Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1996-1-18
pubmed:abstractText
A method is described that allows quantitative determination of polyethylene glycol (PEG) concentrations by spectrophotometric measurement of fluorescein dye absorbance after its partitioning into an aqueous two-phase system containing mPEG (M(r) 5 kDa) in the upper phase and ammonium sulfate in the lower phase. The absorbance decrease of fluorescein in the lower phase is directly proportional to the mPEG concentration, with two proportionality constants equal to 4.42 x 10(5) and 2.84 x 10(5) M-1 cm-1 in the range of 0-0.4 and 0.4-1 microM, respectively. This experimental technique can be extended to PEGs of other molecular weights by means of calibration curves that give for each size of PEG the adequate proportionality constants. The results indicate that the quantitative determination is not affected by the presence of many substances such as proteins, reducing agents, and salts, at the usual concentrations.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0003-2697
pubmed:author
pubmed:issnType
Print
pubmed:day
20
pubmed:volume
230
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
254-8
pubmed:dateRevised
2005-11-17
pubmed:meshHeading
pubmed:year
1995
pubmed:articleTitle
Quantitative determination of polyethylene glycol based upon its salting out and partitioning of a dye into the resulting aqueous two-phase system.
pubmed:affiliation
Protein Chemistry Unit, Faculty of Medicine, University of Brussels, Belgium.
pubmed:publicationType
Journal Article