoside tautomers from Saxifraga tangutica through preparative chromatography and assessment of their in vitro antioxidant activity
Tong Y, Chu M, Zhou J, Wang Q, Li G, Abd El-Aty AM and Dang J
In this work, the rapid and efficient preparation of isolated galloyl glucoside tautomer free radical inhibitors was investigated using Saxifraga tangutica as a raw material. Four highly polar galloyl glucoside tautomers, 3-O-galloyl-α-D-glucose ⇌ 3-O-galloyl-β-D-glucose (Fr2-1-1), 2-O-galloyl-α-D-glucose ⇌ 2-O-galloyl-β-D-glucose (Fr2-1-2/2-1-3), 1-O-galloyl-β-D-glucose (Fr2-2-1), and 6-O-galloyl-α-D-glucose ⇌ 6-O-galloyl-β-D-glucose (Fr2-3-1/Fr2-3-2), were obtained via two-step medium-pressure liquid chromatography (with solid loading instead of conventional liquid injection) and one-step high-performance chromatography coupled with on-line RPLC-DPPH techniques for targeted isolation. This separation integration technique not only increases sample intake and reduces time cost but also visualizes each step of targeted separation. All four compounds were isolated from the plant for the first time. In vitro antioxidant activity assays by DPPH (1,1‑diphenyl-2-picrylhydrazyl) revealed that Fr2-1-2/Fr2-1-3 (IC: 5.52 ± 0.32 μM), Fr2-2-1 (IC: 7.22 ± 0.57 μM), and Fr2-3-1/Fr2-3-2 (IC: 7.36 ± 0.25 μM) had superior free radical scavenging abilities and that both were superior to that of quercetin (IC: 18.61 ± 3.55 μM). Oxidative stress assays revealed that Fr2-1-2/Fr2-1-3 significantly inhibited oxidative stress damage in HO-induced HepG2 cells, decreased the level of ROS (P < 0.01) and protected hepatocytes. Combined with the current results, gallic acid showed greater antioxidant activity when H atoms were replaced at D-glucose -OH (C-2) than at the other three sites [-OH (C-1), -OH (C-6) and -OH (C-3)].
New thiophene derivatives: chemoselective synthesis, antitumor effectiveness, structural characterization, DFT calculations, Hirshfeld surface, and Fukui function analysis
Bin Muhsinah A, Alharbi MM, Kheder NA, Soliman SM, Ghabbour HA, Mahmoud NS, Elhaty IA and Mabkhot YN
In this study, the chemoselective synthesis of two new thiophene derivatives is presented. The structure of newly synthesized thiophenes derivatives; ethyl 4-acetyl-3-phenyl-5-(phenylamino)thiophene-2-carboxylate (5) and ethyl (E)-4-(3-(dimethylamino)acryloyl)-3-phenyl-5-(phenylamino)thiophene-2-carboxylate (8) were established using different FTIR and NMR spectral analyses. Compound 8 was isolated as single crystal and its 3D structure was determined using X-ray crystallographic analysis. Possible intermolecular interactions that control the molecular packing of 8 were elucidated using Hirshfeld topology analysis. The O…H (13.7%), H…H (55.3%) and C…C (2.3%) intermolecular interactions are the most significant. Fukui functions showed that C4 in thiophene 5 and C3 in thiophene 8 are the most reactive atoms for nucleophilic attack, while N9 in thiophene 5 and C1 in thiophene 8 are the most reactive atoms for electrophilic attack. Antitumor activity of thiophene 5 was assessed and the results showed higher activity against HepG-2 (7.46 µg/mL) compared to the HCT 116 (12.60 µg/mL) cell line.
Influence of physico-chemical properties of hydroxypropyl methylcellulose on quetiapine fumarate release from sustained release matrix tablets
Ellakwa TE, Abu-Khadra AS and Ellakwa DE
Quetiapine fumarateis a typical antipsychotic with a short half-life of 6 h and is administered multiple times daily. In this study, a copolymer for controlled delivery of quetiapine fumarate will be developed. In order to prevent side effects and improve patient compliance, hydroxypropyl methylcellulose K15M (HPMC K15M) was included in the formulation of the quetiapine fumarate oral sustained-release tablets at a concentration of 10-30%. A series of analytical methods were used to determine the characteristics of the prepared hydrogels, including Fourier transform-infrared spectroscopy, Differential scanning calorimetry, X-ray diffraction, and Scanning electron microscope. At two different pH values (1.2 and 6.8), swelling and release studies were conducted. A variety of release kinetic models was used to study drug release mechanisms. A non-Fickian diffusion mechanism released hydrogels prepared from quetiapine fumarate. It was found that swelling was increased by increasing the amount of HPMC K15M. Compared to the other batches (10-20%), the produced tablets with 30% HPMC K15M content had a better release profile after 20 h of dissolution. Because of the effective matrix complex's limited solubility in water, the drug diffuses through the gel layer at a steady rate rather than dissolving quickly.
Utilizing MEDT analysis of [3 + 2] cycloaddition reaction: x-ray crystallography of spirooxindole linked with thiophene/furan heterocycles and triazole framework
Alayyaf AA, Ali M, Alwehaibi MA, Al-Muhanna MK, Soliman SM, Ríos-Gutiérrez M, Haukka M and Barakat A
Hybridization of spirooxindole with different pharmacophores such as triazole and heterocycle such as thiophene and furan moiety was achieved by the [3 + 2] cycloaddition (32CA) reaction approach. Structural investigations of the compounds 4a and 4b were performed using X-ray single crystal structure determinations and Hirshfeld analysis. Both compounds crystallized in monoclinic crystal system. The space group is P2/c for 4a and P2/n for 4b. The crystal parameters are a = 10.2619(3) Å, b = 13.6776(3) Å, c = 10.9318(3), β = 116.640(4)° for the former while a = 13.0012(1) Å, b = 14.9692(1) Å, c = 14.1178(1) Å, β = 97.101(1)° for the latter. In both compounds, the aryl group and the triazole moieties are twisted from one another. The twist angle is 84.75˚for 4a while 86.64˚ for 4b. Based on Hirshfeld calculations, the Cl…H, O…H, N…H and C…H non-covalent interactions in 4a while the O…H interactions in 4b are the most important. The molecular mechanism of the key 32CA reaction between the in situ generated azomethine ylides and the corresponding chalcones has been studied within the Molecular Electron Density Theory (MEDT). The MEDT study reveals that the low activation energies and high experimental selectivity are the result of the supernucleophilic character of the ylides and the strong electrophilicity of the chalcones, which favour the process through a high polar character. This high polar character accounts for the total endo selectivity experimentally found.
Application of nucleophilic substitution reaction for sensitive determination of heptaminol hydrochloride in pharmaceuticals
Abdelgaleel M, Nagi DM, Oraby M, Derayea SM and Khashaba PY
A straightforward and sensitive spectrofluorimetric approach was established for the determination of heptaminol hydrochloride (HTM-HCl) based on the derivatization of the drug through its reaction with 5-dimethylaminonaphthalene-1-sulfonyl chloride (Dansyl chloride). The reagent underwent a nucleophilic substitution of its chlorine atom with HTM to give N-(5-dimethylaminonaphthalene-1-sulfonyl)-6-amino-2-methylheptan-2-ol. The highly luminescent derivative was extracted using methylene chloride and subjected to analysis at an excitation wavelength of 345 nm and an emission wavelength of 490 nm. The chemical reaction occurred within an aqueous environment buffered with a 0.1 M borate buffer solution adjusted to pH 10.5. Experimental findings indicate that the proposed method displays sensitivity and linearity across a concentration range from 0.03 to 2 µg mL. The method achieves lower detection and quantification limits of 0.016 and 0.048 µg mL, respectively. The analytical validation of this method followed the guidelines outlined by the International Council of Harmonization (ICH). This approach was applied effectively for quantifying the medication in both tablet and oral drops formulations available on the market, demonstrating excellent recovery of 98.95 ± 0.45 for tablets and 99.37 ± 0.24 for oral drops with no interference from excipients.
Bio-inspired one-pot synthesis of luminescent silver nanoparticles and its significant utility as a fluorescence nano sensor for analysis of two adjunctive COVID-19 drugs
Mostafa YE, Elsebaei F and Metwally ME
This study reveals one-step green synthesis of plant inspired silver nanoparticles (Ag-NPs). The synthesis procedure relies on the bio-reduction of Ag to Ag using orange waste (orange peel) extract as cheap, readily available, sustainable, biocompatible feedstocks as a reducing and stabilizing agent. The prepared Ag-NPs passed through a full characterization procedure for better confirmation and elucidation of optical and structural properties. The fluorescence of the prepared Ag-NPs has a quantum yield of 17.15% enabling its potential use in chemical sensing of drugs. Ag-NPs are conceived to be used as a fluorescent nano sensor for sensitive, ecofriendly, rapid spectrofluorimetric determination of two recent direct oral anticoagulants, namely, rivaroxaban (RIV) and edoxaban tosylate monohydrate (EDT); COVID-19 adjunctive drugs in their raw materials and pharmaceutical tablets. The fluorescence of the prepared Ag-NPs at 333 nm was found to be substantially quenched in existence of increasing concentrations of each drug. The quenching mechanisms were studied and explained. The validation of the method revealed linear correlation over the ranges of 0.5-10 µg/ml with an excellent regression correlation (r = 0.9999) for both drugs with minimum detection limits of 0.14 and 0.16 µg/ml for rivaroxaban and edoxaban tosylate monohydrate, correspondingly. Three different metrics were employed for verifying the greenness profile of the presented study. The findings of the greenness assessment were congruent and compatible with the green synthesis procedure, ecofriendly analysis, and the exclusion of using organic solvents and noxious materials opening an avenue for green synthesis of nanoparticles instead of chemical and physical methods.
Sustainable and efficient monitoring of tryptophan and tyrosine serum levels: a green HPTLC method as a biomarker for type 2 diabetes
Kamel RM, Abdel-Aal FAM, Mohamed FA and Mohamed AI
In recent years, there has been considerable interest in using amino acids like tryptophan (Trp) and tyrosine (Tyr) as biomarkers for various diseases, including type 2 diabetes mellitus (T2D). In diseases like T2D, the metabolism of Trp and Tyr is altered. The activity of enzymes involved in Trp metabolism increases, leading to a decrease in its serum level. On the other hand, the serum level of Tyr increases due to the suppressed activity of its metabolizing enzymes. These observations suggest that Trp and Tyr metabolism may play a crucial role in the pathophysiology of type 2 diabetes. Our study highlights the potential utility of Trp and Tyr as biomarkers for the early detection, prognosis, and monitoring of this metabolic disorder. Given these observations, we aimed to develop a high-performance thin-layer chromatographic (HPTLC) method that is sensitive, selective, rapid, and environmentally friendly for estimating the concentrations of Trp and Tyr in biological fluids, particularly serum samples. To evaluate the method, we performed analysis using serum samples from controlled and streptozotocin-induced diabetic rats. Our main objective was to develop a method that is sensitive and selective for precisely determining Trp and Tyr serum levels, which could serve as potential biomarkers for T2D. Fluorescence and absorption modes were employed for densitometry scanning. We assessed the precision and high separation efficiency of the chromatographic system by calculating parameters such as separation and resolution factors, number of theoretical plates, and height equivalent to theoretical plates. To evaluate the environmental impact of our proposed method, we employed the AGREE (Analytical GREEnness metric) and GAPI (Green Analytical Procedure Index) greenness assessment tools. The results confirmed that our method is environmentally friendly and exhibits superior eco-friendliness and greenness compared to other reported methods.
Decoding the synergy: unveiling gradient boosting regression model for multivariate quantitation of pioglitazone, alogliptin and glimepiride in pure and tablet dosage forms
Elkhoudary MM, Marie AA, Hammad SF, Salim MM and Kamal AH
This study represents a comparison among the performances of four multivariate procedures: partial least square (PLS) and artificial neural networks (ANN) in addition to support vector regression (SVR) and extreme gradient boosting (XG Boost) algorithm for the determination of the anti-diabetic mixture of pioglitazone (PIO), alogliptin (ALG) and glimepiride (GLM) in pharmaceutical formulations with aid of UV spectrometry. Key wavelengths were selected using knowledge-based variable selection and various preprocessing methods (e.g., mean centering, orthogonal scatter correction, and principal component analysis) to minimize noise and improve model precision. XG Boost effectively enhanced computing speed and accuracy by focusing on specific spectral features rather than the entire spectrum, demonstrating its advantages in resolving complex, overlapping spectral data. The independent test results of different models demonstrated that XG Boost outperformed other methods. XG Boost achieved the lowest root mean squared error of prediction (RMSEP) and standard deviation (SD) values across all compounds, indicating minimal prediction error and variability. For PIO, XG Boost recorded an RMSEP of 0.100 and SD of 0.369, significantly better than PLS and ANN. For ALG, XG Boost showed near-perfect performance with an RMSEP of 0.001 and SD of 0.005, outperforming SVR and PLS, which had higher error rates. In the case of GLM, XG Boost also excelled with an RMSEP of 0.001 and SD of 0.018, demonstrating superior precision compared to the much higher errors seen in PLS and ANN. These results highlight XG Boost's exceptional ability to handle complex, overlapping spectral data, making it the most reliable and accurate model in this study.