X-ray Powder Diffractometry Research Articles

Binary and ternary inclusion complexation of lapatinib ditosylate with β-cyclodextrin: preparation, evaluation and in vitro anticancer activity

BackgroundLapatinib ditosylate, an efficient tyrosine kinase inhibitor for breast cancer, poses pharmacokinetic issues, hence developing its oral delivery system is troublesome. The poor aqueous solubility of this medicament is a key impediment in developing its successful formulation. So, the current study aims to improve water solubility of Lapatinib ditosylate by using complexation technique with β-cyclodextrin and a suitable ternary agent.ResultsBinary and ternary complexes of Lapatinib ditosylate were synthesized by means of kneading and lyophilization using β-cyclodextrin and PVP K30. As a ternary agent, various hydrophilic polymers, as well as organic acids, were assessed, and PVP K30 was chosen for the final formulation based on its stability constant and complexation efficiency. When compared to pure Lapatinib ditosylate, both inclusion complexes demonstrated improved solubility, and drug dissolution. Differential scanning calorimetry (DSC), powder X-ray diffractometry (PXRD), Fourier transform infrared (FTIR), and scanning electron microscopic (SEM) techniques, all validated the complex formation. Docking studies picturized the geometry of Lapatinib ditosylate in β-cyclodextrin cavity. Using MCF-7 cell lines, investigation of anticancer activity of the pure drug and its synthesized complexes was carried out and the results revealed that the complexes had stronger anticancer activity than Lapatinib ditosylate alone.ConclusionsOverall, it can be concluded that Lapatinib ditosylate complexation increased its aqueous solubility, resulting in its increased dissolution and in vitro anticancer activity in a breast cancer cell line.

Two-Dimensional and Three-Dimensional Coordination Polymers Based on Ln(III) and 2,5-Diiodoterephthalates: Structures and Luminescent Behavior

Five new coordination polymers based on Ln3+ and 2,5-diiodoterephthalates (2,5-I-bdc)— {[La2(2,5-I-bdc)3(DMF)4]}·2DMF (1) and {[Ln2(2,5-I-bdc)3(DMF)4]} (Ln = La (2), Nd (3), Sm (4) and Eu (5))—were prepared and characterized by single crystal and powder X-ray diffractometry. Luminescent behavior was examined (the highest quantum yield is 4.5%); thermal stability was examined using thermogravimetric analysis.

Structural and morphological behaviours of l-Asparagine monohydrate at shocked conditions

Studies on the dynamic shock impact on solids also provide a magnificent scope of understating the stability of materials that are needed for high-pressure applications. Based on the impending investigations arising out of the observed experimental results of the shock-wave impact on solids, it is very much revealed that the impact of shock waves on molecular crystals is not yet well understood; especially amino acid crystals. Hence the present work deals with the assessment of crystallographic phase stability of l-Asparagine monohydrate (C4H8N2O3·H2O) amino acid powder samples against shocked-conditions and the results have been analyzed by X-ray powder diffractometry and scanning electron microscopy. The results of XRD and SEM reveal that the mother crystallographic phase of the title sample has significantly changed without inducing any crystallographic phase-transition and the observed structural modifications are discussed on the basis of previous publications reported on the static high-pressure study on the title sample.

Exploring the structural and electrochemical sensing of wide bandgap calcium phosphate/CuxFe3-xO4 core-shell nanoceramics for H2O2 detection

Calcium phosphate/Cu x- Fe 2-x O 4 core-shell nanoceramics have been synthesized using the organic sol-gel process and calcined at 600 o C. The nanoceramics were explored by X-ray powder diffractometry (XRD), transmission electron microscopy (TEM)), Fourier transforms infrared spectroscopy (FT-IR), UV–visible diffuse reflectance spectra (DRS), and electrochemical techniques including cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS). The FTIR results confirmed the presence of calcium phosphate (CP) and CP coated with Cu-ferrite (0-30 mol% Cu:Fe 3 O 4 ) core-shell nanoceramics. TEM analysis displayed nanospheres of calcium phosphate shielded with a porous spheres-like morphology with internal nanoparticles of about 33 nm. The reflectance spectra increase for all samples with increasing wavelength. Both direct and indirect gap transitions were detected with lower values of the direct case than the indirect type. The dielectric constant, refractive index, and optical electronegativity of all samples were calculated. When the ferricyanide was applied as the standard redox probe for the electrochemical characterization, CV and EIS results revealed a remarkable enhancement in the generated electrochemical signals. Moreover, modified screen-printed electrodes with the 20 Cu-CPF produced the highest redox current (0.198 mA) towards the direct oxidation of hydrogen peroxide. The obtained interesting features nominate the newly developed core-shell calcium phosphate/Cu x Fe 2-x O 4 nanoceramics as promising candidates for talented magneto-optical and peroxide sensor applications.

A facile sol–gel synthesis and characterization of europium (Eu) doped β-Bi2Mo2O9 nanoparticles with remarkably enhanced photocatalytic activity for waste-water treatments

• The pure and Eu doped β-Bi 2 Mo 2 O 9 nanoparticles were synthesised via sol gel method using acid medium and water medium. • Single phase β - Bi 2 Mo 2 O 9 formation and porous natured self-assembly was confirmed with XRD, SEM and Raman. • Eu doped Bi 2 Mo 2 O 9 shows enhanced photocatalytic activity thereby degrading the Methylene blue completely when compared to pure sample. A facile sol-gel technique was employed to synthesize the nanoparticles of β-Bi 2 Mo 2 O 9 in acidic and water medium and Eu doped β-Bi 2 Mo 2 O 9 in acidic medium. The crystalline structure of the synthesized nanoparticles was characterized by powder X-ray Diffractometry, thereby confirming the monoclinic structure of pure β-Bi 2 Mo 2 O 9 and Eu-doped β-Bi 2 Mo 2 O 9 . Raman analysis was performed to verify the phase purity and to identify the vibrational modes of synthesized pure and doped molybdates. The surface morphology of synthesized particles was examined using scanning electron microscopy, which shows the formation of a honeycomb-like structure with numerous pores. UV-visible spectroscopy and XPS studied the optical properties of synthesized nanoparticles. The dye degradation process demonstrated the photocatalytic activity under visible light radiation in which Methylene blue acts as a model dye. The change in the absorbance of the dye with synthesized β-Bi 2 Mo 2 O 9 and Eu-doped β-Bi 2 Mo 2 O 9 with different concentrations of Eu 3+ was studied by a UV-Visible spectrophotometer. The results indicate that the water-based β-Bi 2 Mo 2 O 9 shows more dye degradation than acidic-based β-Bi 2 Mo 2 O 9 . The doping of Eu3+ increased the photocatalytic activity of acidic-based β-Bi 2 Mo 2 O 9 synthesis, and the efficiency increased with an increase in the doping percentage of Eu 3+ . The 10% Eu:Bi 2 Mo 2 O 9 completely degraded the Methylene Blue dye (100%) within a period of 4hours.

Facile synthesis of graphene based mixed metal sulphide nanocomposite for energy storage applications

Supercapacitors, often referred to as electrochemical capacitors, are becoming more and more common because of their high-power density, long lifespan, and low maintenance requirements. The cobalt sulphide, nickel sulphide, and graphene oxide (CoS/NiS/GO) nanocomposites were developed because of their low cost and superior electrochemical characteristics for use in supercapacitors. Powder X-ray diffractometry and X-ray photoelectron spectroscopy analyses were used to assess the phase purity of each material. Scanner electron microscopy (SEM)/energy dispersive X-ray analysis (EDX) and transmission electron microscope (TEM) images were used to visualize the nanoscale morphology of the synthesized nanocomposite. With a standard three-electrode setup, platinum sheet was used as the counter electrode and Ag/AgCl was used as the reference electrode for all electrochemical studies. The working electrode was a composite made of graphene oxide on CoS, NiS, and nickel foam. In a solution of 3 M KOH, all electrochemical measurements were conducted. In comparison to the corresponding Rct (41.35 Ω.cm2) and Rf (55.62 Ω.cm2) for the GO electrode, the Rct and Rf for the CoS/NiS/GO electrode were found to be 1.99 Ω.cm2 and 2.70 Ω.cm2, respectively. This suggests that the CoS/NiS/GO electrode has significantly lower overall impedance, which could be one of the major contributing factors to the enhanced electrochemical performance of the CoS/NiS. The electrode made of CoS/NiS/GO nanocomposite has a specific capacitance of 1114 mAh/g at current density of 5 A/g. After 8000 charge-discharge cycles, CoS/NiS/GO electrodes with a current density of 5 A/g still had 80% of their original specific capacitance. The CoS/NiS/GO samples have been shown to have energy densities and power densities of 674.12 Wh/kg and 8089.44 W/kg, respectively. Galvanostatic charge/discharge experiments reveal that the CoS/NiS/GO nanocomposite has a high specific capacitance and a long cycle life.

Insights into the Role of Compendial/Biorelevant Media on the Supersaturation Behaviour of Drug Combination (Drug-Drug Interaction) and Precipitation Inhibition by Polymers.

Combination drug therapy (CDT) plays an immense role in the treatment of various diseases such as malaria, hypertension, cancer, HIV-AIDS, helminthiasis, and many more. However, in vitro drug-drug interaction (DDI) is not well reported for better efficacy of CDT. In DDI one drug may enhance the precipitation of other drugs thereby reducing the advantage of CDT. Herein, we report DDI in terms of in vitro precipitation of drugs with albendazole and mebendazole. This may be the first report to propensate the possibility of either drug precipitation in the combination. These drugs are categorized into BCS class II weak base and hence have tendency to precipitate in the gastrointestinal tract. The objective of this study is to find precipitation of drug combinations in different compendial and biorelevant media (deionized water, phosphate buffer pH 6.8, FaSSIF, and FeSSIF) and screening of the polymers for precipitation inhibition. Nine polymers were investigated at three different concentrations in terms of their drug-polymer solubility, in vitro precipitation behavior, induction time, SHC, and droplet size. Although, all the polymers inhibit the precipitation of drugs, the extent of precipitation inhibition for Soluplus is high. The obtained drug-polymer precipitates were filtered, dried, and analyzed for amorphous/partial amorphous form using polarised light microscopy (PLM), differential scanning calorimetry (DSC), and powder X-ray diffractometry (PXRD). The drug-polymer interaction was examined using Fourier transform infrared (FTIR) spectroscopy and nuclear magnetic resonance (NMR) revealing the effect of polymers on drug precipitation. These insights may further be used in the formulation of CDT for helminthiasis management.

Physicochemical and Pharmacokinetic Evaluation of Praziquantel Co-Crystals by Varying the Spacer Group of Co-Crystal Formers

The research work focuses on investigating the effects of spacer group (varying aliphatic chain length=n) of co-crystal formers (oxalic acid (OA, n=0), (malonic acid (MA, n=1), (succinic acid (SA, n=2), (glutaric acid (GA, n=3), and (adipic acid (AA, n=4) on the physicochemical properties and oral bioavailability of praziquantel (PZQ) co-crystals. For this purpose, different co-crystals of PZQ with dicarboxylic acid co-crystal formers (OA, MA, SA, GA, and AA) were synthesized. These co-crystals were characterized by powder X-ray diffractometry (XRPD), differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FT-IR), and thermogravimetry (TG) techniques. The in-vitro (solubility and dissolution) and in-vivo pharmacokinetic (P.K) studies were performed for PZQ co-crystals. Additionally, the effect of polymer hydroxypropyl cellulose (HPC) on the formation of PZQ co-crystals was also investigated. According to the study results, PZQ-SA co-crystal showed improved solubility, dissolution, and oral bioavailability. Overall, the solubility, dissolution, and oral bioavailability are consistent with each other. The order of improved solubility, dissolution, and oral bioavailability is observed as consistent like PZQ-SA > PZQ-AA > PZQ-GA > PZQ-OA > PZQ-MA > pure PZQ. Concerning HPC polymer effects, PZQ-OA, PZQ-MA, PZQ-GA, and PZQ-AA co-crystals were formed successfully in the presence of HPC polymer but the PZQ-SA co-crystal was inhibited.

용해도가 개선된 엔잘루타마이드 고체분산체 함유 정제의 개발

The objective of this study was to develop a novel enzalutamide tablet formulation with enhanced solubility and bioavailability, and inhibited recrystallization. Kollidon VA64 was selected as a soluble polymer for preparing enzalutamide solid dispersions. Solid dispersions with different enzalutamide to Kollidon VA64 weight ratios were prepared via solvent evaporation method. The enzalutamide solid dispersion consisting of enzalutamide and Kollidon VA64 at a weight ratio of 1:1, exhibited an excellent dissolution rate and potent inhibition of recrystallization. Enzalutamide solid dispersions were characterized by scanning electron microscopy, powder X-ray diffractometry, differential scanning calorimetry, and in vitro dissolution studies. The 1:1 solid dispersion exhibited excellent productivity, an elevated dissolution rate, and recrystallization inhibition. Therefore, enzalutamide solid dispersion loaded tablets were prepared and their dissolution was evaluated compared to a commercial product (Xtandi® soft capsule). The selected tablet formulation containing enzalutamide solid dispersion exhibited a higher dissolution rate in pH 1.0 solution than did the Xtandi® soft capsule, and prevented recrystallization of the enzalutamide. This research suggests that enzalutamide-containing solid dispersion tablets could be the most effective method to date for improving the dosing compliance of Xtandi® soft capsules, improving the dissolution rate of enzalutamide, and preventing recrystallization.

Micromechanical properties of hydroxyapatite nanocomposites reinforced with CNTs and ZrO2

This study examined the mechanical properties, wettability, and tribology of hydroxyapatite (HA)–zirconia (ZrO2)–carbon nanotube (CNTs) ceramic nanocomposites (with various CNT ratios (x): 1, 5, and 10 wt%). HA–ZrO2–CNT-x powders were hydrothermally synthesized. Hot isostatic pressing (HIP) and cold isostatic pressing were used to manufacture solid and dense tablets; consolidation was performed by sintering the nanocomposites under Ar gas at 1150 °C during HIP. The microstructure and morphology of the nanocomposites were characterized via transmission electron microscopy, energy-dispersive X-ray spectroscopy, powder X-ray diffractometry, Fourier transform infrared (FTIR), and scanning electron microscopy. The effects of ZrO2 and CNTs on the mechanical characteristics of the nanocomposites were examined via nanoindentation, reciprocating wear, and Vickers hardness tests. The microhardness of HA–ZrO2–CNT-1% and HA–ZrO2–CNT-5% increased by 36.8% and 66.67%, respectively, compared with that of pure HA. The nanohardness of the HA–ZrO2–CNT-1%, HA–ZrO2–CNT-5%, and HA–ZrO2–CNT-10% samples was 8.3, 9.65, and 8.02 Gpa, and the corresponding elastic modulus was 83.72, 114.34, and 89.27 GPa, respectively. Both of these parameters were higher than those of pure HA. However, in the nanocomposite reinforced with 10% CNT, as opposed to those with lower CNT ratios, their values were lower. Additionally, HA–ZrO2–CNT-10% was the most hydrophilic nanocomposite synthesized in this study with a contact angle of 48.8°.

Effect of Bi3+ incoporation on up/downconversion luminescence and photocatalytic activity of Gd2O3

Gd2O3 has been selected as host material for optical studies due to its good chemical, photothermal, and photochemical stabilities. A series of (Gd1-xBix)2O3 (x = 0.03, 0.05, 0.1, 0.2, 0.3, 0.5) samples were obtained via coprecipitation method. The samples were characterized by X-ray powder diffractometry (XRD), transmission electron microscopy (TEM) combined with selected area electron diffraction (SAED), BET surface area method, UV-visible (UV–vis) absorption spectra and photoluminescence (PL) spectroscopy. The crystalline-to-amorphous phase transformation was found with higher concentration of Bi3+ incorporation. The dependence of Bi3+ concentration on the upconversion/downconversion luminescence intensity were investigated and the photocatalytic activity of the synthesized samples was also evaluated by the degradation of Rhodamine B (RhB) dye in aqueous solution under visible light irradiations. The samples (Gd0.5Bi0.5)2O3 exhibited better photocatalytic activity for RhB degradation than Gd2O3 and Bi2O3 due to phase transformation, modified band structures and higher surface area.

The Optimization and Evaluation of Flibanserin Fast-Dissolving Oral Films.

Flibanserin (FLB) is a drug used for female hypotensive sexual desire disorder approved by the FDA in August 2015. FLB exhibits extensive hepatic first-pass metabolism and low aqueous solubility, hence poor oral bioavailability. In this study, beta hydroxypropyl cyclodextrin-FLB inclusion complexes were incorporated into orally fast dissolving films. This dosage form was expected to improve FLB aqueous solubility, which would give fast onset of action and decrease presystemic metabolism, hence improving oral bioavailability. The inclusion complex at a ratio of 1:1 was prepared by the kneading method. Differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR), and powder X-ray diffractometry (XRD) were used to confirm complex formation. The Box–Behnken design (15 different formulae of FLB fast-dissolving oral films (FLBFDOFs) were utilized for the optimization of the prepared films. The Expert Design 11 program was utilized to examine the effects of three selected factors, polymer concentration (X1), plasticizer concentration (X2), and disintegrant concentration (X3) on four responses: disintegration time (DT), initial dissolution rate (IDR), dissolution efficiency (DE), and film quality (QF). Numerical optimization was performed by minimizing disintegration time (Y1), while maximizing the initial drug dissolution rate (Y2), dissolution efficiency (Y3), and the quality factor (Y4). The statistical analysis showed that X1 has a significant positive effect on the disintegration time and a significant negative effect on IDR. While X2 and X3 produced a nonsignificant negative effect on IDR. Dissolution efficiency was maximized at the middle concentration of both X2 and X3. The best film quality was observed at the middle concentration of both X1 and X2. In addition, increasing X3 leads to an improvement in film quality. The optimized film cast from an aqueous solution contains hydroxypropyl cellulose (2%) as a hydrophilic film-forming agent and propylene glycol (0.8%) as a plasticizer and cross povidone (0.2%) as a disintegrant. The prepared film released 98% of FLB after 10 min and showed good physical and mechanical properties. The optimized formula showed a disintegration time of 30 s, IDR of 16.6% per minute, DE15 of 77.7%, and QF of 90%. This dosage form is expected to partially avoid the pre-systemic metabolism with a fast onset of action, hence improving its bioavailability that favors an advantage over conventional dosage forms.

Improved Stability of Platinum Oxygen Reduction Reaction Catalysts by Implementation of Thermally Treated Carbon Supports with High Biomass Content

To improve the lifetime of polymer electrolyte membrane fuel cells (PEMFCs), optimization of the fuel cell components is necessary wherein one research focus is the stability of the platinum catalyst support. Due to the harsh conditions in PEMFCs, e.g. high potentials (≥ 0.85 VRHE) and low pH (≤ 2), the catalyst support, which commonly consists of a high surface area carbon, degrades.[1] This is mainly caused by carbon corrosion, which becomes significant at potentials above 1.1 VRHE.[2] Typically, commercially available and chemically derived raw oil based carbons are used as catalyst supports. The use of multi-walled carbon nanotubes (MWCNTs) as a more stable, graphitic catalyst support with high electrical conductivity is well known in literature.[3, 4] The production of MWCNTs is expensive, which makes upscaling difficult. However, a previous study of our group Schonvogel et al. showed low stability of biomass-based supports, which requires further optimization.[5] Therefore, an approach to increase the stability of the biomass-based carbon support is thermal graphitization to generate a stable and ordered carbon structure. This leads to an increased amount of sp2-hybridized carbon with increased crystallinity and increased graphitic degree. At this point, the use of activated biomasses as carbon support is a cheap and sustainable alternative to MWCNTs and commercially available carbon blacks, for example Vulcan XC-72®.[5, 6] In this work, novel composite supports using thermally treated activated sawdust and MWCNTs will be investigated as Pt-nanoparticle support towards their physical properties and electrochemical ORR activity and stability. Sawdust was steam activated at 750 °C for 1 h in nitrogen atmosphere to create a defined pore system. Afterwards, the activated sawdust (aSD) was mechanically mixed with 20 wt.% MWCNTs. The mixture was treated at high temperatures (1500, 1800 and 2100 °C, under Ar atmosphere) in a furnace. For comparison, MWCNTs only were thermally treated under the same conditions. Physical characterization of the supports was performed using low temperature nitrogen sorption for determination of surface properties and crystallinity powder x-ray diffractometry (PXRD) for analysis of the degree of graphitization. Next, these novel carbon materials were used as support for 40 wt.% platinum nanoparticles. The platinum content was determined using inductive coupled plasma with mass spectrometry (ICP-MS) and the platinum nanoparticle diameter was analyzed with transmission electron microcopy (TEM) resulting in mean diameters ≤ 2 nm. In order to evaluate the activity and stability of the synthesized platinum catalysts, electrochemical characterization was performed for most promising catalysts before and after an accelerated stress test (AST, 0.6 – 1.5 VRHE, 500 mV s-1, 5000 cycles). For electrochemical characterization a three-electrode setup with a rotating ring disc electrode (RRDE) was used. The electrochemical active surface area was obtained by hydrogen underpotential deposition (HUPD) and CO stripping method. In Figure 1 the ORR curves, mass activities (MA) determined at 0.9 VRHE and MA loss of Pt/gaSD_gMWCNTs_2100 and Pt/gMWCNTs_2100 before and after AST are shown.Our study reveals that the mixture of 20 wt.% MWCNTs with sustainable aSD and subsequent thermal treatment results in a catalyst with comparable MA and stability to Pt/MWCNTs_2100. Thus, the use of activated biomass as the main component in catalyst supports constitute a more sustainable and cheaper alternative to MWCNTs. Based on these results, thermal treatment at higher temperatures of ≥ 2500 °C and higher biomass content will be further investigated to increase the stability.[1] F. Ettingshausen, J. Kleemann, A. Marcu, G. Toth, H. Fuess, C. Roth, Fuel Cells 2011, 11, 238-245.[2] V. Bandlamudi, P. Bujlo, C. Sita, S. Pasupathi, Materials Today: Proceedings 2018, 5, 10602-10610.[3] V. N. Popov, Materials Science and Engineering: R: Reports 2004, 43, 61-102.[4] D. Schonvogel, J. Hülstede, P. Wagner, I. Kruusenberg, K. Tammeveski, A. Dyck, C. Agert, M. Wark, J. Electrochem. Soc. 2017, 164, F995-F1004.[5] D. Schonvogel, M. Nowotny, T. Woriescheck, H. Multhaupt, P. Wagner, A. Dyck, C. Agert, M. Wark, Energy Technology 2019, 7, 1900344.[6] M. Iwanow, T. Gartner, V. Sieber, B. Konig, Beilstein J Org Chem 2020, 16, 1188-1202. Figure 1

Swelling and Salt Formation in Ibuprofen and Tranexamic Acid-Containing Tablets during High-Temperature Storage

Ibuprofen (IBP)- and Tranexamic acid (TXA)-containing tablets are known to swell when stored at high temperatures, but the mechanism of swelling is unknown. In this study, we investigated the possible mechanism of swelling with high-temperature storage. Differential scanning calorimetry (DSC) and powder X-ray diffractometry (PXRD) analyses showed that a new complex was formed in swollen tablets, when stored at 50 °C for 60 days. Additionally, we prepared single crystals of IBP and TXA, and analyzed them using single crystal X-ray diffractometry (SCXRD), to identify the new complex formed during storage. This revealed that the single crystal was a salt consisting of IBP and TXA. The PXRD peak of the salt simulated by SCXRD matched that of the PXRD peak of the swollen tablet after storage. These results suggest a close relationship between the swelling and crystal structures of IBP and TXA.

Preparation, Characterization and Evaluation of Prasugrel Hydrochloride Nanosuspensions: Its enhancement of dissolution rate and oral bioavailability

The objective of this study was to investigate nanosuspensions for enhancing the solubility and dissolution rate of Prasugrel HCl (PHCl) so as to reduce the fluctuations in its oral bioavailability. Prasugrel Hydrochloride nanosuspensions were prepared using evaporative precipitation method. After preparation, various nanosuspensions were characterized for particle size, scanning electron microscope (SEM), zeta potential, drug entrapment efficiency (EE), Fourier transform infrared spectroscopy (FTIR), and differential scanning calorimetry (DSC). Solubility and in-vitro release of the drug from nanoparticles are determined. The formulations were characterized using techniques such as powder x-ray diffractometry, scanning electron microscopy, in-vitro dissolution and in-vivo absorption in rats. The dissolution rate and oral absorption of Prasugrel Hydrochloride in the form of nanosuspensions was significantly higher than that of oral suspension and pure drug. All the techniques investigated in this study can be used to enhance dissolution rate and oral absorption of prasugrel hydrochloride and thus can reduce the fluctuations in its oral bioavailability. Nanosuspensions demonstrated to be better and superior technique when compared to other techniques investigated in enhancing oral bioavailability of Prasugrel Hydrochloride. Prasugrel hydrochloride nanosuspension was successfully developed using and the bioavailability is 4 folds increased than its pure drug.

Application of competitive adsorption of ethylenediamine and polyetheramine in direct float of quartz from quartz-feldspar mixed minerals under neutral pH conditions

Flotation is the most effective way to separate quartz and feldspar, but conventional flotation is usually achieved under acidic or alkaline conditions, which causes pollution to the environment. This study proposes a new method for a direct float of quartz from quartz-feldspar mixed minerals under neutral pH conditions. The method achieves the separation of minerals by competitive adsorption of ethylenediamine (EDA) and polyetheramine (PEA) on the particle surface. The effect of EDA and PEA on the separation of the quartz and the feldspar was investigated by flotation experiments. Using Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), X-ray powder diffractometry (XRD), Inductively coupled plasma-optical emission spectrometry (ICP-OES), and X-Ray Fluorescence Spectrometer (XRF) tests, the flotation behavior, and adsorption mechanism were analyzed. The result of the flotation experiments of a single mineral shows that EDA can effectively depress the flotation of the feldspar and enlarge the difference between the flotation recovery of the quartz and the feldspar, up to Δ = 77%. The result of flotation experiments of the mixed minerals shows that the combination of EDA and PEA can effectively separate the quartz and the feldspar. For the froth products, the quartz content of 2-F-Qtz reaches 97.42% and the SiO2 grade is 99.12% at a quartz flotation recovery of 70.20%. For the sink products, the feldspar content of 4-S-Fsp reaches 94.77% and the SiO2 grade is 69.50% at a feldspar flotation recovery of 87.45%. A competitive-adsorption model is proposed to explain the mechanism of the direct float of the quartz from the quartz-feldspar mixed minerals under neutral pH conditions.

Cellulose from Annual Plants and Its Use for the Production of the Films Hydrophobized with Tetrafluoroethylene Telomers

Cellulose HogC was produced by the modified traditional method with 35% yield from the stem of Sosnovsky hogweed and was characterized by elemental analysis, infrared (IR) spectroscopy, powder X-ray diffractometry, differential scanning calorimetry (DSC) and X-ray photoelectron spectroscopy (XPS). For HogC, the degree of crystallinity (approximately 70%) and the glass transition temperature (105–108 °C) were determined. It was found that the whiteness characteristic in the case of HogC was 92% and this significate was obtained without a bleaching procedure using chlorine-containing reagents. In this paper, the possibility of hydrophobization of HogC films by treatment with radiation-synthesized telomers of tetrafluoroethylene is shown. It was found that the contact angle of the telomer-treated cellulose film surface depended on the properties of the telomers (the chemical nature of the solvent, and the initial concentration of tetrafluoroethylene) and could reach 140 degrees.

ENCAPSULATION OF EXEMESTANE WITH β-CYCLODEXTRIN AND TERNARY AGENT: FORMULATION, EVALUATION AND ANTICANCER ACTIVITY

Objective: A potent aromatase inhibitor, Exemestane, is well known for its anticancer action in breast neoplasm. The vital problem of this medicament is its poor aqueous solubility, which hinders its dissolution in body fluids. Therefore, the present study targets to enhance the water solubility of Exemestane by means of its complexation with β-cyclodextrin and a suitable ternary agent. Methods: Inclusion complexes of Exemestane with β-cyclodextrin and ternary agent were prepared by kneading and lyophilization technique. Different hydrophilic polymers and organic acids were screened for their influential ability as a co-complex with a carrier; β-cyclodextrin. The validation of complex formation was carried out by various solid-state techniques. The geometry of Exemestane in the β-cyclodextrin cavity was picturized in docking studies. The in vitro anticancer activity of prepared inclusion complex formulations carried out using MCF-7 cell lines Results: Phase solubility analysis proved HPMC E5 as the best ternary agent for complexation of Exemestane with β-cyclodextrin as it improved the stability constant of the drug from 665.92 M-1 to 1238.38 M-1. The synthesized binary and ternary inclusion complexes exhibited 2.74 and 4.62 times enhanced solubilization of Exemestane. Likewise, the dissolution characteristics of Exemestane were improved, and drug release was increased by 1.18 and 1.42 times with binary and ternary freeze-dried formulations. Differential scanning calorimetry (DSC) and powder X-ray diffractometry (PXRD) study results presented the formation of binary and ternary complexes with significantly drooped crystallinity. Docking studies predicted encapsulation of rings A, B, and C of Exemestane in the cavity of β-cyclodextrin. In-line results were obtained in Fourier transform infrared (FTIR) studies. The cell growth inhibition of 62.78 % was achieved with a ternary complex of Exemestane which was far superior than the pure active moiety that showed mere 44.56 % of inhibition. Conclusion: Altogether, it can be concluded that the inclusion complex of Exemestane boosted its aqueous solubility, resulting in its increased dissolution and in vitro anticancer activity in a breast cancer MCF-7 cell line.

Ways of Rare Earth Elements Migration and Transportation to the coals of the Shubarkol Deposit

The article presents the results of studying the mineralogical and geochemical features of coals and clay interlayers of the Shubarkol deposit. There were analyzed 71 samples of clay layers and 49 samples of coal using the instrumental neutron activation analysis (INAA), powder X-ray diffractometry, and scanning electron microscopy. A comprehensive analysis of the geochemical and mineralogical characteristics of coals and their enclosing clay interlayers was carried out. A variety of geochemical criteria made it possible to establish the facts of the rare earth elements (REE) migration, and the latest data of mineralogy made it possible to establish the ways of their transportation to the paleobasin in the syn- and epigenetic periods of the Shubarkol deposit formation. The data of the paleoclimate and water composition of the paleobasin of peat formation are presented for the first time. Among other things, the analysis made it possible to identify a number of independent sources and various mechanisms of REE accumulation in the sediments of the Shubarkol deposit. The main patterns of the REE distribution that are expressed in the predominance of light lanthanides over heavy lanthanides, were established, and the role and composition of the rocks surrounding coal deposits in the concentration of REE were considered. Aluminosilicates, sulfides, and sulfates with inclusions of microparticles of rare and rare-earth REE elements were found in coals and clay interlayers.

Engineering Co3O4 with Co defects for highly sensitive nonenzymatic detection of glucose

Defect engineering was considered as an effective strategy to regulate electrocatalytic activities of transition metal oxides. However, there are seldom reports about metal defects in electrochemical sensing. In this work, Co-defected Co3O4 was synthesized via thermal treatment of glycerolatocobalt (CoGly) precursor for constructing a novel electrochemical nonenzymatic glucose sensor. The obtained nanomaterials were characterized by transmission electron microscopy (TEM), powder X-ray diffractometry (XRD), Raman spectra, X-ray photoelectron spectroscopy (XPS) and electrochemical techniques. The presence of Co defects regulated electronic structure of Co3O4, which not only speeds up electron transfer rate but also exposes more high-valent Co sites, thus improving electrocatalytic activities. Under optimized conditions, Co-defected Co3O4 electrode exhibited excellent performance for glucose analysis with a wide linear range of 0.2 µM to 0.5 mM, a low detection limit of 0.16 µM. Importantly, an ultrahigh sensitivity of 2595.7 µA·mM−1·cm−2 was also obtained, which was about 10 times higher than that of conventional Co3O4. Therefore, engineering Co3O4 with Co defects is an effective strategy to tailor electrocatalytic activity, which sheds light on the potential applications of metal defects in the field of electrochemical nonenzymatic sensing.