BMC Chemistry最新文献

Multimodal analgesia and rational polypharmacy have emerged as modern pain management strategies, offering synergistic pain relief while mitigating the adverse effects of high-dose monotherapy. A novel antinociceptive fixed-dose combination tablet containing tramadol, ibuprofen, and caffeine exemplifies this approach by integrating a centrally acting weak opioid tramadol, a peripherally acting nonsteroidal anti-inflammatory drugs ibuprofen, and a central nervous system stimulant adjuvant caffeine into a single formulation. In the present work, the first HPLC method for the concurrent quantification of tramadol, ibuprofen and caffeine in bulk powder and tablet dosage forms was developed and validated to support the quality control of this innovative multimodal analgesic fixed-dose combination. The optimal chromatographic separation was achieved using a Zorbax SD-C8 column (150 × 4.6 mm, 5 µm) as the stationary phase. The mobile phase was composed of acetonitrile: 0.01 M phosphate buffer pH 5.0 (35.0: 65.0, v/v), delivered at a flow rate of 1.0 mL/min with UV detection at 220.0 nm. The separation was achieved within 8.0 min, with linearity ranges of 1.0–45.0 μg/mL for tramadol, 1.0–25.0 μg/mL for ibuprofen, and 1.0–30.0 µg/mL for caffeine. The suggested method was validated according to the ICH guidelines and successfully utilized for the quantitative determination of tramadol, ibuprofen and caffeine in bulk powder, laboratory-prepared mixtures and pharmaceutical formulation. The proposed method exhibited outstanding performance for determination of the three cited drugs, characterized by high accuracy (ranging from 100.42% to 100.82%) and excellent precision (< 2% RSD). The sustainability profile of the method was assessed using the Analytical eco-scale, Analytical GREEnness metric, Green analytical procedure index, Blue Applicability Grade Index, White analytical chemistry, and Violet Innovation Grade Index to evaluate the sustainability, applicability, and innovative potential of the proposed method. The method combines analytical rigor, operational simplicity, and sustainable design, setting a new benchmark for analytical support of rational polypharmacy products.

The goal of the current work was to create and validate a quick, sensitive, and environmentally friendly reverse-phase “high-performance thin-layer chromatography (HPTLC)” approach for the simultaneous measurement of rosuvastatin (ROS) and clopidogrel (CLOP) in their fixed-dose combination (FDC) capsules. Eight different greenness and whiteness tools, such as the analytical eco-scale (AES), chloroform toxicity (ChlorTox), the analytical GREEnness (AGREE), the modified green analytical procedure index (MoGAPI), the complex MoGAPI, the blue applicability grade index (BAGI), the carbon footprint reduction index (CaFRI), and the click analytical chemistry index (CACI) were utilized to evaluate the method's greenness and whiteness profiles. The suggested strategy was linear for both medications in the 25–1000 ng/band level. The method was proven to be reliable, sensitive, accurate, precise, and eco-friendly. The results of greenness and whiteness tools, such as AES (87), ChlorTox (0.86 g), AGREE (0.72), MoGAPI (85), complex MoGAPI (90), BAGI (77.5), CaFRI (89), and CACI (91) demonstrated that the current method had the unparalleled greenness and whiteness profiles. Using the proposed methodology, it was found that the assay of CLOP and ROS in FDC products A and B was ranged from 98.41 to 101.02%. These results confirm that the suggested approach is appropriate for concurrently analyzing ROS and CLOP. The work's findings showed that the suggested approach might be used to consistently analyze CLOP and ROS in commercial dosage forms.

A novel heterocyclic Schiff base ligand, {2,2′-((4-chloro-1,3-phenylene)-bis(oxy))bis-(N′-((E)-(1 H-benzo[1-3]-triazole-1-yl)methylene)acetohydrazide)}, was synthesized and coordinated with Co(II) and Zn(II) chlorides to yield two metal complexes. The ligand and complexes were analyzed using FT-IR, ¹H and ¹³C NMR, UV-visible spectroscopy, and mass spectrometry, which provided spectral shifts typical of coordination involving the imine nitrogen and amide carbonyl groups. DFT calculations (B3LYP/LanL2DZ) showed that complexation decreased the energy gap between HOMO and LUMO from 4.26 eV (free ligand) to 3.18 eV and 2.66 eV for Zn(II) and Co(II) complexes, respectively, showing increased chemical reactivity. Similarly, the electrophilicity index increased to 33.81 eV for the Zn complex and 40.97 eV for the Co complex, indicating increased electron-accepting ability and potential biological activity. Thermal decomposition of Zn and Co complexes yielded ZnO NPs (mean crystallite size 35.6 nm) and Co₃O₄ NPs (33.8 nm), as evidenced by powder X-ray diffraction (XRD) and transmission electron microscopy (TEM). Antibacterial activity against Gram-positive bacteria (Staphylococcus aureus, Bacillus subtilis) and Gram-negative bacteria (Escherichia coli, Pseudomonas aeruginosa) was found to show that ZnO NPs had the largest inhibition zones (up to 28 mm), followed by metal complexes [Zn(L)]Cl₂ and [Co(L)]Cl₂, whereas the free ligand had very poor activity (only inhibition zones of 11–13 mm).

Prolonged exposure to ultraviolet (UV) irradiation and microbial contamination correlated to the environmental pollution and ozone layer depletion caused serious health concerns. Nanotechnology offers promising solutions in functional textiles, particularly through nanoparticles with high surface energy, ionization capacity, and surface area. Herein, for the first time the exploitation of infra-red irradiation for controllable nucleation of PdNPs was investigated. This study is considered with the enhancement of UV protection and antimicrobial properties of viscose fabrics via infrared (IR)-assisted/in-situ self-clustering of palladium nanoparticles (PdNPs). PdNPs were synthesized within viscose matrix under varying conditions: two concentrations of PdCl₂ (100 and 200 mM), two pH levels (2.0 and 12.0), and before/after cationization using DADMAC. SEM and EDX analyses confirmed the deposition and elemental composition of nanoparticles. Particle size before cationization ranged from 7.8 ± 2.5 to 11.1 ± 2.5 nm, and 5.5 ± 1.7 to 2.4 ± 0.7 nm. Acidic media and DADMAC treatment is favored for smaller, spherical particles and better dispersion. After PdNPs modification, viscose showed very good – excellent UV-protection (UPF = 35.2–88.0). Excellent antimicrobial activity (microbial reduction = 90.5–94.3%) was obtained for modified viscose against different microbial pathogens. Multi-functional of viscose was prepared with good durability. The data demonstrate that, IR-assisted PdNPs functionalization is an effective and sustainable method for durable multi-performance viscose textiles.

The availability and supply of potable water remains elusive especially in low-income economies with attendant life-threatening health risks. Moringa oleifera seed proteins have been reported to possess water purification activity; thus, there is a need to prepare the proteins in a useable, sustainable, and readily acceptable manner through nanotechnology. This work is aimed at developing, characterizing, and evaluating nanoemulsions loaded with proteins extracted from M. oleifera seeds for water purification. Various batches of nanoemulsions were formulated by spontaneous emulsification and their globule sizes, morphology, pH, viscosity, and protein encapsulation efficiency were determined. In vitro release of M. oleifera protein from the nanoemulsions and the stability profile of the formulations were investigated. Water quality parameters endorsed by the WHO including coagulation efficiency, pH, total dissolved solids, alkalinity level, and total coliform number were estimated following treatment of water samples with the nanoemulsions. Formulation globules had nanometric size range (103–212 nm), were morphologically spherical, had pH range of 6.71–7.23, were a Newtonian system, recorded 90% protein encapsulation efficiency, had sustained release character, and had acceptable stability especially when stored at 27 °C. Protein-loaded nanoemulsions showed good coagulation activity with about 97% efficiency. Treated water recorded pH, temperature, alkalinity, and conductivity within acceptable limits, and contained very low dissolved solids and total coliform count. In conclusion, the study highlighted the efficiency of nanoemulsions containing M. oleifera seed proteins as biocoagulants for water purification.

The global decline in fossil fuel availability and rising environmental concerns have intensified the search for sustainable alternative fuels, with biodiesel emerging as a promising option. This study investigates the performance, combustion, and emission characteristics of a B20 biodiesel blend derived from Used Temple Oil Methyl Ester (UTOME) enhanced with cerium oxide (CeO₂) nano additives. Conducted at constant speed and varying engine loads, the experiments show that CeO₂ additives significantly enhance brake thermal efficiency (BTE), with the B20UTOME100CeO₂ blend achieving efficiency levels comparable to pure diesel. Specific fuel consumption (SFC) decreases as CeO₂ concentration increases, reflecting enhanced fuel efficiency, while higher cylinder pressure (CP) and net heat release (NER) signify improved combustion processes. Emission analysis reveals substantial reductions in hydrocarbons (HC), carbon monoxide (CO), and nitrogen oxides (NO_x), with the B20UTOME100CeO₂ blend demonstrating the lowest HC and NO_x emissions due to better fuel atomization, improved combustion efficiency, and lower peak combustion temperatures enabled by the CeO₂ nanoparticles. The B20UTOME100CeO₂ blend demonstrated enhanced performance at maximum load, exhibiting a 1.57% increase in Brake Thermal Efficiency, a 6.67% reduction in Specific Fuel Consumption, a 2.83% elevation in cylinder pressure, and a 5.95% greater heat release when compared to conventional diesel. Emissions analysis revealed a significant reduction in carbon monoxide by 66.67%, hydrocarbons by 13.51%, and nitrogen oxides by 0.20% relative to diesel. A gradient boosting regressor model was trained on experimental data comprising fish oil biodiesel blends with nanoparticle additives, utilizing Python libraries. The accuracy of the model is supported by a mean squared error of 0.7647 for HC emissions and R² scores of 0.9247 and 0.9882 for HC and NO_x emissions, respectively. Overall, the results indicate that B20UTOME with 100 ppm CeO₂ additives offers a viable alternative to diesel, providing improved thermal efficiency, enhanced combustion, and reduced harmful emissions. The marked reduction in toxic emissions, including CO, HC, and NO_x, carries significant biomedical relevance. These pollutants are known to induce respiratory, cardiovascular, and neurological disorders upon prolonged exposure. Therefore, implementing CeO₂-enhanced biodiesel blends offers a potential strategy for protecting public health by diminishing harmful exhaust emissions.

In the oil and gas industry, carbon steel is widely used but suffers from severe corrosion in acidic environments, particularly in the presence of CO₂ and H₂S. This study presents the synthesis and evaluation of a novel eco-friendly compound, 2,2′-(4,6-dihydroxyisophthaloyl) bis(N-phenylhydrazine-1-carbothioamide) (DICA), as an effective corrosion inhibitor for low-carbon steel in 0.5 M HCl solution. Structural characterization was confirmed through NMR, elemental analysis, and mass spectrometry. The corrosion inhibition performance was investigated using weight loss (WL), potentiodynamic polarization (PDP), and electrochemical impedance spectroscopy (EIS). DICA demonstrated outstanding inhibition efficiency, reaching 91.41% at 300 ppm concentration and 298 K, indicating a strong concentration-dependent protective effect. Surface morphology analysis by SEM and AFM revealed a significant reduction in steel surface roughness and corrosion damage due to DICA adsorption. Complementary density functional theory (DFT) calculations and Monte Carlo simulations corroborated the mixed-mode adsorption mechanism involving both chemisorption and physisorption. These findings confirm the potential of DICA as a high-performance, environmentally benign inhibitor for protecting carbon steel in aggressive acidic media.

Global urbanization is driving high volumes of agricultural and food waste, creating an urgent need for sustainable and effective technologies to convert biomass into valuable products. This study explores the conversion of palm waste into cellulose microfibers (CMF) using Ammonia Fiber Expansion (AFEX) followed by acid hydrolysis, with a focus on structural characterization, thermal stability, and reaction kinetics compared to raw material. The resulting CMF exhibited elongated, uniform fibers with smooth surfaces, with lengths of 0.1–3.0 mm, and diameters of 5–20 μm. X-ray analysis revealed a significant increase in the carbon/oxygen ratio, from 1.8 ± 0.2 in raw palm leaves to 2.7 ± 0.3 in CMF, indicating enhanced carbon content due to dehydration and reduction of carbonyl groups. FTIR spectra confirmed effective removal of lignin and hemicellulose after treatment, further supporting this chemical transformation. Thermal analysis demonstrated that CMF possesses higher heat content than raw leaves, suggesting its potential for energy-related applications. TGA showed that CMF decomposes at slightly higher temperatures, indicating improved thermal stability. Isoconversional kinetic analysis using the Vyazovkin Nonlinear (NLN) and Kissinger-Akahira-Sunose (KAS) methods revealed variable effective activation energies (E_α), consistent with a complex degradation mechanism. Overall, CMF displayed lower E_α values than raw biomass, especially at early and mid-reaction stages. Kinetic modeling at 50% conversion showed a markedly higher pre-exponential factor (A_α) for raw leaves (2.8 × 10¹³ s⁻¹) compared to CMF (7.4 × 10⁹ s⁻¹), reflecting structural alterations from treatment. Both raw and CMF samples exhibited negative activation entropy (ΔS^≠) values of − 237.7 and − 240.3 J mol⁻¹ K⁻¹, respectively, suggesting greater molecular order in activated complexes. The enthalpy of activation (ΔH^≠) was 149.7 ± 3.9 kJ mol⁻¹ for raw leaves versus 120.4 ± 3.9 kJ mol⁻¹ for CMF, Gibbs free energy of activation (ΔG^≠) was slightly higher for raw leaves (297.0 ± 3.9 kJ mol⁻¹) compared to CMF (269.4 ± 3.9 kJ mol⁻¹), primarily due to differences in ΔH^≠. These kinetic parameters are crucial for any future implementation of palm leaves conversion into CMF at the industrial scale.

Titanium dioxide is used in different applications such as paints, plastics, paper, and water treatment. Various routes are applied for the recovery of TiO₂ according to the available raw material. The aim of this work is the application of response surface methodology for optimizing the recovery of TiO₂ from illeminite beach sand deposits (black sand, Kafr-El-Sheikh, Egypt) with high purity using sulfuric acid. Utilizing local raw material to obtain titanium dioxide with high purity for applications in paints and energy applications. Applying a simple method for separating iron, which is present in high weight% (49%). Application of the RSM approach in the extraction of titanium dioxide to determine the interaction of the studied parameters and determine the model relating them to the yield of titanium dioxide. characterizations of raw material are applied; X-ray fluorescence (XRF) indicates the chemical composition, and the weight% of titanium dioxide is 43%. The illeminite phase is confirmed by X-ray diffraction (XRD) of the raw material sample. The average particle size of illeminite powder is measured using screen analysis, and it is around 118 micrometers. Three selected parameters affecting the leaching of illeminite are studied using the Response Surface Methodology (RSM) technique: temperature (60–120℃), sulphuric acid concentration (4–12 M), and time (1–5 h). Maximum conversion (84%) is obtained at the optimum conditions predicted by the RSM model at Temperature (120 ℃), time 4.2 h, Concentration (12 M). The relation between the studied parameters and conversion is represented by a reduced cubic model with R² = 0.973 and p-value = 0.0001, which confirms the accuracy of the model. The prepared titanium dioxide is separated from the filtrate solution by hydrolysis at 109 °C for 3 h, using EDTA as a complexation agent to capture the solvated iron. The hydrated titanium dioxide powder is dried, then calcinated at 500 °C for 3 h to produce titanium dioxide in an anatase phase. The prepared sample is examined using XRF, XRD, and SEM-EDX. 96.4% purity of titanium dioxide is formed; the XRD pattern of the examined sample confirmed the formation of the anatase phase. SEM images display that TiO₂ has a uniform spherical morphology. The EDX spectrum shows that most of the sample is TiO₂. The average particle size of the prepared titanium dioxide using a particle size analyzer is about 78.82 nm.

In this paper molecular interactions of L-glutamic acid (Glu) in aqueous D-sorbitol (D-SOR) are analyzed by measuring electrical conductivity in the broad temperature range of 293.15–313.15 K at ambient pressure. The density and viscosity data were also measured experimentally required to explore the derived conductometric properties. Meanwhile, the molar conductance ((:{{Lambda:}}_{text{m}})), limiting molar conductance(:{:({Lambda:}}_{text{m}}^{0})), Walden product (( Lambda _{{text{m}}}^{0} eta _{0} )), ion association constants ((:{text{K}}_{text{A}})) and activation energy ((:{text{E}}_{text{A}})) of ion association are derived and discussed in the light of ion-ion and ion-solvent interactions. The Kraus–Bray model was used to analyze the limiting molar conductance ((:{{Lambda:}}_{text{m}}^{0})) of the solutions. For the mixtures under study, the increased (:{{Lambda:}}_{text{m}}) values for Glu in aqueous D-SOR compared to pure water suggest a synergistic interaction. As D-SOR concentration increases, (:{{Lambda:}}_{text{m}}) of Glu decreases due to stronger solute–cosolute interactions and reduced ion dissociation. Glu functions as a structure creator in water, according to the ( Lambda _{{text{m}}}^{0} eta _{0} ) finding. However, in aqueous D-SOR, increasing temperature and D-SOR concentration cause ( Lambda _{{text{m}}}^{0} eta _{0} ) to drop, indicating structure-breaking behavior. Numerous energy and environmental applications may benefit from an investigation of the conductometric properties of Glu and D-SOR in aqueous solutions.