Fourier Transform Infrared Spectroscopy Studies Research Articles

Surface Acidic Species-Driven Reductive Amination of Furfural with Ru/T-ZrO2.

Catalyst development for upgrading bio-based chemicals towards primary amines has increasingly attracted owing to their applications in the pharmaceutical and polymer industries. The surface acidic sites in metal oxide-based catalysts play a key role in the reductive amination of aldehydes/ketones involving H2 and NH3; however, the crucial role of the type of surface acidic species and their strength remains unclear. Herein, this study exhibits the catalytic reductive amination of furfural (FUR) to furfurylamine (FUA) with Ru supported on tetragonal (Ru/T-ZrO2) and monoclinic (Ru/M-ZrO2) ZrO2. Ru/T-ZrO2 exhibited an 11.8-fold higher rate of reductive amination than Ru/M-ZrO2, giving a quantitative yield of FUA (99%) at 80 °C in 2.5 h and is recyclable up to four runs. Catalyst surface investigation using spectroscopic techniques, like X-ray photoelectron, electron paramagnetic resonance, and Raman, confirm higher oxygen vacancy sites (1.6 times) on the surface of Ru/T-ZrO2 compared to Ru/M-ZrO2. Moreover, in-situ NH3-diffuse reflectance infrared Fourier transform spectroscopy studies display that Ru/T-ZrO2 has more moderate Bronsted acidic sites (surface H-bonded hydroxyl groups) than Ru/M-ZrO2. Further, the controlled experiments and poisoning studies with KSCN and 2,6-lutidine suggest the crucial role of Ov sites (Lewis acidic sites) and surface hydroxyl groups (Bronsted acidic sites) for selective FUA formation.

Optimization and Transfollicular Delivery of Finasteride Loaded PLGA Nanoparticles Laden Carbopol Gel for Treatment of Hair Growth Stimulation

Background: One of the frequent side effects of cancer treatment is chemotherapyinduced alopecia (CIA). The psychological discomfort of hair loss may cause patients to stop receiving chemotherapy, lowering the therapy's effectiveness. Finasteride (FNS), a JAK inhibitor, has shown tremendous promise in therapeutic uses for treating baldness. Still, systemic side effects constrained its broad use in alopecia from oral treatment and a low absorption rate at the target site— PLGA-loaded nanoparticles (NPs) for topical delivery of FNS—to overcome these issues. Methods: The nano-precipitation process was used to make FNS-NPs. The independent variables (stabiliser and polymer) were PLGA (X1), P407 (X2), and sonication time (X3). Based on the point prediction method obtainable by the Box Behnken design software, the best FNS-NPs composition was selected. Entrapment efficiency, particle size, zeta potential, and polydispersity index were used to characterize the nanoparticles. Using Carbopol as a polymer, the ideal FNS-NPs composition was further transformed into a gel formulation. The prepared topical gel formulation (FNS-NPs gel) included gel characterization, Dynamic Light Scattering (DLS), Scanning Electron Microscopy (SEM), Powder X-ray Diffraction (PXRD), Differential Scanning Calorimetry (DSC), Fourier Transform Infrared Spectroscopy (FTIR), invitro and in vivo studies. Results: Optimized FNS-NPs (F13) had particle sizes of 175.26±3.85 nm, 0.241±0.11 PDI, 71.04±1.35 % EE, and -33.27±0.39 surface charges. There is no interaction between the drug and the excipients, according to FTIR studies. The FNS were visible in the X-ray diffractogram enclosed in a polymer matrix. The developed FNS-NPs gel formulation shows ideal drug content, viscosity, pH, and spreadability. According to the release and permeation investigation findings, FNS released slowly (68.73±0.94%) but significantly permeated the membrane more than before. In a dose- and time-dependent manner, the produced nanoparticles considerably (p≤0.05) increased FNS delivery compared to the FNS solution. The FNS-NPs gel therapy significantly increases the quantity and size of hair follicles dose-dependently. The effectiveness of the 1% FNSNPs gel and the 2% minoxidil solution were comparable. After 72 hours, the FNS-NPs gel showed no signs of skin irritation. The outcomes, therefore, showed that the trans follicular delivery mechanism of the FNS-NPs gel might stimulate hair growth. Conclusion: These findings imply that the innovative formulation that has been developed has several beneficial properties that make it suitable for FNS dermal delivery in the treatment of alopecia areata

Thermally stable high-loading single Cu sites on ZSM-5 for selective catalytic oxidation of NH3

Rigorous comparisons between single site- and nanoparticle (NP)-dispersed catalysts featuring the same composition, in terms of activity, selectivity, and reaction mechanism, are limited. This limitation is partly due to the tendency of single metal atoms to sinter into aggregated NPs at high loadings and elevated temperatures, driven by a decrease in metal surface free energy. Here, we have developed a unique two-step method for the synthesis of single Cu sites on ZSM-5 (termed CuS/ZSM-5) with high thermal stability. The atomic-level dispersion of single Cu sites was confirmed through scanning transmission electron microscopy, X-ray absorption fine structure (XAFS), and electron paramagnetic resonance spectroscopy. The CuS/ZSM-5 catalyst was compared to a CuO NP-based catalyst (termed CuN/ZSM-5) in the oxidation of NH3 to N2, with the former exhibiting superior activity and selectivity. Furthermore, operando XAFS and diffuse reflectance infrared Fourier transform spectroscopy studies were conducted to simultaneously assess the fate of the Cu and the surface adsorbates, providing a comprehensive understanding of the mechanism of the two catalysts. The study shows that the facile redox behavior exhibited by single Cu sites correlates with the enhanced activity observed for the CuS/ZSM-5 catalyst.

Multifiller-based polymer composites for shielding high energy ionising radiation.

Polydimethyl silicone rubber-based polymer composites filled with molybdenum and bismuth were fabricated using simple open mold cast technique. The physical and chemical structure and gamma shielding parameters like attenuation coefficient, half-value layer (HVL) thickness and relaxation length have been investigated for the said novel materials using X-ray diffraction (XRD), Fourier transform Infrared spectroscopy (FTIR) and gamma ray spectrometer. XRD study reveals the crystalline nature of the composites. It is evident from FTIR studies that there is no chemical interaction between the polymer matrix and filler particles. The results of attenuation studies reveal that the linear attenuation coefficient increases with addition of Bi and Mo and is found to be 0.653, 1.341 and 1.017, 1.793 and 0.102, 0.152cm-1 for 1MMB and 2MMB polymer composites at 80, 356 and 662keV gamma rays, respectively. The HVL thickness of the materials is found to be 1.06, 0.51 and 0.68, 0.38 and 6.73, 4.532cm for 1MMB (20Mo+10Bi phr) and 2MMB (40Mo+20Bi phr) at these energies, respectively. The mass attenuation coefficient of the novel composites 1MMB and 2MMB is found to be higher than the conventional materials like lead and barite for 356keV gamma rays. In addition, the material is found to be light weight and flexible enabling to be molded in required forms, thus being a substitute for the material lead that is known to be heavy and toxic by nature.

Engineering Lewis-Acid Defects on ZnO Quantum Dots by Trace Transition-Metal Single Atoms for High Glycerol-to-Glycerol Carbonate Conversion.

Efficient conversion of biomass wastes into valuable chemicals has been regarded as a sustainable approach for green and circular economy. Herein, a highly efficient catalytic conversion of glycerol (Gly) into glycerol carbonate (GlyC) by carbonylation with the commercially available urea is presented using low-cost transition metal single atoms supported on zinc oxide quantum dots (M1-ZnO QDs) as a catalyst without using any solvent. A facile one-step wet chemical synthesis allows various types of metal single atoms to simultaneously dope and introduce Lewis-acid defects in the ZnO QD structure. It is found that doping with a trace amount of isolated metal atoms greatly boosts the catalytic activity with Gly conversion of 90.7%, GlyC selectivity of 100.0%, and GlyC yield of 90.6%. Congruential results from both Density Functional Theory (DFT)and in situ Diffuse Reflectance Infrared Fourier Transform Spectroscopy (in situ DRIFTS) studies reveal that the superior catalytic performance can be attributed to the enriched Lewis acid sites that endow optimal adsorption, formation of the intermediate for coupling between urea and Gly, and desorption of GlyC. Moreover, the tiny size of ZnO QDs efficiently promotes the accessibility of these active sites to the reactants.

[Mg(H2O)4][(VO)2(PO4)2]: Crystal structure, DFT calculations, and catalytic activity

[Mg(H2O)4][(VO)2(PO4)2] has been successfully synthesized in the M2+-V4+-P-O system through hydrothermal synthesis route. It was characterized using single-crystal X-ray diffraction, Fourier Transform Infrared Spectroscopy (FT-IR), scanning electron microscopy (SEM), and thermal stability analysis (TG-DTA). [Mg(H2O)4][(VO)2(PO4)2] crystallizes in the tetragonal system (S.G.: I4/m), with the cell parameters: a = 6.2497(3), b = 6.2497(3), c = 13.4194(8) Å, V = 524.145 Å3, and Z = 2. The structure consists of vanadyl phosphate layers [VO(PO4)]2∞, constructed from O-vertices sharing [VO5]-square pyramids and [PO4] tetrahedral, which are separated by layers of [MgO6] octahedral linked to [VO5] by Mg–O–V bonds along c-axis. FT-IR and Raman studies confirmed the characteristic bands of phosphate and the vanadium (IV) groups. Thermogravimetric analysis of the compound was also used to study its thermal behavior. Furthermore, the catalytic efficiency of the title compound in the reduction by NaBH4 of three nitrophenol isomers (ortho-, meta-, and para-) to their corresponding aminophenols was tested. All three nitrophenol isomers could be reduced in 30 s in the presence of the title compound. First-principles calculations employing density functional theory (DFT) explored the structural, electronic, and optical properties. These computations were utilized to analyze the band structure, density of states, reflectivity, absorption coefficient, refractive index, and extinction coefficient. Examining the band structure and density of states (DOS) reveals that the material possesses a band gap of 2.79 eV.

Characterization of natural cellulosic fiber extracted from Grewia ferruginea plant stem

The use of natural fibers as reinforcement in polymer composites has gained significant attention due to their eco-friendly, and biodegradability. This study aims to extract and characterize the natural cellulosic fibers from the Grewia ferruginea stem. The fibers were extracted from plant stems using sodium hydroxide and analyzed using Fourier Transform infrared spectroscopy (FTIR) to determine chemical bonds on the fiber and functional group and Thermos-gravimetric analysis (TGA) was used to determine the thermal stability and degradation temperature of the fiber. The crystalline properties of extracted fibers were characterized by x-ray diffraction and surface morphology was characterized by Scanning electron microscopy. The chemical composition of the fibers, including cellulose, hemicellulose, lignin, moisture, extractive content, and fiber linear density, was evaluated. Tensile, thermal, and FTIR studies were conducted to assess the performance properties of the extracted fiber. The analysis revealed that the Grewia ferruginea fibers contain cellulose (60.4–72.6 wt%), hemicellulose (18.5 ± 3.1 %), and lignin (13.55 ± 2.75 %). The extracted fibers have a crystallinity index of 48.76 % and crystallite size of 5.14 nm. The fiber exhibited tenacity, breaking elongation, and Young's modulus values of (52.3 ± 6.5 cN/tex), (3.6 ± 1.8 %), and 43.5 ± 2.3 GPa, respectively. FTIR studies confirmed the presence of biopolymers in the Grewia ferruginea fiber. Additionally, the fibers demonstrated thermal stability up to 275 °C based on thermogravimetric analysis. These findings suggest that the extracted natural cellulosic Grewia ferruginea fiber has the potential to be used as a sustainable reinforcement material in polymeric composites.

Fabrication of silver nanoparticles synthesize using Lantana camara leaves extract on biofilm of sodium alginate

Silver nanoparticles (AgNPs) belong to the class of noble metal nanoparticles widely utilized across various sectors including biomedical applications, cosmetics, and everyday products like soaps, toothpaste, and detergents, thereby bringing individuals into direct contact with them. Extensive research has explored the antifungal properties of silver and silver nitrate. In this study, the synthesis of AgNPs was achieved effectively using a leaf extract from Lantana camara. Characterization of the synthesized AgNPs was performed employing transmission electron microscopy (TEM), scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). Analysis via UV–vis spectroscopy, SEM and TEM proved reliable and sufficient, with the appearance of AgNPs resulting in a noticeable change in tonal form. SPR peaks for AgNPs were observed at 467–473 nm using UV–Vis spectroscopy, while FTIR studies delineated the stabilizing and peak properties of the AgNPs. Size of the synthesized silver nanoparticles increased with higher concentrations of AgNO3 solution, albeit averaging on the smaller side of the nanometer scale. Synthesized AgNPs have effective antibacterial properties of nanoparticles, their incorporation into food packaging materials could enhance food storage lifespan and ensure consumer safety. The burgeoning interest in developing biodegradable coatings, as alternatives to costly wax-based coatings lacking biodegradability, is on the rise. These coatings aim to preserve the qualities of harvested crops. These are flexible films derived from biological compounds like proteins and polysaccharides, act as barriers against external elements and exhibit bioflexibility. They hold potential applications in medicine, pharmacology, and the food industry. The integration of polysaccharides, proteins, and lipids to enhance the functionality of films represents a recent advancement in the manufacturing of biodegradable and biofilm-based films. The anticipated outcome of this study is to augment the beneficial properties of Lantana camara for the preparation of nanoparticles using its extract, thereby highlighting its biological activity against emerging pathogenic biofilm-forming species.

In Situ Carbon-Confined MoSe2 Catalyst with Heterojunction for Highly Selective CO2 Hydrogenation to Methanol.

The synthesis of methanol from CO2 hydrogenation is an effective measure to deal with global climate change and an important route for the chemical fixation of CO2. In this work, carbon-confined MoSe2 (MoSe2@C) catalysts were prepared by in situ pyrolysis using glucose as a carbon source. The physico-chemical properties and catalytic performance of CO2 hydrogenation to yield methanol were compared with MoSe2 and MoSe2/C. The results of the structure characterization showed MoSe2 displayed few layers and a small particle size. Owing to the synergistic effect of the Mo2C-MoSe2 heterojunction and in situ carbon doping, MoSe2@C with a suitable C/Mo mole ratio in the precursor showed excellent catalytic performance in the synthesis of methanol from CO2 hydrogenation. Under the optimal catalyst MoSe2@C-55, the selectivity of methanol reached 93.7% at a 9.7% conversion of CO2 under optimized reaction conditions, and its catalytic performance was maintained without deactivation during a continuous reaction of 100 h. In situ diffuse infrared Fourier transform spectroscopy studies suggested that formate and CO were the key intermediates in CO2 hydrogenation to methanol.

Randomly Methylated β-Cyclodextrin Inclusion Complex with Ketoconazole: Preparation, Characterization, and Improvement of Pharmacological Profiles.

As a powerful imidazole antifungal drug, ketoconazole's low solubility (0.017 mg/mL), together with its odor and irritation, limited its clinical applications. The inclusion complex of ketoconazole with randomly methylated β-cyclodextrin was prepared by using an aqueous solution method after cyclodextrin selection through phase solubility studies, complexation methods, and condition selection through single factor and orthogonal strategies. The complex was confirmed by FTIR (Fourier-transform infrared spectroscopy), DSC (differential scanning calorimetry), TGA (thermogravimetric analysis), SEM (scanning electron microscope images), and NMR (Nuclear magnetic resonance) studies. Through complexation, the water solubility of ketoconazole in the complex was increased 17,000 times compared with that of ketoconazole alone, which is the best result so far for the ketoconazole water solubility study. In in vitro pharmacokinetic studies, ketoconazole in the complex can be 100% released in 75 min, and in in vivo pharmacokinetic studies in dogs, through the complexation, the Cmax was increased from 7.56 μg/mL to 13.58 µg/mL, and the AUC0~72 was increased from 22.69 μgh/mL to 50.19 μgh/mL, indicating that this ketoconazole complex can be used as a more efficient potential new anti-fungal drug.

Manufacturing and characterisation of 3D-printed sustained-release Timolol implants for glaucoma treatment.

Timolol maleate (TML) is a beta-blocker drug that is commonly used to lower the intraocular pressure in glaucoma. This study focused on using a 3D printing (3DP) method for the manufacturing of an ocular, implantable, sustained-release drug delivery system (DDS). Polycaprolactone (PCL), and PCL with 5 or 10% TML implants were manufactured using a one-step 3DP process. Their physicochemical characteristics were analysed using light microscopy, scanning electronic microscopy (SEM), differential scanning calorimetry (DSC) / thermal gravimetric analysis (TGA), and Fourier-transform infrared spectroscopy (FTIR). The in vitro drug release was evaluated by UV-spectrophotometry. Finally, the effect of the implants on cell viability in human trabecular meshwork cells was assessed. All the implants showed a smooth surface. Thermal analysis demonstrated that the implants remained thermally stable at the temperatures used for the printing, and FTIR studies showed that there were no significant interactions between PCL and TML. Both concentrations (5 & 10%) of TML achieved sustained release from the implants over the 8-week study period. All implants were non-cytotoxic to human trabecular cells. This study shows proof of concept that 3DP can be used to print biocompatible and personalised ocular implantable sustained-release DDSs for the treatment of glaucoma.

Physicochemical Investigation of Synthesized Bismuth and Silver-Doped Bismuth Nanoferrites, And Their Dielectric Properties

Bismuth nano ferrite and silver-doped bismuth nano ferrite are synthesized by the sol-gel method. The synthesized compound is characterized through several characterization methods such as the X-ray diffraction method, Fourier transform infrared spectroscopy (FTIR), Scanning electron microscopy (SEM), and UV-Visible spectral studies. The X-Ray diffraction confirms bismuth nano ferrite has a Rhombohedral structure and belongs to the R-3m space group, and the silver-doped bismuth nano ferrite has an orthorhombic structure and belongs to the Cmcm space group. The crystallite size is calculated through Scherrer’s formula, the bismuth nano ferrite has a crystallite size of 20 nm, and the silver-doped bismuth nano ferrite has a crystallite size of 36.33 nm. FTIR studies confirm the formation of ferrite and indicate the metal ion group observed the peak shift after doping in the fingerprint region. The metal ion peaks are presented at 446.7 cm−1 and 527.8 cm−1 but after doping they shifted to 453 cm−1, 534 cm−1. The UV-Visible spectral analysis identifies the change in the energy band gap through a tauc plot, initially the energy band gap of bismuth nano ferrite is about 2.79 eV but after doping it reduces to 1.61 eV. the surface morphology is determined by SEM analysis and it provides 30 nm and for the doped compound 37 nm average particle size. Dielectric study confirms doping of silver to the bismuth gives more improved results which will be helpful at the application level such as in memory devices, photocatalysis, water splitting, and gas detection.

Crocin-Phospholipid Complex: Molecular Docking, Molecular Dynamics Simulation, Preparation, Characterization, and Antioxidant Activity.

Crocin is a water-soluble carotenoid compound present in saffron (Crocus sativus L.), known for its wide range of pharmacological activities, including cardioprotective, hepatoprotective, anti-tumorigenic, anti-atherosclerosis, and anti-inflammatory effects. The instability of crocin, its low miscibility with oils, and poor bioavailability pose challenges for its pharmaceutical applications. This study aimed to design and prepare a crocin-phospholipid complex (CPC) and assess its physicochemical properties. The study investigated the formation of the complex and its binding affinity through molecular docking. Molecular dynamics (MD) simulations were conducted to find the optimal molar ratio of crocin to phospholipid for the complex's preparation. The CPC was produced using the solvent evaporation method. Techniques such as X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), field-emission scanning electron microscopy (FE-SEM), nuclear magnetic resonance (NMR), and solubility studies were utilized to characterize and confirm the formation of CPC. Additionally, the in vitro antioxidant activity of crocin and CPC was evaluated. Molecular dynamic simulations explored molar ratios of 1: 1, 1: 1.5, and 1: 2 for crocin to phospholipid. The ratio of 1: 2 was found to be the most stable, exhibiting the highest probability of hydrogen bond formation. Molecular docking, FTIR, and NMR studies indicated hydrogen bond interactions between crocin and phospholipid, confirming CPC's formation. XRD and FE-SEM analyses showed a decrease in crocin's crystallinity within the phospholipid complex. Furthermore, the solubility of crocin in n-octanol was enhanced post-complexation, indicating an increase in crocin's lipophilic nature. Phospholipid complexation emerges as a promising technique for enhancing the physicochemical characteristics of crocin.

NanoGuard: Antibacterial marvels of strontium titanate – Synthesis, characterization, and multifunctional insights

This study presents a comprehensive exploration into the synthesis and multifaceted characterization of strontium titanate (ST) nanopowder via the solution combustion method. The investigation delves into the photoluminescent properties, electrochemical behaviors assessed through potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy (EIS), as well as antibacterial characteristics of the synthesized nanoproduct. Through meticulous analysis involving powder X-ray diffraction (PXRD), Field emission scanning electron microscopy (FESEM), Transmission electron microscopy (TEM), Fourier-transform infrared spectroscopy (FT-IR), and UV–visible spectroscopy (UV–vis), ST nanoparticles revealed intriguing features. PXRD unveiled a cubic crystal structure with a crystallite size of ∼ 11 nm, showcasing a crystallinity of 89.23. FESEM, UV–visible spectroscopy, and FT-IR studies uncovered irregularities in size, band gap properties, and the formation of M−O bonds within ST, with an Eg value of ∼ 3.0 eV. Photoluminescence investigations highlighted oxygen deficiencies within the ST material. Furthermore, corrosion inhibition efficiency was evaluated, demonstrating a maximum of 81.9 % at a concentration of 400 ppm, while antibacterial studies exhibited promising results against both Gram-positive (Bacillus subtilis) and Gram-negative (Escherichia coli) bacteria, with zone of inhibitions (ZOI) measuring 8.00 ± 0.250 mm and 9.00 ± 0.000 mm, respectively. These findings collectively underscore the diverse potential applications of ST nanoparticles and offer valuable insights into their structural, optical, electrochemical, and antimicrobial properties.

Green route to prepare zinc oxide nanoparticles using Moringa oleifera leaf extracts and their structural, optical and impedance spectral properties

This article investigates biosynthesis of zinc oxide (ZnO) nanoparticles (NPs) from Moringa oleifera leaves extract using an eco-friendly preparation method. The crystalline structure, optical properties, morphology and impedance characteristics of ZnO NPs were analyzed using impedance spectroscopy, powder X-ray diffraction (XRD), scanning electron microscopy, Fourier transform infrared spectroscopy (FTIR) and ultraviolet spectroscopy (UV-vis). The powder XRD pattern confirmed the crystallinity of the prepared samples as well as enabled determining their crystallite size and pure phase portion. The FTIR study confirmed the presence of functional groups responsible for reduction metal ions into ZnO NPs. UV-vis absorption spectra contained the absorption peak corresponding to ZnO NPs. Impedance spectroscopy of the prepared ZnO NPs revealed the grain boundaries in them and confirmed their semiconducting nature.

SOLUBILITY ENHANCEMENT OF ATAZANAVIR BY HYDROTROPIC SOLUBILIZATION TECHNIQUE

Objective: The present study aims to increase the solubility and dissolution of atazanavir sulfate (ATZ) by employing a hydrotropic solubilization technique. Methods: ATZ is a poorly soluble drug classified under the biopharmaceutical classification system (BCS)-II, which accounts for its poor oral bioavailability. Different hydrotropic agents, such as urea and sodium benzoate and their combinations at different ratios were prepared. The prepared hydrotropes were systematically investigated for compatibility between the drug and excipients using Fourier Transform Infra-Red Spectroscopy (FTIR) and Differential Scanning Calorimetry (DSC) approaches. Further, in order to understand the conversion from crystalline to amorphous nature, X-ray Diffraction (XRD) and Scanning Electron Microscopy (SEM) studies were also performed. The formulation of a mixed hydrotropic mixture comprising urea (2.5% w/v) and sodium benzoate (5% w/v) exhibited a 100.35±1.7 % drug release at 0.25 h with higher dissolution efficiency as compared with other batches of individual hydrotrope, mixed hydrotropes as well as pure drug. Results: FTIR studies revealed that there is no incompatibility between the drug and the selected hydrotropes. DSC studies also confirmed the fact that there is no interaction between the drug and the hydrotropes by the disappearance of an endothermic peak. XRD studies revealed that there was a significant reduction in the intensity of peaks, indicating the conversion of crystalline to the amorphous form. The SEM studies indicated that the drug appears crystalline in the shape of an irregular tiny prismatic needle, indicating its crystallinity. At the same time, the hydrotrope mixtures appeared in agglomerated form with a porous nature, which may be accountable for its increase in solubility. The hydrotropes prepared using urea alone exhibited an increase in solubility of 4.42 folds, and the hydrotrope prepared using sodium benzoate alone exhibited an increase in solubility of 3.178 folds; the combination hydrotropes of urea and sodium benzoate exhibited an increase in solubility of 8.78 folds in water as compared to pure drug. The drug release from the mixed hydrotropes obeys zero-order kinetics with diffusion as the main mechanism. Conclusion: The present investigation concluded that the combination of hydrotropes enhanced the solubility of the aqueous soluble drug ATZ. However, in vivo studies are essential to establish its potential effect.

Selective recovery of copper from copper tailings and wastewater using chelating resins with bis-picolylamine functional groups

Industrial and mining wastewater, along with copper tailings, are typically highly acidic and contain copper and other heavy metals, which may contaminate and damage the environment. Copper (Cu) is, however, a valuable metal, making its removal and recovery from such wastewater and tailings environmentally and economically advantageous. Chelating ion exchange resins featuring bis-picolylamine functional groups are especially suitable for application requiring selective recovery of Cu(II) from highly acidic media. In this study, and for the first time, the kinetics, binding capacity and selectivity of Lewatit MDS TP 220 chelating resin towards Cu(II) are reported. The resin was characterized by Zeta potential, scanning electron microscope (SEM), Fourier-transform infrared spectroscopy (FTIR), and X-ray photoelectron spectroscopy (XPS). Factors including pH, initial concentration, contact time, temperature, and selectivity were investigated to assess the adsorption performance of the chelating resin. The adsorption kinetics tests revealed fast adsorption within the first 5–30 min and fitted the pseudo-second-order model, signifying chemisorption process. The adsorption isotherm followed the Langmuir model, implying monolayer adsorption process. The maximum adsorption capacity (qm) for Cu(II) determined by the Langmuir model was 103.9 mg/g. The adsorption thermodynamics showed an endothermic and spontaneous adsorption. FTIR and XPS studies suggested coordination or chelation as the possible adsorption mechanism. Lewatit MDS TP 220 exhibited excellent Cu(II) adsorption, desorption with 2 M ammonium hydroxide (NH4OH), and selectivity in multi-metal ions solution. Additionally, the resin demonstrated excellent reusability after five regeneration steps. This chelating resin is a potential adsorbent for effective and recurrent recovery of Cu(II) from copper tailings and wastewater, thereby contributing to environmental remediation.

Characterization and In vitro Dissolution Assessment of Pitavastatin-polyvinyl Pyrrolidone and Kollicoat®IR Solid Dispersions Prepared by Solvent Evaporation and Fusion Methodologies

Pitavastatin (PTV) is a potent lipid lowering drug that acts on hepatocytes by blocking the 3-hydroxy-3- methylglutaryl-CoA reductase enzyme. As a Biopharmaceutical Classification System (BCS) Class II drug, PTV possesses very low water solubility; hence, poor bioavailability leads to poor drug delivery to the target organ. The study aims to develop various PTV solid dispersion (SD) formulations and to investigate the release profile of PTV SD systems. Different PTV physical mixing and SD formulations were prepared using polyvinylpyrrolidone (Kollidon®90F) and Kollicoat®IR hydrophilic polymers by fusion and solvent evaporation approaches. The efficacy of the formulations was evaluated by in vitro PTV release studies. Subsequently, the characterization of SD formulations was performed using thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). The in vitro release studies confirmed that all the developed formulations showed a comparatively better release percentage (75.31–98.45%) than the pure PTV (61.76%) after 60 min. Additionally, the outcomes showed that raising the concentration of both polymers improved PTV's ability to dissolve. In comparison to physical mixing formulations, SD formulations made using fusion and solvent evaporation processes performed better during dissolution. The TGA, DSC, and FTIR studies confirmed that the tested SD formulations (1:2, 1:3 ratios) were stable at high temperatures with a reduction in crystallinity and no notable interaction between the drug and polymers. The SEM analysis showed that the PTV was evenly spread out in the carriers and that the crystal-like structure of the PTV had changed into an amorphous form. Bangladesh Pharmaceutical Journal 27(1): 37-50, 2024 (January)

Exploring the multiferroic and water sensing behavior of Cu/Er co-substituted ferrites as key enablers for next-gen hydroelectric cells

Currently, the consumption of energy has enormously risen which in turn causes environmental degradation and this associated degraded environment prompts the research around the devices that produce green energy. Here, we have reported a cost-effective way to produce copper and erbium co-substituted cobalt ferrite nanoparticles [Co1-xCuxFe1.85Er0.15O4, 0.00 ≤ x ≤ 0.09] via sol-gel auto combustion synthesis route. The structural analysis from X-ray diffraction (XRD) measurements confirms the cubic structure of nanoparticles with an average crystallite size of 22 nm. The FT-IR (Fourier transform infrared spectroscopy) studies have revealed the expansion in the octahedral (431-434.85 cm−1) and tetrahedral bands (523-538.82 cm−1) with the increase in the copper content. FESEM-EDX (Field emission scanning electron microscopy) morphology unveils the porous nanostructures with an average particle size around 82.38 nm using ImageJ software. Electrical studies display a net increment in the dielectric constant (ε´) value from 66.908 to 147.97 with an increase in copper concentration from 0 % to 9 % because of the agglomeration of copper and erbium ions at the grain boundaries. It has been also noted that the addition of Cu2+ ions above 6 % into erbium-substituted cobalt ferrite caused a tremendous decrease in the Ms value from 93.75 emu/g to 57.25 emu/g due to weak superexchange interaction upon the co-substitution of copper and erbium ions in cobalt ferrites. The overall value of saturation polarization (Ps) has been improved from 1.009 μC/cm2 to 12.79 μC/cm2 upon increasing the copper concentration in the spinel ferrite. The improvement in ferroelectricity and ferromagnetism in co-substituted cobalt ferrite confirms the presence of multiferroicity in them. The I–V measurements yield prepared hydroelectric cells can deliver a maximum current of 14.772 mA with a power of 11.300 mW for 9 % copper doping in the erbium substituted spinel ferrite while the lowest is reported around 4.08 mA and power of 3.18 mW for only erbium substituted cobalt ferrite. Therefore, the prepared material can be suggested for its useful application in hydroelectric cells.

Preparation, Characterization and In-vitro Evaluation of Nano Encapsulated 1-Octacosanol for Solubility Enhancing by using Various Polymers through Spray Drying Approach

This research aimed to develop a nano-encapsulated free-flow powder of 1-octacosanol for functional food application. We had prepared stable green nano-emulsion oil in water by Dyno Mill and spray dryer for free flow powder by using different polymers (Hydroxypropyl methylcellulose, polyvinylpyrrolidone, octenyl succinate starches) as hydrophilic polymers in different ratios for enhancing the solubility. Zeta potential, X-ray diffraction (XRD), fourier transform infrared spectroscopy (FTIR), encapsulation efficiency, particle size distribution, surface morphology, differential scanning calorimetry spectroscopy and in-vitro dissolution research were used to analyze 1-octacosanol. The optimized nano-emulsion preparation F15 consists of an average particle size 720.9 nm, zeta potential -24.5 mV shows stable nano-emulsion oil in water type, and encapsulation efficiency was found to be 96.76%, FTIR studies did not show any evidence of interaction between the herbal extract and the polymers. XRD shows the conversion of crystalline to amorphous nature of powder. In differential scanning calorimetry (DSC), spectroscopy studies found three major peaks in standard herbal extract peaks is 60.21, 67.16, 81.27°C and nano-encapsulated spray dried powder peaks are 58.18, 66.44, 79.25°C with minor moisture absorbed by the polymer in formulation. This evaluation shows significant improvement between normal herbal extract of 1-octacosanol and encapsulated spray-dried powder of 1-octacosanol for functional food application successfully improving the water solubility without changing a structural and chemical properties of the 1-octacosanol crystal.