EPA-EAD: 1673: PEG-600 by Derivatization and HPLC
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Official Method Name
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Poly(ethylene glycol)-600 by Derivatization and High-Pressure Liquid Chromatography |
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Current Revision
| Jan-95 |
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Media
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WATER |
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Instrumentation
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High Performance Liquid Chromatography with Ultraviolet Detection |
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Method Subcategory
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Organic |
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Method Source
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Citation
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Brief Method Summary
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One liter of aqueous sample is placed into a liquid-liquid extractor and a known quantity of surrogate is added. Extraction with dichloromethane is carried out over an 18-hour period. The dichloromethane extracts are dried over anhydrous sodium sulfate, evaporated to a small volume and dried again. Remaining dichloromethane is removed and the water-free extract is derivatized using 3,5-dinitrobenzoyl chloride and pyridine in tetrahydrofuran. The tetrahydrofuran solution is diluted with diethyl ether, extracted to remove side products, evaporated, and solvent exchanged with acetonitrile/water and chromatographed on a reverse-phase C18 column with a solvent gradient of 40 percent acetonitrile/water to 100 percent acetonitrile. Detection is performed at 254 nm. The PEG-600 derivative is identified by its retention time relative to that of the derivatized surrogate and quantified by external standard techniques. |
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Scope and Application
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This method is applicable to determining PEG-600 in aqueous samples specific to the pharmaceutical manufacturing industry. |
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Applicable Concentration Range
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Interferences
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(1) Method interferences caused by contaminants in solvents, reagents, glassware, and other sample processing hardware that lead to discrete artifacts and/or elevated baselines in chromatograms. (2) Matrix interferences caused by contaminants coextracted from the sample. |
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Quality Control Requirements
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calibration verification (CV), initial precision and recovery (IPR), reagent blank (RB), ongoing precision and recovery (OPR) |
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Sample Handling
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Grab samples are collected in glass containers having a total volume greater than 1 liter. Fill sample bottles so that no air bubbles pass through the sample. Seal each bottle so that no air bubbles are entrapped. Maintain the hermetic seal on the sample bottles until time of analysis. Samples are maintained at 0 to 4 degrees C from time of collection until analysis. Samples must be extracted within five days of collection, derivatized within seven days of extraction, and analyzed within four days of derivatization. |
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Maximum Holding Time
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5 days (prior to extraction) |
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Relative Cost
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$201 to $400 |
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Sample Preparation Methods
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