A means of rapid drying of antique wooden material previously saturated with polyethylene glycol (PEG 4000) in a watery solution

1984 ◽  
Vol 13 (4) ◽  
pp. 325-327 ◽  
Author(s):  
Federico Foerster Laures
Keyword(s):  
Polyethylene Glycol ◽  
Peg 4000

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.

Isolation of Antithrombin III Without Interfering with Ethanol Fractionation System

1979 ◽  
Author(s):  
M. Wickerhauser ◽  
C. Williams
Keyword(s):  
Polyethylene Glycol ◽  
Large Scale ◽  
Antithrombin Iii ◽  
Plasma Fraction ◽  
Peg 4000 ◽  
At Iii ◽  
Elution Step ◽  
Final Purification

We described previously the isolation of antithrombin III (AT III) from the 20% polyethylene glycol (PEG 4000) supernatant of plasma or of Cohn Fraction IV-1 (Vox Sang., in press). The first of these two methods gives good recoveries of AT III but cannot be integrated with the conventional ethanol fractionation system due to the presence of PEG in the remaining plasma fraction, while Cohn Fr action IV-1, a byproduct of routine fractionation, is a poor source of AT III in terms of yield. Our modified’method involves batchwise adsorption of AT III from plasma (cryosup-ernatant) with heparin-Sepharose, using one volume of gel for each 50 volumes of plasma. The unadsorbed plasma can be used for ethanol fractionation. The AT III eluate is further purified by precipitation of some impurities including HB Ag, if present, with 20% PEG. Final purification of AT III and removal of PEG is achieved by a second adsorption-elution step on heparin-Sepharose. This method is economical and suitable for large scale application. Recovery of a highly purified AT III was 25%.

Enhancement of Light-induced Nucleation of Lysozyme in the Presence of Polyethylene Glycol (PEG) 4000

2007 ◽  
Vol 36 (2) ◽  
pp. 338-339 ◽  
Author(s):  
Tetsuo Okutsu ◽  
Masaki Sato ◽  
Kenji Furuta ◽  
Yuko Fujinaga ◽  
Kumiko Horota ◽  
...  
Keyword(s):  
Polyethylene Glycol ◽  
Peg 4000

A study on cell surface hydrophobicity, growth and metabolism of Zymomonas mobilis influenced by PEG as a pretreatment agent

RSC Advances ◽  
2015 ◽  
Vol 5 (60) ◽  
pp. 48176-48180
Author(s):  
Niloofar Nasirpour ◽  
Seyyed Mohammad Mousavi ◽  
Seyed Abbas Shojaosadati
Keyword(s):  
Polyethylene Glycol ◽  
Cell Surface ◽  
Zymomonas Mobilis ◽  
Cell Surface Hydrophobicity ◽  
Surface Hydrophobicity ◽  
Ionic Surfactant ◽  
Peg 4000

This study investigates the effects of polyethylene glycol (PEG) 4000, a non-ionic surfactant, on the cell surface hydrophobicity (CSH) ofZymomonas mobilis, as well as its growth and metabolism.

scholarly journals Timed Release of Valsartan from Programmable Release Capsules: Importance of Plasticizers

2013 ◽  
Vol 1 (04) ◽  
pp. 102-107
Author(s):  
Usha Yogendra Nayak ◽  
Gopal Venktesh Shavi
Keyword(s):  
Polyethylene Glycol ◽  
Dibutyl Phthalate ◽  
Dry Weight ◽  
Lag Time ◽  
Polymeric Films ◽  
Mechanical Resistance ◽  
Polyethylene Glycol 4000 ◽  
Peg 4000 ◽  
Triethyl Citrate ◽  
Polyethylene Glycol 6000

The objective of the present study was to evaluate the effect of different plasticizers on the ethylcellulose coatings of capsules and its timed release characteristics. Various plasticizers such as dibutyl phthalate (DBP), triacetin (TA), glycerol, triethyl citrate (TEC), polyethylene glycol-4000 and polyethylene glycol-6000 (PEG) were studied. The physicochemical properties of the casted polymeric films such as mechanical resistance, water uptake and dry weight loss were determined. Also the type and concentration of plasticizer on timed release of the capsule was studied. The drug release was found to be strongly dependent on the type of plasticizer and was in the order of GY>TA>PEG 6000>PEG 4000>TEC>DBP. Capsules coated with hydrophobic DBP (5%) showed good release with a lag time of 6 ± 0.5 h. DBP provided mechanically resistant coatings on the capsule and remained within the polymeric films without leaching upon exposure to the release media which helped in maintaining the lag time.

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 Large Scale Method for the Isolation of Antithrombin III.

1977 ◽  
Author(s):  
M. Wickerhauser ◽  
C. Williams
Keyword(s):  
Polyethylene Glycol ◽  
Hepatitis B ◽  
Gel Electrophoresis ◽  
Large Scale ◽  
Antithrombin Iii ◽  
Scale Method ◽  
Sterile Filtration ◽  
Peg 4000 ◽  
At Iii ◽  
Hepatitis B Antigen

Antithrombin III (AT III) concentrates may be of value in the treatment of various hypercoagulable states associated with congenital or acquired AT III deficiency. We have developed a large scale method for isolation of AT III from plasma or from Cohn fraction IV-1, an unused byproduct of routineplasma fractionation. The method consists of the following steps:(a) precipitation of the starting plasma or Cohn fraction IV-1 extract with 2 0% polyethylene glycol (PEG)4000 to remove a number of impurities including hepatitis B antigen if present;(b) batchwise adsorption to and elution from heparin-Sepharose using one volume of gel for each 50 liters of the 20% PEG supernatant; and (c) concentration of the eluted AT III by bulk lyophilization, followed by desalting on Sephadex G-50, sterile filtration and final lyophilization. In two large scale experiments, 7.1 and 8.7 grams of AT III, determined as antigen by radial immunodiffusion, corresponding to 25,000 and 31,000 plasma equivalents, were recovered from 100 liter plasma and 15 kg Cohn fraction IV-1 batches respectively. Both preparations were over 95% pure by disc gel electrophoresis and had an activity to antigen ratio close to that of AT III in plasma. Both preparations were nonpyrogenic and met all other FDA requirements for biologic products.

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