scholarly journals Reciprocal Powered Time model for Release Kinetic Analysis of Ibuprofen Solid Dispersions in Oleaster Powder, Microcrystalline Cellulose and Crospovidone

2010 ◽  
Vol 13 (2) ◽  
pp. 152 ◽  
Author(s):  
Ghobad Mohammadi ◽  
Mohammad Barzegar-Jalali ◽  
Hadi Valizadeh ◽  
Hossein Nazemiyeh ◽  
Azim Barzegar-Jalali ◽  
...  
Keyword(s):  
Particle Size ◽  
Drug Release ◽  
Solid Dispersions ◽  
Release Kinetic ◽  
X Ray Diffraction ◽  
X Ray ◽  
Ft Ir ◽  
Diffraction Patterns ◽  
Release Data ◽  
Dsc Thermograms

ABSTRACT- Purpose. A physically sound derivation for reciprocal power time (RPT) model for kinetic of drug release is given. In order to enhance ibuprofen dissolution, its solid dispersions (SDs) prepared by cogrinding technique using crospovidone (CP), microcrystalline cellulose (MC) and oleaster powder (OP) as a novel carrier and the model applied to the drug release data. Methods. The drug cogrounds with the carriers were prepared and subjected to the dissolution studies. For elucidation of observed in vitro differences, FT-IR spectroscopy, X-ray diffraction patterns, DSC thermograms and laser particle size measurement were conducted. Results. All drug release data fitted very well to newly derived RPT model. The efficiency of the carriers for dissolution enhancement was in the order of: CP>OP>MC. The corresponding release kinetic parameter derived from the model, t50% (time required for 50% dissolution) for the carrier to drug ratio 2:1 were 2.7, 10.2 and 12.6 min, respectively. The efficiency of novel carrier, OP, was between CP and MC. FT-IR showed no interaction between the carriers and drug. The DSC thermograms and X-ray diffraction patterns revealed a slight reduced crystallinty in the SDs. Also grinding reduced mean particle size of drug from 150.7 to 44.4 µm. Conclusion. An improved derivation for RPT model was provided which the parameter of the model, t50%, unlike to previous derivations was related to the most important property of the drug i.e. its solubility. The model described very well drug release kinetics from the solid dispersions. Cogrinding was an effective technique in enhancing dissolution rate of ibuprofen. Elaeagnus angostifolia fruit powder was suggested as a novel potential hydrophilic carrier in preparing solid dispersion of ibuprofen.

Effect of Synthesis Temperature on Particles Size and Morphology of Zirconium Oxide Nanoparticle

2017 ◽  
Vol 50 ◽  
pp. 18-31 ◽  
Author(s):  
Rudzani Sigwadi ◽  
Simon Dhlamini ◽  
Touhami Mokrani ◽  
Patrick Nonjola
Keyword(s):  
Electron Microscopy ◽  
Particle Size ◽  
Zirconium Oxide ◽  
Thermo Gravimetric Analysis ◽  
Gravimetric Analysis ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Crystallite Sizes ◽  
Ft Ir

The paper presents the synthesis and investigation of zirconium oxide (ZrO2) nanoparticles that were synthesised by precipitation method with the effects of the temperatures of reaction on the particles size, morphology, crystallite sizes and stability at high temperature. The reaction temperature effect on the particle size, morphology, crystallite sizes and stabilized a higher temperature (tetragonal and cubic) phases was studied. Thermal decomposition, band structure and functional groups were analyzed by Brunauer-Emmett-Teller (BET), Scanning Electron Microscopy (SEM), Transmission electron microscopy (TEM), X-ray diffraction (XRD), Thermo-gravimetric analysis (TGA) and Fourier transform infrared (FT-IR). The crystal structure was determined using X-ray diffraction. The morphology and the particle size were studied using (SEM) and (TEM). The shaped particles were confirmed through the SEM analysis. The transmission electron microscopic analysis confirmed the formation of the nanoparticles with the particle size. The FT-IR spectra showed the strong presence of ZrO2 nanoparticles.

scholarly journals Understanding the Performance of a Novel Direct Compression Excipient Comprising Roller Compacted Chitin

Marine Drugs ◽  
2020 ◽  
Vol 18 (2) ◽  
pp. 115 ◽  
Author(s):  
Deeb Abu Fara ◽  
Linda Al-Hmoud ◽  
Iyad Rashid ◽  
Babur Z. Chowdhry ◽  
Adnan Badwan
Keyword(s):  
Ball Milling ◽  
Added Value ◽  
Roller Compaction ◽  
Direct Compression ◽  
X Ray Diffraction ◽  
X Ray ◽  
Ft Ir ◽  
Diffraction Patterns ◽  
Hand Drying ◽  
Slight Deformation

Chitin has been investigated in the context of finding new excipients suitable for direct compression, when subjected to roller compaction. Ball milling was concurrently carried out to compare effects from different energy or stress-inducing techniques. Samples of chitin powders (raw, processed, dried and humidified) were compared for variations in morphology, X-ray diffraction patterns, densities, FT-IR, flowability, compressibility and compactibility. Results confirmed the suitability of roller compaction to convert the fluffy powder of raw chitin to a bulky material with improved flow. X-ray powder diffraction studies showed that, in contrast to the high decrease in crystallinity upon ball milling, roller compaction manifested a slight deformation in the crystal lattice. Moreover, the new excipient showed high resistance to compression, due to the high compactibility of the granules formed. This was correlated to the significant extent of plastic deformation compared to the raw and ball milled forms of chitin. On the other hand, drying and humidification of raw and processed materials presented no added value to the compressibility and compactibility of the directly compressed excipient. Finally, compacted chitin showed direct compression similarity with microcrystalline cellulose when formulated with metronidazole (200 mg) without affecting the immediate drug release action of the drug.

scholarly journals Preparation and Properties of Ginger Essential Oil β-Cyclodextrin/Chitosan Inclusion Complexes

Coatings ◽  
2018 ◽  
Vol 8 (9) ◽  
pp. 305 ◽  
Author(s):  
Yan Zhang ◽  
Hui Zhang ◽  
Fang Wang ◽  
Li-Xia Wang
Keyword(s):  
Particle Size ◽  
Essential Oil ◽  
Spray Drying ◽  
Small Particle Size ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Ft Ir ◽  
Thermal Stability Of ◽  
Scanning Electron

The ginger essential oil/β-cyclodextrin (GEO/β-CD) composite, ginger essential oil/β-cyclodextrin/chitosan (GEO/β-CD/CTS) particles and ginger essential oil/β-cyclodextrin/chitosan (GEO/β-CD/CTS) microsphere were prepared with the methods of inclusion, ionic gelation and spray drying. Their properties were studied by using scanning electron microscopy (SEM), differential scanning calorimetry (DSC), thermo-gravimetry analysis (TGA), Fourier transform infrared spectroscopy (FT-IR) and X-ray diffraction (XRD). The results showed that the particle size of GEO/β-CD composite was smaller than that of β-CD and GEO/β-CD/CTS particles were loose and porous, while the microsphere obtained by spray drying had certain cohesiveness and small particle size. Besides, results also indicated that β-CD/CTS could modify properties and improve the thermal stability of GEO, which would improve its application value in food and medical industries.

scholarly journals Construction of a crossed-layer-structure MoS2/g-C3N4 heterojunction with enhanced photocatalytic performance

RSC Advances ◽  
2017 ◽  
Vol 7 (10) ◽  
pp. 6131-6139 ◽  
Author(s):  
Youzhi Cao ◽  
Qiao Li ◽  
Wei Wang
Keyword(s):  
Ir Spectra ◽  
Carbon Nitride ◽  
Photocatalytic Performance ◽  
Layer Structure ◽  
Analytical Techniques ◽  
Graphitic Carbon Nitride ◽  
X Ray Diffraction ◽  
X Ray ◽  
Ft Ir ◽  
Diffraction Patterns

A novel crossed-layer-structure MoS2/g-C3N4 (graphitic carbon nitride) was synthesized by a facile method, and was characterized by a collection of analytical techniques: X-ray diffraction patterns, FT-IR spectra, SEM, TEM, and XPS.

Manufacture of Ternary Solid Dispersions Composed of Nifedipine, Eudragit® E and Adsorbent

2011 ◽  
Vol 317-319 ◽  
pp. 185-188 ◽  
Author(s):  
Pornsak Sriamornsak ◽  
Srisuda Kontong ◽  
Yotsanan Weerapol ◽  
Jurairat Nunthanid ◽  
Srisagul Sungthongjeen ◽  
...  
Keyword(s):  
Dissolution Rate ◽  
Solid Dispersions ◽  
Ternary Systems ◽  
Dissolution Enhancement ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Ternary Solid Dispersions ◽  
Diffraction Patterns ◽  
Physical Mixtures

The aim of this study was to manufacture the ternary solid dispersions composed of nifedipine, Eudragit® E and adsorbent. Dissolution enhancement of nifedipine was also investigated. The inert solid carriers were added in the mixtures of nifedipine and Eudragit® E at varying ratios. The physicochemical properties of ternary systems, compared to physical mixtures, were analyzed using powder x-ray diffraction (PXRD) and differential scanning calorimetry (DSC). The dissolution of nifedipine from ternary systems was compared to the drug alone. The influence of drug:polymer: adsorbent ratio and type of adsorbent on the dissolution rate of the drug was also evaluated. The PXRD and DSC results of the systems with high amount of polymer showed that the drug was present in an amorphous form. On the other hand, the diffraction patterns and DSC thermograms of the physical mixtures revealed that to some extent the drug was present in a crystalline form. The results from this study demonstrated that an improvement in dissolution rate of nifedipine with Eudragit® E and adsorbents was obtained.

Thermal and Structural Characterization of Nanocomposite Iron Nitride - Alumina and Iron Nitride - Silica Particles

2001 ◽  
Vol 703 ◽  
Author(s):  
Ann M. Viano ◽  
Sanjay R. Mishra
Keyword(s):  
Particle Size ◽  
Milling Time ◽  
Iron Nitride ◽  
X Ray Diffraction ◽  
X Ray ◽  
Thermal Peak ◽  
Transmission Electron ◽  
Diffraction Patterns ◽  
The One

ABSTRACTNanocomposite iron nitride based powders are known to have enhanced magnetic and other physical properties. To further explore their potential for application in various fields, we have performed a systematic study of the iron nitride - alumina and iron nitride - silica systems. Iron nitride powder of composition FexN (2 < x < 4), containing both Fe3N and Fe4N phases, was mechanically milled with Al2O3 or SiO2 powder for 4, 8, 16, 32, and 64 hours at the following compositions; (FexN)0.2(Al2O3)0.8, (FexN)0.6(Al2O3)0.4, (FexN)0.2(SiO2)0.8, and (FexN)0.6(SiO2)0.4. Differential thermal analysis and X-ray diffraction were performed to investigate thermal and structural transitions as a function of milling time. As the milling time is increased, the thermal peak corresponding to Fe4N is diminished, while the one corresponding to Fe3N is enhanced. These transitions are correlated with X-ray diffraction patterns. All XRD peaks broaden as a function of milling time, corresponding to smaller particle size. Transmission electron microscopy also reveals a decrease in particle size as the milling time in increased.

scholarly journals THERMAL BEHAVIOR OF PARACETAMOL AND TABLETS OF REFERENCE, GENÉRIC AND SIMILAR

2012 ◽  
Vol 09 (17) ◽  
pp. 28-37
Author(s):  
Francisca Edivânia MORAIS ◽  
Sheila Pricila Marques CABRAL ◽  
Eliane Gonçalves ARAUJO ◽  
Carlos Alberto MARTINEZ-HUITLE ◽  
Nedja Suely FERNANDES
Keyword(s):  
Particle Size ◽  
Thermal Behavior ◽  
Pharmaceutical Formulations ◽  
Endothermic Peak ◽  
X Ray Diffraction ◽  
X Ray ◽  
Thermoanalytical Techniques ◽  
Diffraction Patterns ◽  
Dsc Curves

The present study utilized the thermoanalytical techniques (TG, DTG, DTA and DSC) to evaluate the thermal behavior of tablets containing paracetamol and marketed as reference, generic and similar. The samples were also characterized by IR, X-ray diffraction and SEM. The TG/DTG curves presented similar behaviour indicanting a low influence of the excipients present in pharmaceutical formulations. The DTA and DSC curves showed an endothermic peak between about 165.0 and 195.0 oC characteristic of melting of paracetamol in all samples. The X-ray diffraction patterns showed similarities and characterized the compounds as crystallines. The micrographs indicated heterogeneity in particle size.

scholarly journals Fabrication of bionanocomposite based on LDH using biopolymer of gum arabic and chitosan-coating for sustained drug-release

2020 ◽  
Vol 85 (9) ◽  
pp. 1223-1235 ◽  
Author(s):  
Milad Abniki ◽  
Ali Moghimi ◽  
Fariborz Azizinejad
Keyword(s):  
Drug Release ◽  
Gum Arabic ◽  
X Ray Diffraction ◽  
Sustained Drug Release ◽  
Experimental Conditions ◽  
X Ray ◽  
Model Drug ◽  
Diffraction Patterns ◽  
New Formulation

The study proposed a new formulation to the sustained delivery of mefenamate anions intercalated into Mg?Al layered double hydroxide (LDH) for oral administration. Different experimental conditions were evaluated to incorporate the mefenamic acid (MEF) and gum arabic (GUM) into LDH structure. The LDH?MEF and LDH?MEF/GUM were covered with chitosan (CHIT). In another experiment, LDH?Cl was used to adsorb mefenamate anions and evaluate the mechanism. The products of LDH were characterized by using different techniques such as FESEM (field emission scanning electron microscopy), XRD (X-ray diffraction), FTIR (Fourier transform infrared) spectroscopy and TGA (thermogravimetric analysis). The X-ray diffraction patterns and FTIR analyses confirmed that the MEF and GUM were successfully intercalated into the interlayer space of LDH. TG analysis verified that the thermal stability of intercalated MEF in the form of bionanocomposite (LDH?MEF/ /GUM/CHIT) was enhanced. Finally, In vitro drug release experiments of bionanocomposite at a pH of 1.2 (acidic medium) and a pH of 7.4 (phosphate buffer medium) showed sustained release profiles with mefenamate anions as an anti-inflammatory model drug.

Preparation and Evaluation of Spray Dried Mucoadhesive Microspheres of Metoclopramide Hydrochloride for Nasal Delivery

2013 ◽  
Vol 6 (1) ◽  
pp. 1994-2007
Author(s):  
Galgatte U C ◽  
Kirange R H ◽  
C W Pote ◽  
D A Thanvi ◽  
P D Chaudhari
Keyword(s):  
Particle Size ◽  
Drug Release ◽  
Diffraction Study ◽  
Nasal Delivery ◽  
X Ray Diffraction ◽  
Particle Size Range ◽  
X Ray ◽  
Metoclopramide Hydrochloride ◽  
Carbopol 934P

There is increasing interest in drug delivery through nasal mucosa because of the ability of drug particles to cross membrane due to their particle size in nano or submicron range. The present study was aimed to prepare and evaluate microspheres of metoclopramide hydrochloride (MH) by using HPMC E4M and Carbopol 934P. Microspheres were prepared using spray drying method and particle size was found in the range of 1.62 µm. Drug loaded microspheres of HPMC E4M and Carbopol 934P and combination of HPMC E4M: Carbopol 934P were evaluated for various parameters for optimized batch were drug entrapment (61.73%), mucoadhesive strength (1959.30 g/cms2), and in-vitro diffusion studies (95.61%). Optimized batch also evaluated for SEM, TEM, X-ray diffraction study. Amorphous form of optimized batch was confirmed by X-ray diffraction study. Particles were spherical and discrete confirmed by SEM study. Particle size range was confirmed by TEM. The drug release of optimized batch was carried out by using sheep nasal membrane. Histopathological studies have shown no toxicity to the sheep nasal membrane and hence optimized formulation was found to be safe. The optimized formulation was found to be stable in the accelerated stability studies. It was found that drug entrapment was in the order of HPMC E4M> Carbopol934P > Carbopol 934P: HPMC E4M, mucoadhesive strength Carbopol 934P: HPMC E4M > Carbopol 934P > HPMC E4M, In-vitro drug release Carbopol 934P: HPMC E4M > HPMC E4M > Carbopol 934P. In conclusion, these studies indicate the feasibility and superior pharmacokinetic profile of the metoclopramide nasal system.  

Untersuchungen zum Kristallisationsprozeß in Selenpreßkörpern

1972 ◽  
Vol 27 (7) ◽  
pp. 1124-1126
Author(s):  
J Kispéter ◽  
L Gombay ◽  
J Lang
Keyword(s):  
Particle Size ◽  
Spectral Dependence ◽  
Crystallization Rate ◽  
Trap Depth ◽  
X Ray Diffraction ◽  
Thermally Stimulated Current ◽  
X Ray ◽  
Diffraction Patterns

Abstract The crystallization of compressed selenium was investigated by measurements of the spectral dependence of the photocurrent and of the thermally stimulated current (TSC). A comparison of these results with X-ray diffraction patterns indicates that the maxima of the photocurrent and trap depth calculated from TSC measurements depend on changes in crystallization rate and in-crease in particle size

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