Structural Characterization of Albendazole with the Use of X-Ray Diffraction

Drugs may present polycrystalline polymorphism (property of a substance to crystallize in more than one form or crystal structure). These variations can cause changes in physical-chemical properties and differences between the polymorphs as shape, solubility, density, melting range, among other consequences, leading to formulations that are not effective, although the chemical formula is the same [1]. Drugs such as albendazole (C12H15N3O2S, which is one of the most effective anthelmintics, [2] showing activity against nematodes, trematodes and cestodes, reasons that added to its safety and low cost have made it a drug widely used in human medicine and veterinary), has more than two different crystal structures, and only two of them are known. The X-ray powder diffraction is a powerful technique used in the structural characterization of drugs, and coupled with the Rietveld method [4], the quantification of the active phases, through the knowledge of their crystal structures, becomes possible. In this paper we discuss results on the differences between the polymorphs of albendazole, with data obtained by means of X-ray diffraction, thermal analysis (differential scanning calorimetry and thermogravimetric analysis), Fourier transform infrared spectroscopy and scanning electron microscopy.

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Thermal analysis combined with X-ray diffraction/Rietveld method, FT-IR and UV-vis spectroscopy: Structural characterization of the lanthanum and cerium (III) polycrystalline complexes

Thermochimica Acta ◽

10.1016/j.tca.2020.178662 ◽

2020 ◽

Vol 690 ◽

pp. 178662

Author(s):

K.V. Tenorio ◽

A.B. Fortunato ◽

J.M. Moreira ◽

D. Roman ◽

K.A. D’Oliveira ◽

...

Keyword(s):

Thermal Analysis ◽

Structural Characterization ◽

Rietveld Method ◽

X Ray Diffraction ◽

X Ray ◽

Vis Spectroscopy ◽

Ft Ir

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A Research on Synthesis of Microorganism Template Nano-Selenium Material

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.443.639 ◽

2013 ◽

Vol 443 ◽

pp. 639-642

Author(s):

Ya Li Zhang ◽

Wei Xia ◽

Ai Hua Ren

Keyword(s):

Low Cost ◽

Synthetic Methods ◽

X Ray Diffraction ◽

Environmental Friendliness ◽

Preparation Methods ◽

X Ray ◽

E Coli ◽

Physical Chemical ◽

Harsh Conditions

At present there are various kinds of synthetic methods of nanomaterials including physical, chemical and composite method derived from the former two kinds. However, these preparation methods require harsh conditions and produce low yield. Besides, they cause environmental pollution easily. Therefore the microorganism template synthesis is favored highly due to its rich resources, low cost and availability, environmental friendliness and unique configuration and high morphology repeatability. In this thesis E. coli strains are successfully adopted as the template to synthesize nanoselenium material. Such inspection methods as scanning electron microscope, X-ray diffraction and ultraviolet are used for the characterization of samples. It aims to explore a new synthetic green way for nanoselenium material.

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The Preparation and Characterization of Alginate–Chitosan Membranes as Solid Support for BTB and Urease Entrapment

Molekul ◽

10.20884/1.jm.2020.15.1.527 ◽

2020 ◽

Vol 15 (1) ◽

pp. 40 ◽

Cited By ~ 1

Author(s):

Dhony Hermanto ◽

Mudasir Mudasir ◽

Dwi Siswanta ◽

Bambang Kuswandi ◽

Nurul Ismillayli

Keyword(s):

Color Change ◽

Bromothymol Blue ◽

Mass Ratio ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

X Ray ◽

Chitosan Membrane ◽

Physical Chemical ◽

Chitosan Membranes

A study of alginate-chitosan membrane synthesize was done. The membrane was prepared by mixing alginate hydrosol and chitosan hydrosol at mass ratio of 1:1 and pH of 5.28 approximately. Then it was applied for matrix immobilization of urease and bromothymol blue (BTB) by entrapment technique. The physical, chemical, thermal properties of alginate–chitosan membrane and their impact on immobilized urease activity were investigated. The polymer products were characterized by Fourier Transform Infrared Spectroscopy (FTIR), X-Ray Diffraction (XRD), Thermogravimetric Analysis (TGA), Differential Scanning Calorimetry (DSC), and Scanning Electron Microscopy (SEM). It’s showed that alginate-chitosan membrane was formed by electrostatic interaction. The obtained membran has better mechanical properties than original alginat and chitosan membranes. The immobilization urease into alginate-chitosan membrane retained the catalytic activity of the enzyme, as confirmed by color change of BTB indicator after membrane was immersed in substrate solution (urea). Therefore, alginate-chitosan membrane has good characteristics as matrix of enzyme immobilization.

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Studies on the Preparation, Characterization and Solubility of -Cyclodextrin-Roxythromycin Inclusion Complexes

International Journal of Pharmaceutical Sciences and Nanotechnology ◽

10.37285/ijpsn.2009.2.2.5 ◽

2009 ◽

Vol 2 (2) ◽

pp. 523-530

Author(s):

D. Nagasamy Venkatesh ◽

S. Karthick ◽

M. Umesh ◽

G. Vivek ◽

R.M. Valliappan ◽

...

Keyword(s):

Dissolution Rate ◽

Inclusion Complexes ◽

Phase Solubility ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

X Ray ◽

Ir Studies ◽

Poorly Soluble ◽

Poorly Soluble Drug

Roxythromycin/ β-cyclodextrin (Roxy/ β-CD) dispersions were prepared with a view to study the influence of β-CD on the solubility and dissolution rate of this poorly soluble drug. Phase-solubility profile indicated that the solubility of roxythromycin was significantly increased in the presence of β-cyclodextrin and was classified as AL-type, indicating the 1:1 stoichiometric inclusion complexes. Physical characterization of the prepared systems was carried out by differential scanning calorimetry (DSC), X-ray diffraction studies (XRD) and IR studies. Solid state characterization of the drug β-CD binary system using XRD, FTIR and DSC revealed distinct loss of drug crystallinity in the formulation, ostensibly accounting for enhancement of dissolution rate.

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Born out of Fire and Ice: Polymorph Studies of the Antiviral Famciclovir

Crystals ◽

10.3390/cryst11020129 ◽

2021 ◽

Vol 11 (2) ◽

pp. 129

Author(s):

Liana Vella-Zarb ◽

Ulrich Baisch

Keyword(s):

Variable Temperature ◽

Chemical Properties ◽

Crystal Form ◽

X Ray Diffraction ◽

Crystal Forms ◽

X Ray ◽

Physical Chemical ◽

Diffraction Patterns ◽

Crystalline Forms

There is much interest and focus on solid forms of famciclovir. However, in spite of the abundance of reported differences in oral bioavailability, compressibility, and other physical–chemical properties of the various crystal forms of this drug, very little precise structural analysis is available in the literature to date. The form used in the commercial formulation is the anhydrous form I. Patents and patent applications report three different anhydrous crystalline forms on the basis of unindexed powder diffraction patterns. Single-crystal and variable-temperature X-ray diffraction experiments using the commercially available anhydrous form of famciclovir were carried out and led not only to the crystal structure determination of the anhydrous form I, but also to discovery of a new crystal form of anhydrous famciclovir from powder data.

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Quantitative Characterization of Hydration of Cement Pastes by Rietveld Phase Analysis and Thermoanalysis

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.539.19 ◽

2013 ◽

Vol 539 ◽

pp. 19-24 ◽

Cited By ~ 1

Author(s):

Yong Qi Wei ◽

Wu Yao

Keyword(s):

Phase Analysis ◽

Cement Paste ◽

Rietveld Method ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

Quantitative Characterization ◽

Cement Pastes ◽

Hydration Mechanism ◽

Spot Check

The quantitative characterization of hydration of cement pastes has always been one of focuses of researchers’ attention. Rietveld phase analysis (RPA), a combination of quantitative X-ray diffraction (QXRD) and the Rietveld method, supplies a tool of an enormous potential for that. Although a few of related researches were conducted by RPA, the reported attention was not paid to the neat cement paste with a low w/c ratio. Therefore, this work aimed at the quantitative study on hydration of such a cement paste chiefly by this method, meanwhile, cooperated with the hyphenated technique of thermogravimetry with differential scanning calorimetry (TG-DSC), as a spot check. Results indicated that RPA was a reliable method in quantitatively characterizing hydration of cement pastes, and gave a clear decription of evolution of all main crystal phases in cement pastes; and that the evolution of monosulphate(Afm_12) was also able to be tracked quantitatively. This will help to understand better the hydration mechanism of cement pastes, as well as to investigate quantitatively effects of mineral and chemical admixtures on hydration of composite cementitious systems.

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