Polyethylene glycol chromatography

Measurement by gel permeation chromatography in 0.2 M phosphate buffer pH 7.0 with polystyrenesulfate or polyethylene glycols ([5] in the case of aureobasidium sp. A-91) as molecular weight standards. Data processing as de.scribed in Ref. [II]. 

The purity of the product was checked by vapor phase chromatography on a polyethylene glycol on Teflon column at 72°, 15 p.s.i., and a flow rate of 102 ml. of helium per minute. The sample appeared to be homogeneous, but, since the amine tails badly on the column, it is not possible to detect the presence of a small amount of water (less than 3%). 

Formulated halcinonide, at a concentration of 0.1% in either a cream base or polyethylene glycol-water lotion, after storage at approximately 23° for 3 years, showed no loss on halcinonide content, using high pressure liquid chromatography. 6 The contents remained unchanged within 2% of labeled concentration. 

Pseudoephedrine in urine was analyzed by gas chromatography using a 2% polyethylene glycol 600 + 5% KOH,... 

Does solubility in the mobile phase influence net retention Polyethylene glycols are more soluble in cold solvents than warm. What is the noted effect if the temperature of the liquid chromatography separation of poly ethers is raised ... 

Figure 4.20 Calibration curves for size-exclusion liquid chromatography. Column, TSK GEL G3000SW, 120 cm x 7.5 mm i.d. eluent, 0.2 m sodium phosphate buffer pH 6.8 flow rate, 1.0 ml min-1. Standards 1, protein-, 2, dextran, and 3, polyethylene glycol.

The ethyl acetate solution of organic species from the pre-treatment scheme shown in Figure 1 is suitable for analysis by this method. In order to cover the range of common explosives several chromatography columns with different types of stationary phase are required to allow for difierent polarities and volatihties. Dimethylsiloxane, phenyl-modified dimethylsiloxane, cyanopropyl- phenyl- vinyl-modified dimethylsiloxane, and polyethylene glycol have been found to represent a useful set of stationary phases. Carefully optimised temperature programming is also needed to obtain the requisite resolution and avoid interferences [19, 20]. 

Liu M, Xie C, Xu W, Lu WY. Separation of polyethylene glycols and their amino-substituted derivatives by high-performance gel filtration chromatography at low ionic strength with refractive index detection. Journal of Chromatography A 1046, 121-126, 2004. 

Total ethanol may be determined by gas chromatography using a Stabilwax (polyethylene glycol) column with helium carrier gas under isothermal (35°C) conditions [8], Analyte detection is performed using with a flame ionization detector [8]. The level of ethanol is typically 6 % w/w. 

Liquid samples with low protein concentrations or large amounts of salt should be desalted and concentrated prior to 2-DE. Desalination can be achieved by dialysis or liquid chromatography. The desalted sample is then lyophilized, subject to dialysis against polyethylene glycol or precipitated with acetone to remove interfering compounds. 

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