Formulation of Quaternized Aminated Chitosan Nanoparticles for Efficient Encapsulation and Slow Release of Curcumin

An effective drug nanocarrier was developed on the basis of a quaternized aminated chitosan (Q-AmCs) derivative for the efficient encapsulation and slow release of the curcumin (Cur)-drug. A simple ionic gelation method was conducted to formulate Q-AmCs nanoparticles (NPs), using different ratios of sodium tripolyphosphate (TPP) as an ionic crosslinker. Various characterization tools were employed to investigate the structure, surface morphology, and thermal properties of the formulated nanoparticles. The formulated Q-AmCs NPs displayed a smaller particle size of 162 ± 9.10 nm, and higher surface positive charges, with a maximum potential of +48.3 mV, compared to native aminated chitosan (AmCs) NPs (231 ± 7.14 nm, +32.8 mV). The Cur-drug encapsulation efficiency was greatly improved and reached a maximum value of 94.4 ± 0.91%, compared to 75.0 ± 1.13% for AmCs NPs. Moreover, the in vitro Cur-release profile was investigated under the conditions of simulated gastric fluid [SGF; pH 1.2] and simulated colon fluid [SCF; pH 7.4]. For Q-AmCs NPs, the Cur-release rate was meaningfully decreased, and recorded a cumulative release value of 54.0% at pH 7.4, compared to 73.0% for AmCs NPs. The formulated nanoparticles exhibited acceptable biocompatibility and biodegradability. These findings emphasize that Q-AmCs NPs have an outstanding potential for the delivery and slow release of anticancer drugs.     

A variant of Hardy's and Miyachi's theorems for the Bessel–Struve transform

In this paper, we establish new versions of Hardy's and Miyachi's theorems for the Bessel–Struve transform.     

Synthesis and characterization of some novel 1,3-diaryl pyrazole bearing 2-oxopyridine-3,5-dicarbonitrile derivatives

Russian Journal of General Chemistry - A series of new 1-{[1-(3-chlorophenyl)-3-(4-methoxyphenyl)-1H-pyrazol-4-yl]methyleneamino}-6-amino-1,2-dihydro-4-(substitutedphenyl)-2-oxopyridine-3,5-di...     

Krull Dimension in Power Series Ring Over an Almost Pseudo-Valuation Domain

Let R be an integral domain. We say that R is a star-domain if R has at least a height one prime ideal and if for each height one prime ideal P of R, R satisfies the acc on P-principal ideals (i.e., ideals of the form aP, a ∈ R). We prove that if R is an APVD with nonzero finite Krull dimension, then the power series ring R[[X]] has finite Krull dimension if and only if R is a residually star-domain (i.e., for each nonmaximal prime ideal P of R, R/P is a star-domain) if and only if R[[X]] is catenarian.     

Synthesis and antioxidant activity of some thiazolidin-4-one derivatives

Abstract  4-Fluorobenzaldehyde was used for the preparation of 2-(4-fluorophenyl)thiazolidin-4-one derivatives which were allowed to react with chloroacetonitrile and acrylonitrile to produce 3-(2-(4-fluorophenyl)-4-oxothiazolidine3-yl)acetonitrile and 3-(2-(4-fluorophenyl)-4-oxothiazoledine-3-yl)propanenitrile. Biological evaluation of some of the compounds showed that many had promising antioxidant activity. Graphical Abstract        

New Pyridopyrimidone Derivatives: Synthesis,Molecular Docking Studies,and Potential Anticancer Activity

Russian Journal of General Chemistry - A new series of pyrido[2,3-d]pyrimidones incorporated pyrazoles and fused triazoles are synthesized and tested in vitro for cytotoxic effect against cancer...     

Morphology and optical properties of p-type porous GaAs(1 0 0) layers made by electrochemical etching

Porous GaAs layers were formed by electrochemical etching of p-type GaAs(1 0 0) substrates in HF solution. A surface characterization has been performed on p-type GaAs samples using X-ray photoelectron spectroscopy (XPS) technique in order to get information about the chemical composition, particularly on the surface contamination. According to the XPS spectra, the oxide layer on as-received porous GaAs substrates contains As₂O₃, As₂O₅ and Ga₂O₃. Large amount of oxygen is present at the surface before the surface cleaning.Compared to untreated GaAs surface, room temperature photoluminescence (PL) investigations of the porous layers reveal the presence of two PL bands: a PL peak at ∼871 nm and a “visible” PL peak at ∼650-680 nm. Both peak wavelengths and intensities varied from sample to sample depending on the treatment that the samples have undergone. The short PL wavelength at 650-680 nm of the porous layers is attributed to quantum confinement effects in GaAs nano-crystallites. The surface morphology of porous GaAs has been studied using atomic force microscopy (AFM). Nano-sized crystallites were observed on the porous GaAs surface. An estimation of the mean size of the GaAs nano-crystals obtained from effective mass theory and based on PL data was close to the lowest value obtained from the AFM results.     

Studies on Brilliant Green and Solochrome Red B: I. The acid-base properties

The acid-base properties of Brilliant Green and Solochrome Red B have been studied in an attempt to apply them as metallochromic or chromophoric indicators. The thermodynamic pK values 4.93 and 2.62 corresponding to the ionization of the hydrogen sulfate group and to the protonation of the second diethylamino group in Brilliant Green, and 3.46, 5.80, 7.22, and 13.30 corresponding to the ionization of the two sulfonic, the carboxylic, and the phenolic groups in Solochrome Red B, respectively, were computed from results of potentiometric and spectrophotometric measurements.     

The viscosity of normal butane,isobutane and their mixtures

The paper reports measurements of the viscosity of normal butane and isobutane at atmospheric pressure in the temperature range 25–195°C. In addition, the viscosity of mixtures of the two gases has been determined in the more limited temperature range 25–100°C. The absolute accuracy of the viscosity data is estimated as ±0.2%, whereas the ratio of the viscosity of the two pure components is determined with an uncertainty of ±0.1%. The viscosity data allow the evaluation of the diffusion coefficients for the n-butane-i-butane system.The experimental data demonstrate that there are discernible differences between the intermolecular potentials for the pair-interactions n-C₆H₁₀-n-C₄H₁₀; and i-C₄H₁₀-i-C₄H₁₀. All of the experimental data can be correlated within their experimental uncertainty with the aid of the extended law of corresponding states developed by Kestin, Ro and Wakeham. The optimum values of the two scaling parameters, σ_ij and ?_ij, for each interaction which secure this agreement are determined.