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Materials (Basel, Switzerland) Jun 2024Hybrid organic-inorganic lead halide perovskites (LHPs) have emerged as a highly significant class of materials due to their tunable and adaptable properties, which make...
Hybrid organic-inorganic lead halide perovskites (LHPs) have emerged as a highly significant class of materials due to their tunable and adaptable properties, which make them suitable for a wide range of applications. One of the strategies for tuning and optimizing LHP-based devices is the substitution of cations and/or anions in LHPs. The impact of Cs substitution at the A site on the structural, vibrational, and elastic properties of MACsPbCl-mixed single crystals was investigated using X-ray diffraction (XRD) and Raman and Brillouin light scattering techniques. The XRD results confirmed the successful synthesis of impurity-free single crystals, which exhibited a phase coexistence of dominant cubic and minor orthorhombic symmetries. Raman spectroscopy was used to analyze the vibrational modes associated with the PbCl octahedra and the A-site cation movements, thereby revealing the influence of cesium incorporation on the lattice dynamics. Brillouin spectroscopy was employed to investigate the changes in elastic properties resulting from the Cs substitution. The incorporation of Cs cations induced lattice distortions within the inorganic framework, disrupting the hydrogen bonding between the MA cations and PbCl octahedra, which in turn affected the elastic constants and the sound velocities. The substitution of the MA cations with smaller Cs cations resulted in a stiffer lattice structure, with the two elastic constants increasing up to a Cs content of 30%. The current findings facilitate a fundamental understanding of mixed lead chloride perovskite materials, providing valuable insights into their structural and vibrational properties.
PubMed: 38930231
DOI: 10.3390/ma17122862 -
Foods (Basel, Switzerland) May 2024Bixin is the main carotenoid found in the outer portion of the seeds of L., commercially known as annatto. This compound is industrially employed in pharmaceutical,...
Bixin is the main carotenoid found in the outer portion of the seeds of L., commercially known as annatto. This compound is industrially employed in pharmaceutical, cosmetic, and food formulations as a natural dye to replace chemical additives. This study aimed to extract bixin from annatto seeds and obtain encapsulated bixin in a powder form, using freeze-drying encapsulation and maltodextrin as encapsulating agent. Bixin was extracted from annatto seeds employing successive washing with organic solvents, specifically hexane and methanol (1:1 /), followed by ethyl acetate and dichloromethane for subsequent washes, to effectively remove impurities and enhance bixin purity, and subsequent purification by crystallization, reaching 1.5 ± 0.2% yield (or approximately 15 mg of bixin per gram of seeds). Bixin was analyzed spectrophotometrically in different organic solvents (ethanol, isopropyl alcohol, dimethylsulfoxide, chloroform, hexane), and the solvents chosen were chloroform (used to solubilize bixin during microencapsulation) and hexane (used for spectrophotometric determination of bixin). Bixin was encapsulated according to a 2 experimental design to investigate the influence of the concentration of maltodextrin (20 to 40%) and bixin-to-matrix ratio (1:20 to 1:40) on the encapsulation efficiency (EE%) and solubility of the encapsulated powder. Higher encapsulation efficiency was obtained at a maltodextrin concentration of 40% / and a bixin/maltodextrin ratio of 1:20, while higher solubility was observed at a maltodextrin concentration of 20% / for the same bixin/maltodextrin ratio. The encapsulation of this carotenoid by means of freeze-drying is thus recognized as an innovative and promising approach to improve its stability for further processing in pharmaceutical and food applications.
PubMed: 38890850
DOI: 10.3390/foods13111622 -
Chemistry of Materials : a Publication... Jun 2024The effects of impurities on reaction precursors for metal-organic framework (MOF) synthesis have not been studied in extensive detail. The impact of these impurities...
The effects of impurities on reaction precursors for metal-organic framework (MOF) synthesis have not been studied in extensive detail. The impact of these impurities can be an important factor while considering scale-up of these materials. In this work, we study the apparently positive impact of the presence of manganese ions for the synthesis of a Co-based MOF, Massey University Framework-16 (MUF-16). The presence of a trace amount of manganese in the reaction mixture led to consistently high CO uptake across multiple batches. Characterization including X-ray diffraction, scanning electron microscopy, Fourier transform infrared-attenuated total reflectance, ultraviolet-visible spectroscopy, thermogravimetric analysis, X-ray photoelectron spectroscopy, and extended X-ray absorption fine structure spectroscopy led us to hypothesize that the differences in CO adsorption among materials with differing synthesis routes arise from variations in the local environment around the cobalt metal center. Aided by density functional theory calculations, we speculate that manganese ions get inserted into the structure during crystallization and act as catalysts for ligand substitution, improving the possibility for octahedral coordination of cobalt with the ligand, thus leading to Co-based pristine structures with higher CO uptakes.
PubMed: 38883436
DOI: 10.1021/acs.chemmater.4c00137 -
Journal of Pharmaceutical and... Jun 2024Omeprazole (OME) is a proton pump inhibitor used to treat gastroesophageal reflux disease associated conditions. The current study presents an Analytical Quality by...
Omeprazole (OME) is a proton pump inhibitor used to treat gastroesophageal reflux disease associated conditions. The current study presents an Analytical Quality by Design-based approach for the development of a CE method for OME impurity profiling. The scouting experiments suggested the selection of solvent modified Micellar ElectroKinetic Chromatography operative mode using a pseudostationary phase composed of sodium dodecyl sulfate (SDS) micelles and n-butanol as organic modifier in borate buffer. A symmetric three-level screening matrix 3//16 was used to evaluate the effect of Critical Method Parameters, including Background Electrolyte composition and instrumental settings, on Critical Method Attributes (critical resolution values, OME peak width and analysis time). The analytical procedure was optimized using Response Surface Methodology through a Central Composite Orthogonal Design. Risk of failure maps made it possible to define the Method Operable Design Region, within which the following optimized conditions were selected: 72 mM borate buffer pH 10.0, 96 mM SDS, 1.45 %v/v n-butanol, capillary temperature 21 °C, applied voltage 25 kV. The method was validated according to ICH guidelines and robustness was evaluated using a Plackett-Burman design. The developed procedure enables the simultaneous determination of OME and seven related impurities, and has been successfully applied to the analysis of pharmaceutical formulations.
PubMed: 38879949
DOI: 10.1016/j.jpba.2024.116295 -
Scientific Reports Jun 2024A series of 4-ferrcenylbutyl carboxylate esters with different alkyl chain length (C-C) of carboxylic acids were synthesized using FeO@SiO@(CH)-Im-bisEthylFc[I]...
A series of 4-ferrcenylbutyl carboxylate esters with different alkyl chain length (C-C) of carboxylic acids were synthesized using FeO@SiO@(CH)-Im-bisEthylFc[I] nanoparticles as catalyst and have been characterized with FT-IR, H NMR, and C NMR. Ferrocenyl-based esters were used as corrosion inhibitors of mild steel in the 1M HCl solution as corrosive media. The corrosion inhibition efficiency of the synthesized ferrocenyl-based esters has been assessed by electrochemical impedance spectroscopy (EIS), potentiodynamic polarization (PDP), atomic force microscopy (AFM), and scanning electron microscopy (SEM). The 4-ferrocenylbutyl propionate showed a more effective corrosion inhibition behavior among the studied esters with 96% efficiency after immersion in the corrosive media for 2 weeks. The corrosion inhibition mechanism is dominated by formation of passive layer of inhibitor on the surface of the mild steel by adsorption. Moreover, the adsorption characteristics of 4-butylferrcenyl carboxylate esters on mild steel were thoroughly explored using density functional theory calculations. It was found that the Fe atoms located around the C impurity in the mild steel are the most efficient and active sites to adsorb 4-butylferrcenyl carboxylate esters.
PubMed: 38879584
DOI: 10.1038/s41598-024-64471-0 -
Journal of Hazardous Materials Aug 2024We present a new method for investigating the oxidation and emission behavior of air-permeable materials. Employing this method, a differentiated statement can be made...
We present a new method for investigating the oxidation and emission behavior of air-permeable materials. Employing this method, a differentiated statement can be made about the extent to which critical volatile organic compounds (VOCs) such as formaldehyde, acetaldehyde, and acrolein are contained in the material as impurities or formed by thermo-oxidative degradation of the polymer matrix in the use phase. The parameters affecting methods of VOC analysis are reviewed and considered for the developed method. The molecular mechanisms of VOC formation are discussed. Toxicological implications of the reaction kinetics are put into context with international guidelines and threshold levels. This new method enables manufacturers of cellular materials not only to determine the oxidative stability of their products but also to optimize them specifically for higher durability. ENVIRONMENTAL IMPLICATION: Cellular materials are ubiquitous in the technosphere. They play a crucial role in various microenvironments such as automotive interiors, building insulation, and cushioning. These materials are susceptible to oxidative breakdown, leading to the release of formaldehyde, acetaldehyde, and acrolein. The ecotoxicological profiles of these compounds necessitate monitoring and regulation. The absence of reproducible and reliable analytical methods restricts research and development aimed at risk assessment and mitigation. This work significantly enhances the toolbox for optimizing the oxidative stability of any open-cell cellular material and evaluating these materials in terms of their temperature-dependent oxidation and emission behavior.
PubMed: 38843638
DOI: 10.1016/j.jhazmat.2024.134747 -
Heliyon May 2024Greenly synthesized nanoparticles have garnered attention due to their low environmental footprint, but impurities limit their applications. A novel semi-organic method...
Greenly synthesized nanoparticles have garnered attention due to their low environmental footprint, but impurities limit their applications. A novel semi-organic method for synthesizing silver nanoparticles (AgNPs) using bio-based chelating fuels ( subsp.) reduces the undesirable impurities. The study also showcases the impact of bio-based chelating fuel on various characteristics of AgNPs in comparison to synthetic chelating fuel. The antimicrobial efficacy of the synthesized AgNPs in conjunction with honey was also assessed against The XRD analysis showed cubic structure of AgNPs. The FESEM and TEM analysis showed that the well-connected spherical-shaped AgNPs (∼3-120 nm diameter) while EDS confirmed the presence of Ag in all samples. The TEM analysis also revealed layers of carbonates in AgNPs synthesized using bio-based chelating fuels. XPS investigation confirmed the absence of any prominent impurities in prepared samples and AgNPs have not experienced oxidation on their surface. However, notable surface charging effects due to the uneven conductivity of the particles were observed. The broth dilution method showed that all mixtures containing AgNPs in combination with honey exhibited a significant bacterial growth reduction over a period of 120 h. The highest growth reduction of ∼75 % is obtained for the mixture having AgNPs () while the least growth reduction of ∼51 % is obtained for the mixture having AgNPs (Beta vulgaris subsp.). The findings affirm that AgNPs can be successfully synthesized using bio-based chelating fuels with negligible ecological consequences and devoid of contaminants. Moreover, the synthesized AgNPs can be employed in conjunction with honey for antibacterial purposes.
PubMed: 38818153
DOI: 10.1016/j.heliyon.2024.e31424 -
ACS Applied Nano Materials May 2024Nanoscale hybrid inorganic-organic multilayers are attractive for accessing emergent phenomena and properties through superposition of nanomolecularly-induced interface...
Nanoscale hybrid inorganic-organic multilayers are attractive for accessing emergent phenomena and properties through superposition of nanomolecularly-induced interface effects for diverse applications. Here, we demonstrate the effects of interfacial molecular nanolayers (MNLs) of organo-diphosphonates on the growth and stability of titania nanolayers during the synthesis of titania/MNL multilayers by sequential atomic layer deposition and single-cycle molecular layer deposition. Interfacial organo-diphosphonate MNLs result in ∼20-40% slower growth of amorphous titania nanolayers and inhibit anatase nanocrystal formation from them when compared to amorphous titania grown without MNLs. Both these effects are more pronounced in multilayers with aliphatic backbone-MNLs and likely related to impurity incorporation and incomplete reduction of the titania precursor indicated by our spectroscopic analyses. In contrast, both MNLs result in two-fold higher titania nanolayer roughness, suggesting that roughening is primarily due to MNL bonding chemistry. Such MNL-induced effects on inorganic nanolayer growth rate, roughening, and stability are germane to realizing high-interface-fraction hybrid nanolaminate multilayers.
PubMed: 38808308
DOI: 10.1021/acsanm.4c00743 -
International Journal of Pharmaceutics May 2024This research shows the detailed comparison of Raman and near-infrared (NIR) spectroscopy as Process Analytical Technology tools for the real-time monitoring of a...
This research shows the detailed comparison of Raman and near-infrared (NIR) spectroscopy as Process Analytical Technology tools for the real-time monitoring of a protein purification process. A comprehensive investigation of the application and model development of Raman and NIR spectroscopy was carried out for the real-time monitoring of a process-related impurity, imidazole, during the tangential flow filtration of Receptor-Binding Domain (RBD) of the SARS-CoV-2 Spike protein. The fast development of Raman and NIR spectroscopy-based calibration models was achieved using offline calibration data, resulting in low calibration and cross-validation errors. Raman model had an RMSEC of 1.53 mM, and an RMSECV of 1.78 mM, and the NIR model had an RMSEC of 1.87 mM and an RMSECV of 2.97 mM. Furthermore, Raman models had good robustness when applied in an inline measurement system, but on the contrary NIR spectroscopy was sensitive to the changes in the measurement environment. By utilizing the developed models, inline Raman and NIR spectroscopy were successfully applied for the real-time monitoring of a process-related impurity during the membrane filtration of a recombinant protein. The results enhance the importance of implementing real-time monitoring approaches for the broader field of diagnostic and therapeutic protein purification and underscore its potential to revolutionize the rapid development of biological products.
PubMed: 38797253
DOI: 10.1016/j.ijpharm.2024.124251 -
Nanomaterials (Basel, Switzerland) May 2024In this paper, we designed and investigated a reduction-based method to synthesize controllably monodisperse superparamagnetic nano FeO colloidal clusters for...
In this paper, we designed and investigated a reduction-based method to synthesize controllably monodisperse superparamagnetic nano FeO colloidal clusters for magnetically responsive photonic crystals. It was shown that the addition of ascorbic acid (VC) to the system could synthesize monodisperse superparamagnetic nano FeO and avoided the generation of γ-FeO impurities, while the particle size and saturation magnetization intensity of nano FeO gradually decreased with the increase of VC dosage. Nano FeO could be rapidly assembled into photonic crystal dot matrix structures under a magnetic field, demonstrating tunability to various diffraction wavelengths. The nano FeO modified by polyvinylpyrrolidone (PVP) and silicon coated could be stably dispersed in a variety of organic solvents and thus diffracted different wavelengths under a magnetic field. This is expected to be applied in various scenarios in the field of optical color development.
PubMed: 38786808
DOI: 10.3390/nano14100852