scholarly journals Release of Cationic Drugs from Charcoal

Materials ◽  
2019 ◽  
Vol 12 (4) ◽  
pp. 683
Author(s):  
Chiara Di Ruocco ◽  
Maria Acocella ◽  
Gaetano Guerra
Keyword(s):  
Hydrogen Peroxide ◽  
Aqueous Solutions ◽  
Uv Spectra ◽  
Wide Angle ◽  
X Ray Diffraction ◽  
X Ray ◽  
Acidic Solutions ◽  
Cationic Drugs ◽  
Mild Conditions ◽  
Harsh Conditions

The goal of this research is to improve preparation of charcoal adducts in a manner suitable for cationic drug release, possibly using an eco-friendly procedure. Charcoal, widely commercialized for human ingestion, is oxidized by hydrogen peroxide in mild conditions. Adducts of a cationic drug (lidocaine hydrochloride, a medication used as local anesthetic) with charcoal are prepared after basification of charcoal and characterized mainly by elemental analysis, wide-angle X-ray diffraction, infrared spectroscopy and thermogravimetry. The drug in the prepared adducts is present in amount close to 30% by weight and can be readily released to both neutral and acidic aqueous solutions. Cation release, as studied by UV spectra of aqueous solutions, is faster in acidic solutions and is faster than for adducts with graphite oxide, which can be prepared only in harsh conditions.

An unusual reaction of a bridged triterpenoid α-diketone with acetic anhydride

1991 ◽  
Vol 56 (12) ◽  
pp. 2917-2935 ◽  
Author(s):  
Eva Klinotová ◽  
Václav Křeček ◽  
Jiří Klinot ◽  
Miloš Buděšínský ◽  
Jaroslav Podlaha ◽  
...  
Keyword(s):  
Acetic Acid ◽  
Nmr Spectroscopy ◽  
Acetic Anhydride ◽  
Spectral Methods ◽  
X Ray Diffraction ◽  
X Ray ◽  
Mild Conditions ◽  
Condensation Products ◽  
Unsaturated Lactones ◽  
C Nmr

3β-Acetoxy-21,22-dioxo-18α,19βH-ursan-28,20β-olide (IIIa) reacts with acetic anhydride in pyridine under very mild conditions affording β-lactone IVa and γ-lactones Va and VIIa as condensation products. On reaction with pyridine, lactones Va and VIIa undergo elimination of acetic acid to give unsaturated lactones VIIIa and IXa, respectively. Similarly, the condensation of 20β,28-epoxy-21,22-dioxo-18α,19βH-ursan-3β-yl acetate (IIIb) with acetic anhydride leads to β-lactone IVb and γ-lactone Vb; the latter on heating with pyridine affords unsaturated lactone VIIIb and 21-methylene-22-ketone Xb. The structure of the obtained compounds was derived using spectral methods, particularly 1H and 13C NMR spectroscopy; structure of lactone IVa was confirmed by X-ray diffraction.

A quantitative differentiation method for plastic bags by wide angle X-ray diffraction for tracing the source of illegal drugs

2007 ◽  
Vol 168 (1) ◽  
pp. 37-41 ◽  
Author(s):  
Valerio Causin ◽  
Carla Marega ◽  
Pietro Carresi ◽  
Sergio Schiavone ◽  
Antonio Marigo
Keyword(s):  
Illegal Drugs ◽  
Wide Angle ◽  
X Ray Diffraction ◽  
X Ray ◽  
Differentiation Method ◽  
Plastic Bags

Wide angle X-ray diffraction study of the solid-phase chlorinated poly(ethylene)

Polymer ◽  
2004 ◽  
Vol 45 (18) ◽  
pp. 6341-6348 ◽  
Author(s):  
S. Stoeva ◽  
A. Popov ◽  
R. Rodriguez
Keyword(s):  
Diffraction Study ◽  
Solid Phase ◽  
Wide Angle ◽  
X Ray Diffraction ◽  
X Ray ◽  
Poly Ethylene

Organic Crystals in the Tracheids of Torreya Yunnanensis

IAWA Journal ◽  
1996 ◽  
Vol 17 (4) ◽  
pp. 393-403 ◽  
Author(s):  
Yuki Kondo ◽  
Tomoyuki Fujii ◽  
Yoshioki Hayashi ◽  
Atsushi Kato
Keyword(s):  
Phase Contrast ◽  
Growth Ring ◽  
Uv Spectra ◽  
Resonance Spectroscopy ◽  
Organic Crystals ◽  
X Ray Diffraction ◽  
Cinnamic Aldehyde ◽  
X Ray ◽  
Polarised Light ◽  
Contrast Microscopy

Organic crystals were found in tracheid lumina of some samples of Torreya yunnanensis Chen ' L. K. Fu imported from Yunnan, China. Tracheids with crystals were found in short to long tangential bands along the growth ring boundaries. Because the crystals were rapidly dissolved with ethanol and xylene, cross and tangential sections were mounted in de-ionized water without staining and observed by biological, polarised light, and phase-contrast microscopy. The crystals were sublimated under vacuum during routine sample preparation for conventional SEM and only the peripheral parts remained. With the aid of low vacuum-SEM and modified cryo-SEM procedure, the shape of the crystals was revealed. Some were styloid and large enough to fill tracheid lumina, while others were stacked appearing as slates filling tracheid lumina. X-ray diffraction applied to sections and isolated crystals showed that they were single crystals and orientated along the cell wall. UV spectra on isolated crystals and methanol dissolution of crystals suggested that they were composed of phenolic compounds. Crystals that were recrystallized from methanol were analysed by 1H and l3C nuclear magnetic resonance spectroscopy. These two techniques revealed that the major and minor components were o-methoxy cinnamic acid and o-methoxy cinnamic aldehyde.

Time-resolved isothermal crystallization of absorbable PGA-co-PLA copolymer by synchrotron small-angle X-ray scattering and wide-angle X-ray diffraction

Polymer ◽  
2001 ◽  
Vol 42 (21) ◽  
pp. 8965-8973 ◽  
Author(s):  
Zhi-Gang Wang ◽  
Xuehui Wang ◽  
Benjamin S. Hsiao ◽  
Saša Andjelić ◽  
Dennis Jamiolkowski ◽  
...  
Keyword(s):  
Small Angle ◽  
Isothermal Crystallization ◽  
Wide Angle ◽  
X Ray Diffraction ◽  
Time Resolved ◽  
X Ray ◽  
X Ray Scattering ◽  
Ray Scattering

In situ time resolved wide angle X-ray diffraction study of nanotube carpet growth: Nature of catalyst particles and progressive nanotube alignment

Carbon ◽  
2015 ◽  
Vol 87 ◽  
pp. 246-256 ◽  
Author(s):  
Périne Landois ◽  
Mathieu Pinault ◽  
Stéphan Rouzière ◽  
Dominique Porterat ◽  
Cristian Mocuta ◽  
...  
Keyword(s):  
Diffraction Study ◽  
Wide Angle ◽  
X Ray Diffraction ◽  
Time Resolved ◽  
X Ray

scholarly journals c-Perpendicular Orientation of Poly(ʟ-lactide) Films

Polymers ◽  
2021 ◽  
Vol 13 (10) ◽  
pp. 1572
Author(s):  
Baku Nagendra ◽  
Paola Rizzo ◽  
Christophe Daniel ◽  
Lucia Baldino ◽  
Gaetano Guerra
Keyword(s):  
Low Temperature ◽  
Film Plane ◽  
Wide Angle ◽  
Two Dimensional ◽  
X Ray Diffraction ◽  
Amorphous Films ◽  
High Transparency ◽  
X Ray ◽  
Crystalline Forms ◽  
Induced Crystallization

Poly(ʟ-lactide) (PLLA) films, even of high thickness, exhibiting co-crystalline and crystalline α phases with their chain axes preferentially perpendicular to the film plane (c⊥ orientation) have been obtained. This c⊥ orientation, unprecedented for PLLA films, can be achieved by the crystallization of amorphous films as induced by low-temperature sorption of molecules being suitable as guests of PLLA co-crystalline forms, such as N,N-dimethylformamide, cyclopentanone or 1,3-dioxolane. This kind of orientation is shown and quantified by two-dimensional wide-angle X-ray diffraction (2D-WAXD) patterns, as taken with the X-ray beam parallel to the film plane (EDGE patterns), which present all the hk0 arcs centered on the meridian. PLLA α-form films, as obtained by low-temperature guest-induced crystallization, also exhibit high transparency, being not far from those of the starting amorphous films.

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