Analytical characterization of PEG polymers by MEKC.
Characterization of PEGs with average molecular masses of up to 2000 has been achieved using MEKC with UV detection. A rapid derivatization procedure with phenyl isocyanate using microwave radiation, in order to introduce chromophore groups in PEGs, has been developed involving a reaction time of 60 s. Different optimized conditions in accordance with the molecular weight have been studied to obtain the oligomer separation. The weight-average molecular mass the number-average molecular mass and the degree of polydispersity (molecular mass distribution) were calculated for the different PEGs obtaining similar results with those certified for standards. A good precision was obtained for characterizing the different oligomers. Ethylene glycol was used as the internal standard for the analysis of low-molecular-weight PEGs. The developed method was satisfactorily applied to the characterization of these polymers in several real samples, such as lubricant eye drops, toothpaste, tap water and eye make-up remover.
Plata
María R
MR
Department of Analytical Chemistry and Food Technology, Faculty of Chemistry, University of Castilla-La Mancha, E-13071 Ciudad Real, Spain.
Contento
Ana M
AM
Ríos
Angel
A
D020374:Chromatography, Micellar Electrokinetic Capillary / Q000379:methods*; D005663:Furans / Q000737:chemistry; D016014:Linear Models; D009883:Ophthalmic Solutions / Q000737:chemistry; D011092:Polyethylene Glycols / Q000737:chemistry*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014100:Toothpastes / Q000737:chemistry; D014867:Water / Q000737:chemistry
D005663:Furans; D009883:Ophthalmic Solutions; D014100:Toothpastes; D014867:Water; C018674:tetrahydrofuran; D011092:Polyethylene Glycols