scholarly journals The Influence of Temperature and Viscosity of Polyethylene Glycol on the Rate of Microwave-Induced In Situ Amorphization of Celecoxib

Molecules ◽  
2020 ◽  
Vol 26 (1) ◽  
pp. 110
Author(s):  
Nele-Johanna Hempel ◽  
Tra Dao ◽  
Matthias M. Knopp ◽  
Ragna Berthelsen ◽  
Korbinian Löbmann
Keyword(s):  
Polyethylene Glycol ◽  
Microwave Radiation ◽  
Magnesium Stearate ◽  
Einstein Equations ◽  
Dissolution Process ◽  
Target Temperature ◽  
Peg 4000 ◽  
Lower Viscosity ◽  
Model Drug

Microwaved-induced in situ amorphization of a drug in a polymer has been suggested to follow a dissolution process, with the drug dissolving into the mobile polymer at temperatures above the glass transition temperature (Tg) of the polymer. Thus, based on the Noyes–Whitney and the Stoke–Einstein equations, the temperature and the viscosity are expected to directly impact the rate and degree of drug amorphization. By investigating two different viscosity grades of polyethylene glycol (PEG), i.e., PEG 3000 and PEG 4000, and controlling the temperature of the microwave oven, it was possible to study the influence of both, temperature and viscosity, on the in situ amorphization of the model drug celecoxib (CCX) during exposure to microwave radiation. In this study, compacts containing 30 wt% CCX, 69 wt% PEG 3000 or PEG 4000 and 1 wt% lubricant (magnesium stearate) were exposed to microwave radiation at (i) a target temperature, or (ii) a target viscosity. It was found that at the target temperature, compacts containing PEG 3000 displayed a faster rate of amorphization as compared to compacts containing PEG 4000, due to the lower viscosity of PEG 3000 compared to PEG 4000. Furthermore, at the target viscosity, which was achieved by setting different temperatures for compacts containing PEG 3000 and PEG 4000, respectively, the compacts containing PEG 3000 displayed a slower rate of amorphization, due to a lower target temperature, than compacts containing PEG 4000. In conclusion, with lower viscosity of the polymer, at temperatures above its Tg, and with higher temperatures, both increasing the diffusion coefficient of the drug into the polymer, the rate of amorphization was increased allowing a faster in situ amorphization during exposure to microwave radiation. Hereby, the theory that the microwave-induced in situ amorphization process can be described as a dissolution process of the drug into the polymer, at temperatures above the Tg, is further strengthened.

scholarly journals EVALUATING THE BEST POLYETHYLENE GLYCOL AS SOLID DISPERSION CARRIER BY TAKING ETORICOXIB AS A MODEL DRUG

2019 ◽  
pp. 250-255
Author(s):  
HEMANTH A ◽  
HINDUSTAN ABDUL AHAD ◽  
DEVANNA N
Keyword(s):  
Polyethylene Glycol ◽  
Solid Dispersion ◽  
Solid Dispersions ◽  
Physicochemical Characteristics ◽  
Peg 6000 ◽  
Good Solubility ◽  
Peg 4000 ◽  
Tablet Compression ◽  
Model Drug ◽  
Peg 8000

Objective: The main objective of the current research is focused in discovering the best polyethylene glycol (PEG) as solid dispersion carrier using etoricoxib (ECB) as a model drug. Methods: Varieties of PEG, namely PEG - 3350, PEG - 4000, PEG - 6000, PEG - 8000, and PEG - 20000, were evaluated as a carrier for making ECB solid dispersions. ECB:PEG was taken in the ratios of 1:1, 1:2, 1:4, and 1:6. The solid dispersions were prepared by microwave fusion method and compressed using 8 station tablet compression machine. The fabricated solid dispersion tablets were tested for physicochemical characteristics and drug release rates. The release of ECB from the prepared solid dispersions was further analyzed kinetically using the first order and Hixson-Crowell’s plots. Results: All the solid dispersion batches were shown satisfactory physicochemical characteristics. ECB solid dispersion batches with PEG - 6000 showed good solubility in distilled water (up to 2.29±0.01 μg/ml) and in 0.1 N HCl (up to 2.18±0.01 μg/ml) when compared with ECB alone (0.21±0.01 μg/ml and 0.32±0.01 μg/ml). The prepared solid dispersions with PEG 6000 are shown good ECB release. Conclusion: Among PEG carriers, PEG - 6000 was found to be the best carrier for increasing the solubility and release rate of ECB form the solid dispersions compared to PEG - 3350, PEG - 4000, PEG - 8000, and PEG - 20000.

scholarly journals Studying the Impact of the Temperature and Sorbed Water during Microwave-Induced In Situ Amorphization: A Case Study of Celecoxib and Polyvinylpyrrolidone

Pharmaceutics ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 886
Author(s):  
Nele-Johanna Hempel ◽  
Matthias M. Knopp ◽  
Korbinian Löbmann ◽  
Ragna Berthelsen
Keyword(s):  
Microwave Radiation ◽  
Linear Correlation ◽  
Amorphous Solid ◽  
Magnesium Stearate ◽  
Model Systems ◽  
Drug Dissolution ◽  
Amorphous Solid Dispersion ◽  
Sorbed Water ◽  
The Impact

Microwave-induced in situ amorphization of a drug into a polymeric amorphous solid dispersion (ASD) has been suggested to follow a dissolution process of the drug into the polymeric network, at temperatures above the glass transition temperature (Tg) of the polymer. Thus, increasing the compact temperature, above the Tg of the polymer, is expected to increase the rate of drug dissolution in the mobile polymer, i.e., the rate of amorphization, in a direct proportional fashion. To test this hypothesis, the present study aimed at establishing a linear correlation between the compact temperature and the rate of drug amorphization using celecoxib (CCX) and the polymers polyvinylpyrrolidone (PVP) 12 and PVP17 as the model systems. Water sorbed into the drug–polymer compacts during 2 weeks of storage at 75% relative humidity was used as the dielectric heating source for the present drug amorphization process, and therefore directly affected the compact temperature during exposure to microwave radiation; the loss of water during heating was also studied. For this, compacts prepared with 30 wt% CCX, 69.5 wt% PVP12 or PVP17 and 0.5 wt% magnesium stearate (lubricant) were conditioned to have a final water content of approx. 20 wt%. The conditioned compacts were exposed to microwave radiation for 10 min at variable power outputs to achieve different compact temperatures. For compacts containing CCX in both PVP12 and PVP17, a linear correlation was established between the measured compact end temperature and the rate of drug amorphization during 10 min of exposure to microwave radiation. For compacts containing CCX in PVP12, a fully amorphous ASD was obtained after 10 min of exposure to microwave radiation with a measured compact end temperature of 71 °C. For compacts containing CCX in PVP17, it was not possible to obtain a fully amorphous ASD. The reason for this is most likely that a fast evaporation of the sorbed water increased the Tg of the conditioned drug–polymer compacts to temperatures above the highest reachable compact temperature during exposure to microwave radiation in the utilized experimental setup. Supporting this conclusion, evaporation of the sorbed water was observed to be faster for compacts containing PVP17 compared to compacts containing PVP12.

Impact of Chain Length on Release Behavior of Modified Polyethylene Glycol Intercalated-Montmorillonite Nanocomposite

2020 ◽  
Vol 20 (9) ◽  
pp. 5546-5554
Author(s):  
Mosaed Al-Sahly ◽  
Hany El-Hamshary ◽  
Salem S. Al-Deyab
Keyword(s):  
Electron Microscopy ◽  
Polyethylene Glycol ◽  
Ion Exchange ◽  
Chain Length ◽  
Fickian Diffusion ◽  
Release Behavior ◽  
Molecular Weights ◽  
Peg 4000 ◽  
Model Drug ◽  
Peg Chain Length

A new drug delivery nanocomposite system was prepared from sodium montmorillonite (Na+Mt) intercalated with modified polyethylene glycol (PEG). PEGs of different molecular weights (400, 4000, and 8000) were modified with glycidyltrimethylammonium chloride (GTMAC) to provide terminal quaternary ammonium sites capable for attaching with Mt or other materials through ion exchange. The modified PEG-GTMAC derivatives were reacted in excess amount with Na+Mt through ion exchange. The remaining quaternary sites were used for the attachment of sodium diclofenac as a model drug. The structures of the prepared clay-modified PEG-diclofenac systems were characterized using Fourier transform infrared spectroscopy (FTIR), powder X-ray diffraction (PXRD), transmission electron microscopy (TEM), and scanning electron microscopy (SEM). The release behavior of diclofenac from the different nanocomposites was studied at different pH values. With regard to the PEG chain length, the drug release increased with increasing PEG molecular weight (GCDIII > GCD-III > GCDII > GCDI). The kinetics of the release models was discussed using Korsmeyer–Peppas, Higuchi, and zero- and first-order models. The results of the kinetics study revealed that modified samples with PEG 400 and PEG 4000 (GCD-I and GCDII) exhibited non-Fickian diffusion (anomalous transport) while modified samples with PEG 8000 (GCDIII) exhibited super case-II transport.

Thermal gravimetric analysis of in-situ crosslinked nanocellulose whiskers • poly(methyl vinyl ether-co-maleic acid) • polyethylene glycol

TAPPI Journal ◽  
2011 ◽  
Vol 10 (4) ◽  
pp. 29-33
Author(s):  
LEE A. GOETZ ◽  
AJI P. MATHEW ◽  
KRISTIINA OKSMAN ◽  
ARTHUR J. RAGAUSKAS
Keyword(s):  
Thermal Stability ◽  
Polyethylene Glycol ◽  
Vinyl Ether ◽  
Thermal Gravimetric Analysis ◽  
Maleic Acid ◽  
Gravimetric Analysis ◽  
Thermal Gravimetric ◽  
Methyl Vinyl ◽  
Methyl Vinyl Ether

The thermal stability and decomposition of in-situ crosslinked nanocellulose whiskers – poly(methyl vinyl ether-co-maleic acid) – polyethylene glycol formulations (PMVEMA-PEG), (25%, 50%, and 75% whiskers) – were investigated using thermal gravimetric analysis (TGA) methods. The thermal degradation behavior of the films varied according to the percent cellulose whiskers in each formulation. The presence of cellulose whiskers increased the thermal stability of the PMVEMA-PEG matrix.

scholarly journals Microwave-induced in situ drug amorphization using a mixture of polyethylene glycol and polyvinylpyrrolidone

2021 ◽  
Author(s):  
Nele-Johanna Hempel ◽  
Matthias M. Knopp ◽  
J. Axel Zeitler ◽  
Ragna Berthelsen ◽  
Korbinian Löbmann
Keyword(s):  
Polyethylene Glycol

An in situ Raman spectroscopic method for quantification of polyethylene glycol (PEG) in waterlogged archaeological wood

Holzforschung ◽  
2020 ◽  
Vol 74 (11) ◽  
pp. 1043-1051
Author(s):  
Åke Henrik-Klemens ◽  
Katarina Abrahamsson ◽  
Charlotte Björdal ◽  
Alexandra Walsh
Keyword(s):  
Polyethylene Glycol ◽  
Spectroscopic Method ◽  
Calibration Model ◽  
Efficient Treatment ◽  
Raman Spectroscopic ◽  
Archaeological Wood ◽  
Validation Set ◽  
Impregnation Period ◽  
Polymer Impregnation

AbstractThe weakened microstructure of archaeological wood (AW) objects from waterlogged environments necessitates consolidation to avoid anisotropic shrinkage upon drying. Polymer impregnation through submergence or spraying treatments is commonly applied, and for larger and thicker objects, the impregnation period can stretch over decades. Thus, for efficient treatment, continuous monitoring of the impregnation status is required. Today, such monitoring is often destructive and expensive, requiring segments for extraction and chromatographic quantification. This study proposes an in situ Raman spectroscopic method for quantification of polyethylene glycol (PEG) in waterlogged AW. A calibration model was built on standards of PEG, cellulose powder, and milled wood lignin using orthogonal partial least squares (OPLS). The OPLS model had a strong linear relationship, and the PEG content in wood of varying degrees of degradation could be determined. However, the accuracy of the model was low with a root mean square error of prediction of 11 wt%. The low accuracy was traced to the heterogeneity in the calibration and validation set samples with regard to the small probing volume of the confocal instrumental setup.

Effect of Annealing Conditions on the Dissolution Process of Complex Carbonitrides in a V-Nb-Ti Microalloyed Steel

2018 ◽  
Vol 941 ◽  
pp. 21-26
Author(s):  
Gloria Basanta ◽  
Ana L. Rivas ◽  
Ervis Díaz ◽  
Carlos Parra
Keyword(s):  
Inductively Coupled Plasma ◽  
Microalloyed Steel ◽  
Optical Emission ◽  
Dissolution Process ◽  
Emission Spectrometry ◽  
Inductively Coupled ◽  
Annealing Conditions ◽  
Plasma Optical Emission Spectrometry

The present work has been undertaken to assess the evolution of dissolution process of large dendritic precipitates in a V-Nb-Ti microalloyed steel. The study was performed by reheating the samples at 1250°C, simulating the industrial reheating practices at laboratory scale and in situ, following industrial profile; afterwards the samples were quenched in 10%NaCl aqueous solution. The characterization of the material was carried out by scanning electron microscopy accompanied with dispersive energy spectrometry, and chemical analysis by inductively coupled plasma optical emission spectrometry. The results showed a partial dissolution of dendritic precipitates. This process ocurred by a progressive dissolving the Nb-rich shells formed over cuboidal particles and primary arm of well-faceted dendritic precipitates, and by fragmentation and spheroidization of secondary branches. These processes gave rise to spherical Nb rich precipitates and cuboidal particles at the reheating conditions used in this study. Both type of particles contain vanadium.

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