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analysis of [Mn(NH 3 ) 6 ](NO 3 ) 2 was undertaken using the X-ray powder diffraction (XRPD) method. The XRPD data were collected with a PANalytical X’Pert PRO powder diffractometer (operating in Bragg–Brentano geometry). The measurements continued for 2 h

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Abstract  

Perovskite SrCo0.6Fe0.2Nb0.2O3-z attracts attention as a promising material with high oxygen conductivity. The sample was investigated by means of high-temperature X-ray powder diffraction and thermogravimetry. Phase transition was detected near 400 °C and accompanied with significant mass loss. The phase transition affects oxygen mobility, important for the synthesis of oxygen permeable membranes. The unit cell parameters are proved to change with temperature after two effects (1) reversible conventional thermal expansion and (2) irreversible contraction-expansion due to the changes in the oxygen content. In situ high-temperature X-ray diffraction experiments allowed us to separate the contributions and to measure them as a function of temperature.

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Abstract  

This work exemplifies a general method of studying the drug excipient interactions, with the aim of predicting rapidly and inexpensively the long term stability of their mixtures. We study the physico-chemical properties of a drug (indomethacin) in the solid state and in different combinations with several excipients (PVP=polyvinylpyrrolidone, MGST=magnesium stearate, Avicel©). We compare the properties of pure compounds (untreated, or moisture/temperature conditioned) with those of binary mixtures drug:excipient which underwent the same treatment. The purpose is to find indications of interactions within the mixtures, which means a potential incompatibility of the excipient. Both morphological and thermal properties are sensitive to interactions which leave mostly unmodified the IR spectra and the X-rays patterns. In particular, we find that indomethacin does interact with PVP and MGST, but is certainly compatible with Avicel©.

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Abstract  

We apply a range of techniques (thermal methods, microscopy, X-ray diffraction, IR spectroscopy) to characterize a drug (atenolol), several excipients (PVP=polyvinylpyrrolidone, MGST=magnesium stearate, Avicel©) and drug-excipients mixtures either as prepared, annealed, and exposed to moisture. We compare the data of the mixtures with those computed from a weighted average of similarly treated pure compounds to find evidence of drug properties modified by the interaction with the excipient. We find that thermal response is by far the most sensitive indicator of interaction while IR is the least sensitive one. Avicel© has essentially no interaction with atenolol, while MGST modifies significantly only the thermal response of the drug in the MGST-rich mixtures. PVP interacts strongly with atenolol, and this interaction appears to be mediated by the substantial amount of hydration water the excipient brings in its mixtures with a water-free drug.

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Journal of Thermal Analysis and Calorimetry
Authors: Rabia Nazir, Muhammad Mazhar, Tehmina Wakeel, Muhammad J. Akhtar, Muhammad Siddique, Muhammad Nadeem, Nawazish A. Khan, and Muhammad R. Shah

The residual shiny black mass obtained after the thermal decomposition of [Fe(bipy) 3 ]Cl 2 was subjected to elemental analysis, EDXRF, XRPD, AFM, TEM, and 57 Fe Mössbauer spectroscopy for its characterization. CHN analysis showed little

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a highly crystalline drug is of great importance, concerning drug quality and performance. Higher sensitivity of isothermal microcalorimetry (IMC), compared to analytical techniques, such as X-ray powder diffraction (XRPD) and differential

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Journal of Thermal Analysis and Calorimetry
Authors: Bogdan Tiţa, Adriana Fuliaş, Zoltan Szabadai, Gerlinde Rusu, Geza Bandur, and Dumitru Tiţa

. The purpose of this article is to evaluate the compatibility of IB with common pharmaceutical excipients, used in the solid dosage form, by TA, Fourier transformed infrared (FT-IR) and X-ray powder diffraction patterns (XRPD

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Emodin–phospholipid complex

A potential of herbal drug in the novel drug delivery system

Journal of Thermal Analysis and Calorimetry
Authors: Devendra Singh, M. S. M. Rawat, Ajay Semalty, and Mona Semalty

-chemical parameters like drug content, chemical interaction (FT-IR, 1 H-NMR), thermal behavior (DSC), crystallinity (X-RPD), surface morphology (SEM), and solubility and dissolution study. Materials and methods Materials

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Abstract  

The mixed zirconium, titanium, hafnium and first-row transition metal oxides (containing phosphorous oxide) were prepared using ion exchange method followed by calcinations at 1020 K during 12 h. The resulted mixed oxides were identified by XRPD method and studied their thermal behaviour by TG-DTA analysis. As a result of thermal analysis there were found one exothermic (with a peak at about 950 K), and one endothermic (with a peak at about 1300 K) processes, both without mass loss. The observation was valid for all investigated samples. The analysis of XRPD patterns of the investigated samples showed well-defined crystal phases characteristic of each oxide. The XRPD analysis also verified the phase transition of tetravalent metal oxides from orthorhombic to tetragonal, observed by DTA analysis.

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