scholarly journals Salt Cocrystal of Diclofenac Sodium-L-Proline: Structural, Pseudopolymorphism, and Pharmaceutics Performance Study

Pharmaceutics ◽  
2020 ◽  
Vol 12 (7) ◽  
pp. 690 ◽  
Author(s):  
Ilma Nugrahani ◽  
Rizka A. Kumalasari ◽  
Winni N. Auli ◽  
Ayano Horikawa ◽  
Hidehiro Uekusa

Previously, we have reported on a zwitterionic cocrystal of diclofenac acid and L-proline. However, the solubility of this multicomponent crystal was still lower than that of diclofenac sodium salt. Therefore, this study aimed to observe whether a multicomponent crystal could be produced from diclofenac sodium hydrate with the same coformer, L-proline, which was expected to improve the pharmaceutics performance. Methods involved screening, solid phase characterization, structure determination, stability, and in vitro pharmaceutical performance tests. First, a phase diagram screen was carried out to identify the molar ratio of the multicomponent crystal formation. Next, the single crystals were prepared by slow evaporation under two conditions, which yielded two forms: one was a rod-shape and the second was a flat-square form. The characterization by infrared spectroscopy, thermal analysis, and diffractometry confirmed the formation of the new phases. Finally, structural determination using single crystal X-ray diffraction analysis solved the new salt cocrystals as a stable diclofenac–sodium–proline–water (1:1:1:4) named NDPT (natrium diclofenac proline tetrahydrate), and unstable diclofenac–sodium–proline–water (1:1:1:1), named NDPM (natrium diclofenac proline monohydrate). The solubility and dissolution rate of these multicomponent crystals were superior to those of diclofenac sodium alone. The experimental results that this salt cocrystal is suitable for further development.

2009 ◽  
Vol 24 (1) ◽  
pp. 50-57 ◽  
Author(s):  
Chan Woo Kim ◽  
Sung Eun Kim ◽  
Yong Woo Kim ◽  
Hong Jae Lee ◽  
Hyung Woo Choi ◽  
...  

A novel route to organic-inorganic composites was described based on biomineralization of poly(ethylene glycol) (PEG)-based hydrogels. The 3-dimensional hydrogels were synthesized by radical crosslinking polymerization of poly(ethylene glycol fumarate) (PEGF) in the presence of ethylene glycol methacrylate phosphate (EGMP) as an apatite-nuclating monomer, acrylamide (AAm) as a composition-modulating comonomer, and potassium persulfate (PPS) as a radical initiator. We used the urea-mediated solution precipitation technique for biomineralization of hydrogels. The apatite grown on the surface and interior of the hydrogel was similar to biological apatites in the composition and crystalline structure. Powder x-ray diffraction (XRD) showed that the calcium phosphate crystalline platelets on hydrogels are preferentially aligned along the crystallographic c-axis direction. Inductively-coupled plasma mass spectroscopy (ICP-MS) analysis showed that the Ca/P molar ratio of apatites grown on the hydrogel template was found to be 1.60, which is identical to that of natural bones. In vitro cell experiments showed that the cell adhesion/proliferation on the mineralized hydrogel was more pronounced than on the pure polymer hydrogel.


2014 ◽  
Vol 938 ◽  
pp. 40-45 ◽  
Author(s):  
K.N. Porchelvi ◽  
S. Meenakshi ◽  
Kanniyan Pandian

We have synthesized metal phthalocyanine modified multiwalled carbon nanotube by a solid-phase synthesis method by heating a reaction mixture of phthalic anhydride, ammonium molybdate and MWCNT in a required molar ratio using muffle furnace. The metal phthalocyanine modified MWCNT samples collected and then washed extensively with various solvents to removal all impurities and unreacted starting materials. The resulting nanocomposite was characterized by IR, UV-Visible spectroscopy, Scanning Electron Microscopy, X-ray diffraction and Raman spectroscopy. The nanostructure of the CuPc/MWCNT assembly exhibits a homogeneous nanocomposite. The electrocatalytic study of the CuPc/MWCNT assembly towards the oxidation of nitrite was investigated. An enhanced oxidation peak current was noted with lowering oxidation over potential ranges. The proposed method can be applied for the amperometry detection of nitrite present in food samples.


1994 ◽  
Vol 9 (6) ◽  
pp. 1533-1539 ◽  
Author(s):  
S. Goñi ◽  
M.T. Gaztañaga ◽  
J.L. Sagrera ◽  
M.S. Hernández

The influence of NaCl (3% of Cl−by weight of cement) on the reactivity of High Alumina Cement (HAC) in water has been studied over a period of one month. The changes in microstructure were monitored by x-ray diffraction and scanning electron microscopy. The pore-solution, extracted by the application of high mechanical pressure (500 MPa), was studied for the chemical composition and changes caused by chloride and sodium ions.


2009 ◽  
Vol 2009 ◽  
pp. 1-8 ◽  
Author(s):  
Loredana Tammaro ◽  
Giuseppina Russo ◽  
Vittoria Vittoria

Mg-Al Hydrotalcite-like clay (LDH) intercalated with diclofenac anions (HTlc-DIC) was introduced into poly(-caprolactone) (PCL) in different concentrations by the electrospinning technique, and mats of nonwoven fibers were obtained and compared to the pristine pure electrospun PCL. The fibers, characterized by X-ray diffraction, thermogravimetric analysis, and differential scanning calorimetry, show an exfoliated clay structure up to 3 wt%, a good thermal stability of the diclofenac molecules and a crystallinity of PCL comparable to the pure polymer. The scanning electron microscopy revealed electrospun PCL and PCL composite fibers diameters ranging between 500 nm to 3.0 m and a generally uniform thickness along the fibers. As the results suggested the in vitro drug release from the composite fibers is remarkably slower than the release from the corresponding control spun solutions of PCL and diclofenac sodium salt. Thus, HTlc-DIC/PCL fibrous membranes can be used as an antinflammatory scaffold for tissue engineering.


Author(s):  
A Semalty ◽  
M Semalty ◽  
D Singh ◽  
M S M Rawat

Aspirin (acetylsalicylic acid) is one of the most widely used analgesic.  Aspirin is poorly soluble in water and causes gastrointestinal (GI) irritation. To improve the solubility (and hence the bioavailability) and minimize the GI irritation, its complexes with soya-phospholipid-80 % (in  1: 1 molar ratio) were prepared in an organic solvent and evaluated for solubility, drug content, scanning electron microscopy (SEM), FT-IR spectra, X ray diffraction, differential scanning calorimetry (DSC) and in vitro dissolution study. Aspirin-phospholipid complex were found to be disc shaped with rough surface in SEM. Drug content in the complex was found to be 95.6 %. DSC thermograms, XRD and FTIR confirmed the formation of phospholipid complex. Solubility of the prepared complex was found to be improved. Aspirin complex and aspirin showed 90.93 % and 69.42 % of drug release at the end of 10 h in dissolution study in pH 1.2 acid buffer. It was concluded that the phospholipid complex of aspirin may be of potential use for improving the solubility of aspirin and hence its bioavailability. The complexes may also reduce GI toxicity of the drug.  


2013 ◽  
Vol 745-746 ◽  
pp. 21-27
Author(s):  
Cui Ling Du ◽  
Jing Chen ◽  
Bin Bin Cao ◽  
Lei Xu ◽  
Sheng Lu

Micro-arc oxidation (MAO) process was conducted on ZK60 Mg alloy in a basic biologic electrolyte composed of silicate by addition of (NaPO3)6 and NaH2PO4. The microstructural evolution, phase composition and in vitro corrosion resistance of the coating were investigated by means of scanning electron microscopy (SEM) coupled with an energy dispersive spectrometer (EDS) and X-ray diffraction (XRD). The results revealed that bioactive elements Mg, Ca, P and Si were remained in the bio-ceramic coating which can be prepared in suitable biologic electrolyte. For the interaction of (NaPO3)6 and NaH2PO4 , the Ca/P molar ratio of the coating in the optimized biologic electrolyte reached to 1.24 by L9 (34) orthogonal experiments. Compared with the bare ZK60 Mg alloy, the corrosion resistance of the optimized sample in 37 Ringers solution was improved by 4 orders.


MRS Advances ◽  
2017 ◽  
Vol 2 (61) ◽  
pp. 3845-3850
Author(s):  
Jorge López-Cuevas ◽  
Juan C. Rendón-Angeles ◽  
José L. Rodríguez-Galicia ◽  
Carlos A. Gutiérrez-Chavarría

AbstractGlasses and glass-ceramics of the system Diopside [D, CaMgSi2O6] - Fluorapatite [FAp, Ca5(PO4)3F] were synthesized and characterized. The studied theoretical phase compositions were (wt%): 1) 70% D-30% FAp, 2) 60% D-40% FAp and 3) 80% D-20% FAp. The glass-ceramics were synthesized by isothermal treatment of the corresponding parent glasses at either 800, 900 or 1000 °C, with holding times of either 30 min, 2 h or 5 h at high temperature. The in vitro bioactivities of all materials were tested in Kokubo’s Simulated Body Fluid (SBF), for 21 days at pH = 7.4 and 37 °C. All materials were characterized by X-Ray Diffraction (XRD) and Scanning Electron Microscopy (SEM/EDS). In all cases, the in vitro bioactivity increased with decreasing crystallization degree in the materials, which was likely due to an inhibitory effect of the structural changes occurring during thermal treatment of the glasses. This was more accentuated for long thermal treatments. After 21 days of soaking in the SBF, an apatite-like surface layer, with a Ca/P molar ratio close to 1.67, was formed in the case of the parent glass of composition 2. This was attributed to an enhancing effect of so-called “phase separation” phenomenon that took place during the synthesis of that particular glass. Lastly, the MgO content of the glasses made no clear difference on their in vitro bioactivity.


2007 ◽  
Vol 330-332 ◽  
pp. 663-666
Author(s):  
Kun Tian ◽  
Dong Hua Guan ◽  
Ping Wu ◽  
Chun Peng Huang ◽  
Lin Niu ◽  
...  

Based on the molecular recognition theory, an organic molecules model was designed to induce the hydroxyapatite crystallization, to build a tooth-like calcium phosphate/hydroxyapatite under a controllable way in vitro. The cross-linking of collagen on the dentin surface and gelatin was optimized by varying the molar ratio of N,N-(3-dimethylaminopropyl)- N'-ethyl-carbodiimide hydrochloride (EDC) and N-hydroxysuccinimide (NHS) at a constant EDC concentration. CaCl2 and Na3PO4-12H2O solutions were added after the crosslinking process. The whole process requires repeating the crosslinking and mineralization process for five times. The obtained composite were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM) as well as energy dispersive X-ray photoelectron spectroscopy (XPS). The results showed that the dentinal tubule were blocked by neonatal hydroxyapatite layer which has a continuous structure of columns crystal with size of 10-40nm. Furthermore, there was column crystal with parallel direction inside, similar to the crystal array in the top of enamel rod. This study showed that the specific organic molecule model can be used as a potential effective crystal growth modifier.


2009 ◽  
Vol 7 (3) ◽  
pp. 322-327 ◽  
Author(s):  
Lachezar Radev ◽  
Vladimir Hristov ◽  
Irena Michailova ◽  
Bisserka Samuneva

AbstractCeramics, with basic composition based on the CaO-SiO2-P2O5-MgO system with different Ca+ Mg/P+Si molar ratio (R), were prepared via polystep sol-gel technique. The structure of the obtained ceramic materials has been studied by XRD, FTIR spectroscopy, and SEM. X-ray diffraction showed the presence of akermanite and HA for the sample with R = 1.68 and Mg substituted β-TCP and silicocarnotite for the sample with R = 2.16, after thermal treatment at 1200°C/2 h. The obtained results are in good agreement with FTIR. In vitro test for bioactivity in static condition proved that the carbonate containing hydroxyapatite (CO3HA) can be formed on the surface of the synthesized samples. CO3HA consisted of both A- and B-type CO 32− ions. SEM micrographs depicted different forms of HA particles, precipitated on the surface after soaking in 1.5 simulated body fluid (SBF).


2021 ◽  
Author(s):  
Y.Z. Song ◽  
B.X. Qi ◽  
M.T. Li ◽  
J.M. Xie

Abstract Mn0.68Bi0.32OCl mix-crystals for supercapacitor were successfully synthesized via a facile solid-phase method using Bi(NO3)3 and MnCl2 with molar ratio of 1:1 as precursors. The Mn0.68Bi0.32OCl mix-crystals were characterized by scanning electron microscopy, X-ray diffraction, Brunauer-Emmett-Teller surface area measurements and thermogravimetry and differential scanning calorimetry, respectively. Cyclic voltammetry and galvanostatic charge/discharge technique were performed for the Mn0.68Bi0.32OCl mix-crystals in 1 M Na2SO4 aqueous solutions; the specific capacitance of Mn0.68Bi0.32OCl was about 203 F.g-1 at the current density of 3 A. g-1 with a long life time, owing to the high power density of Mn0.68Bi0.32OCl mix-crystals and the higher surface area, good conductivity, and high stability of the Mn0.68Bi0.32OCl mix-crystals.


Sign in / Sign up

Export Citation Format

Share Document