The Influence of Temperature on the Formation of Cubic Structured CdO nanoparticles and their Thin Films from bis(2-hydroxy-1-naphthaldehydato)cadmium(II) complex via Thermal Decomposition Technique

Recently, researchers have developed a great interest in the synthesis of metal oxide nanoparticles due to their potential applications in various fields of science and industry, especially in catalysis, due to their high activity. Bis(2-hydroxy-1-naphthaldehydato)cadmium(II) complexes were prepared and used as precursors for the synthesis of cadmium oxide nanoparticles via thermal decomposition method using HDA as a stabilizing agent. The prepared complexes were also used as single source precursors to prepare CdO thin films onto the glass substrates by spin coating and were annealed at 250, 300, and 350°C, respectively. The precursors were characterized by Fourier transform infrared (FTIR) spectroscopy, elemental analysis, nuclear magnetic resonance (NMR), and thermogravimetric analysis (TGA). The synthesized CdO nanoparticles and CdO thin films were characterized by ultraviolet-visible (UV-vis) spectroscopy, photoluminescence (PL), X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and atomic force microscopy (AFM)

The Influence of Temperature on the Formation of Cubic Structured CdO nanoparticles and their Thin Films from bis(2-hydroxy-1-naphthaldehydato)cadmium(II) complex via Thermal Decomposition Technique

Recently, researchers have developed a great interest in the synthesis of metal oxide nanoparticles due to their potential applications in various fields of science and industry, especially in catalysis, due to their high activity. Bis(2-hydroxy-1-naphthaldehydato)cadmium(II) complexes were prepared and used as precursors for the synthesis of cadmium oxide nanoparticles via thermal decomposition method using HDA as a stabilizing agent. The prepared complexes were also used as single source precursors to prepare CdO thin films onto the glass substrates by spin coating and were annealed at 250, 300, and 350°C, respectively. The precursors were characterized by Fourier transform infrared (FTIR) spectroscopy, elemental analysis, nuclear magnetic resonance (NMR), and thermogravimetric analysis (TGA). The synthesized CdO nanoparticles and CdO thin films were characterized by ultraviolet-visible (UV-vis) spectroscopy, photoluminescence (PL), X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and atomic force microscopy (AFM)

ENCAPSULATION OF IBUPROFEN INTO SOLID LIPID NANOPARTICLES FOR CONTROLLED AND SUSTAINED RELEASE USING EMULSIFICATION SOLVENT EVAPORATION TECHNIQUE

Objective: The objective of the study was to encapsulate ibuprofen (IBU) into solid lipid nanoparticles (SLNs) for enhanced dissolution and achieving a sustained and controlled release of the drug from the nanocarrier. Methods: IBU loaded nanoparticles were prepared by emulsification solvent evaporation technique and characterized by Fourier Transform Infrared spectroscopy, Thermogravimetric Analysis, X-ray diffraction (XRD), and transmission electron microscopy. Release kinetics on the drug-loaded nanoparticles was carried out in phosphate buffer pH 6.8 using pharma test dissolution apparatus adopting shaking basket method at 37°C. Results: The optimized IBU-loaded SLNs had a particle size of 76.40 nm, polydispersity index of 0.275, and zeta potential of −41.3 mV. The encapsulation efficiency (EE) and DL were 99.73% and 2.31%, respectively. The Fourier transform infrared spectroscopy (FTIR) spectra confirmed successful encapsulation of the drug inside the nanocarrier as only peaks responsible for the emulsifier and the binder could be identified. This corroborated well with XRD spectra which showed a completely amorphous state of the drug-loaded nanoparticles as compared to the crystalline nature of the pure drug. The IBU-SLNs showed a release profile of up to 8 h which is a great improvement from other reported works. The drug release pattern of IBU-SLNs was best fitted with Higuchi square root model and followed the Higuchi drug release kinetics. Korsmeyer-Peppas model confirmed a non-Fickian diffusion model for the release of the drug from the matrix system. Conclusion: IBU-loaded SLNs were successfully prepared which had a sustained and controlled release. It was observed that the release of the drug from the matrix was diffusion controlled and time dependent

Optimized Loading of TiO2 Nanoparticles into Electrospun Polyacrylonitrile and Cellulose Acetate Polymer Fibers

Polyacrylonitrile (PAN), cellulose acetate (CA), PAN-TiO2, and CA-TiO2 nanofibers were prepared using the electrospinning technique under varying the loading of the TiO2 nanoparticles. The latter TiO2 nanoparticles were prepared using the sol-gel method by varying the calcination temperatures. The absorption and emission spectra illustrated the formation of TiO2 nanoparticles with an increase in absorption band edges with smaller particles. The TEM results showed the spherical morphology of the nanoparticles calcined at 500°C with an average diameter of 12.2±3.3 nm. XRD analysis revealed anatase phase as the dominant crystalline phase of the nanoparticles. TiO2 nanoparticle loadings of 0.2 and 0.4 wt% were incorporated into 16 wt% CA solutions while 1, 2, and 3 wt% of TiO2 nanoparticles were incorporated into 10 wt% PAN solutions. The SEM results illustrated the lowering in diameter and morphology of the nanofibers upon incorporation of nanoparticles. Their respective average diameters are 220, 338, 181, and 250 nm for PAN, CA, PAN-TiO2, and CA-TiO2 polymer fibers, respectively. The morphology of the nanofibers improved while the diameter increased with an increase in polymer concentration. Different loadings of TiO2 nanoparticles improved the electrospinnability and morphology and further decreased the size of the nanofibers. FTIR spectroscopy signifies the formation of nanocomposites and the presence of TiO2 nanoparticles which corresponded to the Ti-O stretching and Ti-O-Ti bands on the FTIR spectra

The influences of the concentrations of “green capping agents” as stabilizers and of ammonia as an activator in the synthesis of ZnS nanoparticles and their polymer nanocomposites

Abstract The green synthetic route for the synthesis of semiconductor nanoparticles has received special attention recently due to its features, such as low cost and environmental friendliness. The (Z)-2-(pyrrolidin-2-ylidene)thiourea was used as a ligand and allowed to react with zinc acetate to form the ZnS nanoparticles through the homogeneous precipitation method. The polyvinyl pyrrolidone and polyethylene glycol were employed as capping agents, whereas the ammonium solution was used as an activator for the stabilizers. The effects of the concentration of the capping agents on ZnS nanoparticles were investigated. The poly ethylene glycol (PEG)- or (polyvinylpyrollidone) PVP-capped zinc sulfide nanoparticles were then incorporated with polydadmac to form the polymer nanocomposites. The results from various sophisticated instruments, such as spectrophotometer (UV-Vis), photoluminescence (PL), Fourier transform infrared (FTIR), X-ray powder diffraction (XRD), transmission electron microscope (TEM), and scanning electron microscopy (SEM), reveal that the concentrations of capping agents and ammonium solution has great effects on nanomaterials.</jats:p

Dichloro (bis[diphenylthiourea]) cadmium complex as a precursor for HDA-capped CdS nanoparticles and their solubility in water

A single-source precursor route has been explored by using the diphenylthiourea cadmium complex as the source of cadmium sulphide (CdS) nanoparticles. The reaction was carried out using hexadecylamine (HDA) as the solvent and stabilising agent for the particles. The phenylthiourea complex was synthesised and characterised by means of a combination of spectroscopic techniques, microanalysis and X-ray crystal structural analysis. The diphenylthiourea complex was thermolysed in HDA at 120 °C for 1 h to produce CdS nanoparticles. The CdS nanoparticles prepared were made water-soluble via a ligand exchange reaction involving the use of pyridine to displace HDA. The pyridine was, in turn, replaced by glucose and glucuronic acid. The absorption and emission spectra showed the typical features of quantum confinement for the nanoparticles for both HDA-capped and glucose- or glucuronic acid-capped CdS nanoparticles. The change in the capping groups, from HDA to glucose and glucuronic acid, resulted in absorption and emission features that were almost similar, with only slight red-shifting and tailing

Hierarchical Nanoflowers of Colloidal WS2 and Their Potential Gas Sensing Properties for Room Temperature Detection of Ammonia

A one-step colloidal synthesis of hierarchical nanoflowers of WS2 is reported. The nanoflowers were used to fabricate a chemical sensor for the detection of ammonia vapors at room temperature. The gas sensing performance of the WS2 nanoflowers was measured using an in-house custom-made gas chamber. SEM analysis revealed that the nanoflowers were made up of petals and that the nanoflowers self-assembled to form hierarchical structures. Meanwhile, TEM showed the exposed edges of the petals that make up the nanoflower. A band gap of 1.98 eV confirmed a transition from indirect-to-direct band gap as well as a reduction in the number of layers of the WS2 nanoflowers. The formation of WS2 was confirmed by XPS and XRD with traces of the oxide phase, WO3. XPS analysis also confirmed the successful capping of the nanoflowers. The WS2 nanoflowers exhibited a good response and selectivity for ammonia

Antimicrobial Activity of Amino Acid-Capped Zinc and Copper Sulphide Nanoparticles

The synthesis of polydispersed zinc sulphide and copper sulphide nanocrystals capped with polar L-alanine (Aln) and l-aspartic acid (Asp) molecules is reported. The resulting nanocrystals were characterized by UV-visible spectroscopy (UV-Vis), photoluminescence (PL), X-ray diffraction (XRD), transmission electron microscopy (TEM), and Fourier transform infrared spectroscopy (FT-IR). UV-Vis absorption spectra of all samples were blue-shifted from the bulk band edges due to quantum confinement effects. PL emission spectrum of the nanoparticles showed peaks at 453 and 433 nm for Aln-capped ZnS and CuS nanoparticles, respectively, while peaks for Asp-capped ZnS and CuS nanoparticles were observed at 455 and 367 nm, respectively. The average particle sizes for Aln-capped ZnS and Asp-capped ZnS nanoparticles synthesized at 35°C were measured to be 2.88 nm and 1.23 nm, respectively. The antibacterial properties were tested using different strains of both positive and negative bacteria and fungi. It was found that capped-copper sulphide nanoparticles were more effective against the bacteria than capped-zinc sulphide nanoparticles. Staphylococcus aureus (ATCC 25923) was the most susceptible one with an MIC of 0.05 mg/mL for uncapped-CuS nanoparticles while Pseudomonas aeruginosa (ATCC 15442) and Cryptococcus neoformans (ATCC 14116) were the least ones with the MIC of 3.125 mg/mL for both uncapped-CuS and Aln-capped CuS