Bioactivities of holmium(III) and gadolinium(III) complexes of thymoquinone

Chemotherapeutic agents which are the main stay in cancer treatment are toxic with numerous contrary side effects. A number of chemical, physical, and computational techniques were applied to synthesize and elucidate the structural and functional characterization of the new designed bioligands and their metal complexes. Besides, several biological techniques for developing therapeutics and diagnostics agents of these new designed materials were used. The trivalent holmium(III) and gadolinium(III) metal complexes of thymoquinone (TQ) were synthesized. Toxicities and other bioactivites were undertaken with existing drug combinations and more effective tumor models will be established. The molecular structures of TQ-metal complexes were elucidated based on particular spectral approaches. The NF-kB (nuclear factor kappa-light-chain enhancer of activated B Cells) luciferase, elastase release, superoxide anion (O2•−) generation, and DPPH (1,1-diphenyl-2-picryl hydrazyl) free-radical scavenging activities of TQ and its synthesized complexes were elucidated and discussed. The core research is to use coordination and organometallic chemistry to design new bioligands and binary, ternary, mixed ligand, multi metal multi ligand complexes pursing a bio target continuously with structure-activity relationships (SARS).                     KEY WORDS: Thymoquinone, Holmium, Gadolinium, Bioactivities   Bull. Chem. Soc. Ethiop. 2021, 35(1), 87-96. DOI: https://dx.doi.org/10.4314/bcse.v35i1.

Study of generalized Lemaître–Tolman–Bondi spacetime in Palatini

The objective of this paper is to investigate the continuation of Lemaître–Tolman–Bondi (LTB) space-time for dissipative dust configuration in the direction of Palatini f(R) theory. In this context, the generalized form of field and dynamical equations will be formulated. We explore the effects of kinematical variables and curvature invariant on our proposed fluid configuration. The significance of Palatini f(R) scalar variables computing through the orthogonal splitting of Riemann-tensor for dissipative dust spheres will be reported. Furthermore, two subcases of LTB space-time have been carried out to note down its symmetric aspects. It is revealed that extended LTB space-time has characteristics comparable to that of LTB and computed scalar variables in both situations have identical dependance on source profile even under the effects of Palatini technique

Thermal analysis of radiated (aluminum oxide)/water through a magnet based geometry subject to Cattaneo-Christov and Corcione’s Models

The study of heat transfer problems is of paramount significance due to their wider spectrum of applications specifically in heat engines, insulation, chemical and thermal engineering etc. The formulation of new model completed via enhanced nanofluid properties and under physical parameters and then in-depth mathematical investigation done via numerical approach and scrutinized the results for preeminent physical parameters. Thermal conductivity estimation under Corcione’s model increased by taking the particles concentration up to φ=0.6% and electrical conductivity diminishes from 0.999001 to 0.994036. Further, the eye bird analysis of the results revealed that the stretching number S1 from 0.1 to 1.3 and α2=0.1,0.2,0.3,0.4 resists the fluid flow over the surface and the nanofluid movement is slow compared to conventional liquid due to high viscous forces. Keeping the concentration φ% and Ha=0.1,0.2,0.3,0.4 the velocity G'(η) drops and it rises for increasing S1. Furthermore, the addition of radiative thermal flux (Rd) and internal heating effects (Hg) in the model increase its applicability for high thermal transport applications and is observed maximum for nanofluid. The local thermal rate at the surface could be enhanced by keeping Rd and Hg from 0.0 to 0.8 and minimal rate of heat transport is observed for simple fluid while it is dominant for nanofluid

Investigation of blood flow characteristics saturated by graphene/CuO hybrid nanoparticles under quadratic radiation using VIM: study for expanding/contracting channel

Abstract The importance of heat transfer in nanoliquids cannot avoided because it playing crucial role in the applied research fields. The potential area of applications included but restricted to applied thermal, biomedical, mechanical and chemical engineering. Therefore, it is the need of time to introduce new efficient way to enhance the heat transport rate in common fluids. The major aim of this research is to develop a new heat transport BHNF (Biohybrid Nanofluid Model) model in a channel having expanding/contracting walls up to Newtonian regimes of blood. The two sort of nanomaterials (Graphene + CuO) along with blood as base solvent are taken for the formation of working fluid. After that, the model analyzed via VIM (Variational Iteration Method) to examine the influence of involved physical parameters on the behavior of bionanofluids. The model results revealed that the bionanofluids velocity rises towards the lower and upper channel end when the expanding/contracting of the walls in the range of 0.1–1.6 (expanding case) and $$- \, 0.1$$ - 0.1 to $$1.6$$ 1.6 (contraction case). The working fluid attained high velocity in the neighboring of center portion of the channel. By increasing the walls permeability ( $${A}_{1}=\text{0.1,0.2,0.3,0.4}$$ A 1 = 0.1,0.2,0.3,0.4 ), the fluid movement can be reduced and optimum decrement observed about $$\eta =0.0$$ η = 0.0 . Further, inclusion of thermal radiation (Rd) and temperature coefficient ( $${\theta }_{r}$$ θ r ) observed good to enhance thermal mechanism in both hybrid and simple bionanofluids. The present ranges of Rd and $${\theta }_{r}$$ θ r considered from $$0.1$$ 0.1 to $$0.9$$ 0.9 and $$0.1$$ 0.1 to $$1.4$$ 1.4 , respectively. Thermal boundary layer reduced in the case of simple bionanoliquid keeping $${P}_{r}=21.0$$ P r = 21.0

Investigation of improved heat transport featuring in dissipative ternary nanofluid over a stretched wavy cylinder under thermal slip

Purpose: and Methodology: The heat transport investigation in non-Newtonian fluids suspended by distinct sort of nanoparticles is a rich motive in the present time. Therefore, inspired by the physical characteristics of base fluid and ternary nanoparticles (Al2O3-CuO-Cu), a comprehensive analysis conducted over a cylinder with wavy radius with special emphasis in Saddle and Nodal points. The key effects of dissipation, the first order thermal slip, surface convection and stretching/shrinking added in the model. The acquired model is then examined via RK-scheme and portrayed the results against the physical ranges of the parameters. Key findings: A comprehensive discussion of the results provided that the nanofluid velocity increased for higher Casson number (α=0.5,1.0,1.5,2.0) and is examined optimum for stretched cylinder surface. The higher viscous dissipation which results the effects of Eckert number (Ec=0.01,0.02,0.03,0.04), surface convection due to Biot number (B1=0.1,0.2,0.3,0.4) and the first order thermal slip (α1=0.1,0.3,0.5,0.7) are the key physical factors to acquire the favorable heat transfer amount for the practical interest. Further, the particles concentration in the range of 1%–6% is observed good to increase the heat transmission in ternary nanoliquid and the values of effective characteristics (dynamics viscosity and thermal conductivity) upsurges against the concentration factor up to 6%

Gum Arabic-Magnetite Nanocomposite as an Eco-Friendly Adsorbent for Removal of Lead(II) Ions from Aqueous Solutions: Equilibrium, Kinetic and Thermodynamic Studies

In this study, a gum Arabic-magnetite nanocomposite (GA/MNPs) was synthesized using the solution method. The prepared nanocomposite was characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), vibrating sample magnetometer (VSM), and thermogravimetric analysis (TGA). The prepared composite was evaluated for the adsorption of lead(II) ions from aqueous solutions. The controlling factors such as pH, contact time, adsorbent dose, initial ion concentration, and temperature were investigated. The optimum adsorption conditions were found to be 0.3 g/50 mL, pH = 6.00, and contact time of 30 min. The experimental data well fitted the pseudo-second-order kinetic model and the Langmuir isotherm model. The maximum adsorption capacity was determined as 50.5 mg/g. Thermodynamic parameters were calculated postulating an endothermic and spontaneous process and a physio-sorption pathway

MXene (Ti₃C₂T_x)-Embedded Nanocomposite Hydrogels for Biomedical Applications: A Review

Polymeric nanocomposites have been outstanding functional materials and have garnered immense attention as sustainable materials to address multi-disciplinary problems. MXenes have emerged as a newer class of 2D materials that produce metallic conductivity upon interaction with hydrophilic species, and their delamination affords monolayer nanoplatelets of a thickness of about one nm and a side size in the micrometer range. Delaminated MXene has a high aspect ratio, making it an alluring nanofiller for multifunctional polymer nanocomposites. Herein, we have classified and discussed the structure, properties and application of major polysaccharide-based electroactive hydrogels (hyaluronic acid (HA), alginate sodium (SA), chitosan (CS) and cellulose) in biomedical applications, starting with the brief historical account of MXene’s development followed by successive discussions on the synthesis methods, structures and properties of nanocomposites encompassing polysaccharides and MXenes, including their biomedical applications, cytotoxicity and biocompatibility aspects. Finally, the MXenes and their utility in the biomedical arena is deliberated with an eye on potential opportunities and challenges anticipated for them in the future, thus promoting their multifaceted applications

Platinum and vanadate Bioactive Complexes of Glycoside Naringin and Phenolates

Platinum(II) and vanadium(V) solid binary and ternary complexes involving naringin, a flavanone glycoside in found in grapefruit, and some phenolic acids were synthesized and fully characterized using detailed structural and spectroscopic analysis techniques such as IR, NMR, and SEM techniques. The magnetic susceptibility results as well line drawings of the platinum and vanadium complexes showed four-coordinate square-planar and remarkable low-spin diamagnetic species; which is in agreement with the structures proposed. The cytotoxic activities of the binary and ternary vanadium and platinum metal complexes of phenolic acids and naringin were tested and evaluated against HepG2 (human hepatocellular carcinoma), MCF-7 (human breast adenocarcinoma), and HCT116 (human colorectal carcinoma) tumor cell lines. Also, their antioxidant activities were examined by free radical scavenging assay. The relationship between the chemical structure of the synthesized complexes and their biological influence was studied and evaluated