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Molecules (Basel, Switzerland) Aug 2021The solvatomorphism of the anthelmintic drug moxidectin is investigated, and a new solvatomorph with nitromethane is reported. Moreover, the hitherto unknown crystal...
The solvatomorphism of the anthelmintic drug moxidectin is investigated, and a new solvatomorph with nitromethane is reported. Moreover, the hitherto unknown crystal structures of the solvatomorphs with ethanol and 2-propanol are reported and discussed. The thermal characterization of these solvatomorphs through variable-temperature powder X-ray diffraction analysis (VT-PXRD) is also described, providing new insights into the crystallochemistry of this active pharmaceutical ingredient.
Topics: Crystallography, X-Ray; Hydrogen Bonding; Macrolides; Molecular Conformation; Powder Diffraction; Solvents; Temperature
PubMed: 34443452
DOI: 10.3390/molecules26164869 -
Journal of Pharmaceutical Sciences Dec 2018Since the discovery of X-ray diffraction and its potential to elucidate crystal symmetry, powder X-ray diffraction has found diverse applications in the field of... (Review)
Review
Since the discovery of X-ray diffraction and its potential to elucidate crystal symmetry, powder X-ray diffraction has found diverse applications in the field of pharmaceutical sciences. This review summarizes significant achievements of the technique during various stages of dosage form development. Improved understanding of the principle involved and development of automated hardware and reliable software have led to increased instrumental sensitivity and improved data analysis. These advances continue to expand the applications of powder X-ray diffraction to emerging research fields such as amorphous systems, mechanistic understanding of phase transformations, and "Quality by Design" in formulation development.
Topics: Crystallization; Drug Compounding; Equipment Design; Lasers; Pharmaceutical Preparations; Phase Transition; Powder Diffraction; Small Molecule Libraries; Synchrotrons; X-Ray Diffraction
PubMed: 30145209
DOI: 10.1016/j.xphs.2018.08.010 -
Protein and Peptide Letters 2016Knowledge of 3D structures of biological molecules plays a major role in both understanding important processes of life and developing pharmaceuticals. Among several... (Review)
Review
Knowledge of 3D structures of biological molecules plays a major role in both understanding important processes of life and developing pharmaceuticals. Among several methods available for structure determination, macromolecular X-ray powder diffraction (XRPD) has transformed over the past decade from an impossible dream to a respectable method. XRPD can be employed in biosciences for various purposes such as observing phase transitions, characterizing bulk pharmaceuticals, determining structures via the molecular replacement method, detecting ligands in protein-ligand complexes, as well as combining micro-sized single crystal crystallographic data and powder diffraction data. Studies using synchrotron and laboratory sources in some standard configuration setups are reported in this review, including their respective advantages and disadvantages. Methods presented here provide an alternative, complementary set of tools to resolve structural problems. A variety of already existing software packages for powder diffraction data processing and analysis, some of which have been adapted to large unit cell studies, are briefly described. This review aims to provide necessary elements of theory and current methods, along with practical explanations, available software packages and highlighted case studies.
Topics: Macromolecular Substances; Models, Molecular; Molecular Structure; Powder Diffraction; Synchrotrons; X-Ray Diffraction
PubMed: 26786768
DOI: 10.2174/0929866523666160120152839 -
Enzyme and Microbial Technology Dec 2016The biological synthesis of nanoparticles (NPs) by bacteria and biofilms via extracellular redox reactions has received attention because of the minimization of harmful... (Review)
Review
The biological synthesis of nanoparticles (NPs) by bacteria and biofilms via extracellular redox reactions has received attention because of the minimization of harmful chemicals, low cost, and ease of culturing and downstream processing. Bioreduction mechanisms vary across bacteria and growth conditions, which leads to various sizes and shapes of biosynthesized NPs. NP synthesis in biofilms offers additional advantages, such as higher biomass concentrations and larger surface areas, which can lead to more efficient and scalable biosynthesis. Although biofilms have been used to produce NPs, the mechanistic details of NP formation are not well understood. In this review, we identify three critical areas of research and development needed to advance our understanding of NP production by biofilms: 1) synthesis, 2) mechanism and 3) stabilization. Advancement in these areas could result in the biosynthesis of NPs that are suitable for practical applications, especially in drug delivery and biocatalysis. Specifically, the current status of methods and mechanisms of nanoparticle synthesis and surface stabilization using planktonic bacteria and biofilms is discussed. We conclude that the use of biofilms to synthesize and stabilize NPs is underappreciated and could provide a new direction in biofilm-based NP production.
Topics: Bacteria; Biofilms; Electron Transport; Green Chemistry Technology; Microscopy, Electron, Transmission; Nanoparticles; Oxidation-Reduction; Powder Diffraction; Spectrum Analysis
PubMed: 27866625
DOI: 10.1016/j.enzmictec.2016.07.015 -
Journal of Pharmaceutical and... Jan 2018Spurious/Falsely-labeled/Falsified/Counterfeit (SFFC)drugs have become a major threat to public health, especially in rural areas of developing countries.The goal of... (Review)
Review
Spurious/Falsely-labeled/Falsified/Counterfeit (SFFC)drugs have become a major threat to public health, especially in rural areas of developing countries.The goal of this review is to provide an overview of rapid detection technologies for counterfeits recently reported, such as Near Infrared Spectroscopy, Near Infrared Chemical Imaging, Raman Spectroscopy, X-Ray Fluorescence, X-RayPowder Diffraction, Ion Mobility Spectrometry, Ion MobilityMass Spectrometry,Isotope Ratio Mass Spectrometry and visual analytical methods The advantages of each of these detection methods are introduced. Examples of characterization of SFFC drugs using the detection technology mentioned are presented. In addition, new characteristics and trends of SFFC drugs are listed and the solution is discussed.
Topics: Counterfeit Drugs; Developing Countries; Limit of Detection; Powder Diffraction; Spectrum Analysis
PubMed: 28844368
DOI: 10.1016/j.jpba.2017.08.016 -
Molecules (Basel, Switzerland) Nov 2022Tafamidis, chemical formula CHClNO, is a drug used to delay disease progression in adults suffering from transthyretin amyloidosis, and is marketed worldwide under...
Tafamidis, chemical formula CHClNO, is a drug used to delay disease progression in adults suffering from transthyretin amyloidosis, and is marketed worldwide under different tradenames as a free acid or in the form of its meglumine salt. The free acid (CAS no. 594839-88-0) is reported to crystallize as distinct (polymorphic) crystal forms, the thermal stability and structural features of which remained thus far undisclosed. In this paper, we present-by selectively isolating highly pure batches of Tafamidis Form 1 and Tafamidis Form 4-the full characterization of these solids, in terms of crystal structures (determined using state-of-the-art structural powder diffraction methods) and spectroscopic and thermal properties. Beyond conventional thermogravimetric and calorimetric analyses, variable-temperature X-ray diffraction was employed to measure the highly anisotropic response of these (poly)crystalline materials to thermal stimuli and enabled the determination of the linear and volumetric thermal expansion coefficients and of the related indicatrix. Both crystal phases are monoclinic and contain substantially flat and π-π stacked Tafamidis molecules, arranged as centrosymmetric dimers by strong O-H···O bonds; weaker C-H···N contacts give rise, in both polymorphs, to infinite ribbons, which guarantee the substantial stiffness of the crystals in the direction of their elongation. Complete knowledge of the structural models will foster the usage of full-pattern quantitative phase analyses of Tafamidis in drug and polymorphic mixtures, an important aspect in both the forensic and the industrial sectors.
Topics: Crystallization; Powder Diffraction; X-Ray Diffraction
PubMed: 36364244
DOI: 10.3390/molecules27217411 -
Accounts of Chemical Research Apr 2017The wide range of fascinating supramolecular architectures found in nature, from DNA double helices to giant protein shells, inspires researchers to mimic the diverse... (Review)
Review
The wide range of fascinating supramolecular architectures found in nature, from DNA double helices to giant protein shells, inspires researchers to mimic the diverse shapes and functions of natural systems. Thus, a variety of artificial molecular platforms have been developed by assembling DNA-, peptide-, and protein-based building blocks for medicinal and biological applications. There has also been a significant interest in the research of non-natural oligomers (i.e., foldamers) that fold into well-defined secondary structures analogous to those found in proteins, because the assemblies of foldamers are expected not only to form biomimetic supramolecular architectures that resemble those of nature but also to display unique functions and unprecedented topologies at the same time due to their different folding propensities from those of natural building blocks. Foldamer-based supramolecular architectures have been reported in the form of nanofibers, nanochannels, nanosheets, and finite three-dimensional (3D) shapes. We have developed a new class of crystalline peptidic materials termed "foldectures" (a compound of foldamer and architecture) with unprecedented topological complexity derived from the rapid and nonequilibrium aqueous phase self-assembly of foldamers. In this Account, we discuss the morphological features, molecular packing structures, physical properties, and potential applications of foldectures. Foldectures exhibit well-defined, microscale, homogeneous, and finite structures with unique morphologies such as windmill, tooth, and trigonal bipyramid shapes. The symmetry elements of the morphologies vary with the foldamer building blocks and are retained upon surfactant-assisted shape evolution. Structural characterization by powder X-ray diffraction (PXRD) revealed the molecular packing structures, suggesting how the foldamer building blocks assembled in the 3D structure. The analysis by PXRD showed that intermolecular hydrogen bonding connects foldamers in head-to-tail fashion, while hydrophobic attraction plays a role in arranging foldamers in parallel, antiparallel, or cholesteric phase-like manners. Each packing structure from the foldamer building blocks possesses distinct symmetry elements that are directly expressed in the 3D morphologies. Because of their well-ordered molecular packing structures, foldectures exhibit facet-dependent surface characteristics and anisotropic magnetic susceptibility. The facet-dependent surface property was harnessed to synthesize anisotropic metal nanoparticle-foldecture composites, and the anisotropic magnetic susceptibility enables foldectures to undergo real-time alignment and rotating motion in response to an external magnetic field. By means of their unusual shapes and properties, foldectures have been demonstrated to mimic the functionality of natural systems such as magnetosomes or carboxysomes. Further development of foldectures using higher-order building units, complicated packing motifs, and functional moieties could provide a novel biocompatible platform rivaling 3D biological architectures in natural systems.
Topics: Magnetospirillum; Models, Molecular; Particle Size; Peptides; Powder Diffraction; Protein Conformation; Protein Folding
PubMed: 28191927
DOI: 10.1021/acs.accounts.6b00545 -
Analytical Sciences : the International... Dec 2022The thermal behavior of stellerite from the Savinskoye deposit (Transbaikalia, Russia), CaNaK(SiAl)O·53.39HO, was investigated by in situ high-temperature X-ray powder...
The thermal behavior of stellerite from the Savinskoye deposit (Transbaikalia, Russia), CaNaK(SiAl)O·53.39HO, was investigated by in situ high-temperature X-ray powder diffraction (HTXRPD) and ex situ HT infrared (IR) spectroscopic analysis. Four different HTXRPD experimental procedures were used to study the thermal behavior of the powder samples: (1) RT-750 °C, (2) RT-220 °C -RT, (3) 200-350-RT °C, and (4) 350-700 °C. Electron probe microanalysis and single-crystal X-ray diffraction were preliminary used to determine the chemical composition and crystal structure of stellerite. The A → B phase transition (Fmmm → Amma) starts at ∼110 °C and is completed at about 140 °C (in situ HTXRPD) and 200 °C (ex situ HTIR) depending on the experimental conditions. It involves a cell volume decrease of 5.8% (Experiment 1). The thermal expansion of stellerite is more pronounced along the b and c axes, with αa: αb: αc (× 10) = 2.50:-25.52:-6.84 at 100 °C, 0.44:-21.75:-25.64 at 150 °C after the completion of the phase transition, and 3.06:-1.86:-16.94 at 500 °C. The reverse B → A transition occurs at temperatures below 100 °C during slow cooling (Experiment 2), however, it does not occur upon rapid cooling (Experiment 3). The B → D phase transition above 300 °C is not observed (Experiment 4). The temperature barrier of phase transition in the ex situ HTIR spectroscopy experiment is shifted towards high temperatures. The heating above 200 °C leads to an increase of 3430 cm and a decrease of 3600 and 3260 cm bands, which correspond to the stretching vibration of HO. The heating above 400 °C causes complete dehydration of the stellerite.
Topics: X-Ray Diffraction; Temperature; Powders; Powder Diffraction; X-Rays
PubMed: 36094727
DOI: 10.1007/s44211-022-00186-4 -
International Journal of Cosmetic... Feb 2021In the present study, we describe the features and functional properties of a new powder cosmetic ingredient, an amorphous mesoporous magnesium carbonate (MMC, also...
OBJECTIVE
In the present study, we describe the features and functional properties of a new powder cosmetic ingredient, an amorphous mesoporous magnesium carbonate (MMC, also named Upsalite ) with regard to physical characteristics as well as functional attributes.
METHODS
Physical and functional characterization of MMC, as compared to other common powder cosmetic ingredients (silica, mica, kaolin, talc and starch), was assessed using nitrogen gas adsorption, powder X-ray diffraction, particle size distribution by laser diffraction, scanning electron microscopy (SEM), and oil and moisture uptake tests. The powder ingredients were also applied on human skin and analysed for short- and long-term mattifying effect, and a new method was developed to measure flashback effect. MMC was tested for skin irritation using an in vitro cell model as well as in vivo, through the Human Repeated Insult Patch Test on 50 human volunteers.
RESULTS
Mesoporous magnesium carbonate has a high surface area and pore volume. It has an excellent absorption capacity and can take up both oil and water simultaneously. It provides instant and long-lasting mattifying effect when applied on human skin without drying or irritating skin and exhibits no measured flashback effect.
CONCLUSION
Mesoporous magnesium carbonate has good sensory and visual characteristics as well as excellent absorbing and mattifying properties, suggesting that it has great potential to replace other powder ingredients currently used as fillers and absorbers in powder cosmetics.
Topics: Cosmetics; Humans; Irritants; Magnesium; Porosity; Powder Diffraction; Powders; Skin
PubMed: 33038019
DOI: 10.1111/ics.12670 -
Journal of Pharmaceutical and... Feb 2017Solvent free mechanochemical approach is utilized to synthesise new cocrystals of chrysin using supramolecular chemistry based upon reliable synthons. Chrysin, a flavone...
Solvent free mechanochemical approach is utilized to synthesise new cocrystals of chrysin using supramolecular chemistry based upon reliable synthons. Chrysin, a flavone nutraceutical with wide range of beneficial effects has critically low bioavailability on account of its poor aqueous solubility and consequently poor absorption from the gastrointestinal tract. The present study focuses on this critical aspect and has exploited non covalent interactions to prepare its cocrystals with cytosine and thiamine hydrochloride. Various techniques were used for characterization including Differential Scanning Calorimetry (DSC), Fourier Transform Infrared Spectroscopy (FT-IR), Solid State NMR Spectroscopy (SSNMR) and Powder X-Ray Diffraction (PXRD). The molecules in the cocrystals crystallized in neutral forms and assembled in a molecular layer by means of hydrogen bonding which was confirmed by structural characterization. The cocrystals share a common supramolecular motif being the OH⋯N interaction, involving phenolic moiety of C7 functionality of the parent molecule. Approximately 3-4 fold increase in solubility and dissolution profile of cocrystals was observed which was further corroborated by improved in vitro and in vivo activities including antioxidant, antihaemolytic and anti-inflammatory thus, opening a new viable technique for the exploitation of useful phytonutrients.
Topics: Animals; Anti-Inflammatory Agents; Antioxidants; Calorimetry, Differential Scanning; Crystallization; Drug Evaluation, Preclinical; Flavonoids; Magnetic Resonance Spectroscopy; Male; Powder Diffraction; Rats; Rats, Wistar; Spectroscopy, Fourier Transform Infrared; X-Ray Diffraction
PubMed: 27894779
DOI: 10.1016/j.jpba.2016.10.020