Title of Proposal
Chemical Engineering - Cooperative Education
Bachelor of Science
Date of Graduation
Chemonic™ CCG-6 surfactant is a water-soluble poly(ethylene glycol) (PEG) conjugated alkyl glyceride emollient. This surfactant exists as a complex mixture of a glycerol cores conjugated with poly(ethylene glycol) branches (PEGylation) that were partially esterified with caprylic (C8) and capric (C10) acids. These may be esterified on one, two, or all three arms of the glyceride. The architecture of the structures in this mixture was studied using multidimensional mass spectrometry (MS). Mass spectrometry was interfaced with ultra-performance liquid chromatography (UPLC) and ion mobility (IM) separation. The mixture was separated by reversed-phase LC, oligomers of the star-branched polymer were separated according to their relative polarity, denoted by different retention times. While LC separated according to polarity, IM spectrometry isolated the oligomers of the system by their collision cross-sectional area and charge or size/shape. In either separation method, increasing the fatty acid ester content increased the drift time (DT) or size/shape, and retention time (RT) or polarity. Rudimentary characterization of the mixture identified a range of PEGylated mono-, di-, and triacylglycerides as well as the same moieties attached as acyldiglycerides to a much lesser extent. Over 80% of the compounds are identified as having one or two fatty acid groups, and the overall split of caprylic to capric acids is near 55%/46% C8/C10. The average degree of PEGylation is about 5 units of PEG per molecule type. LC-MS and IM-MS, when used in conjunction, complement each other to separate isobaric species.
Dr. Bi-min Newby
Dr. Chrys Wesdemiotis
Johnson, Charles, "Multidimensional Mass Spectrometry of Chemonic™ CCG-6 Nonionic Surfactant With Separation by Polarity and Shape" (2019). Williams Honors College, Honors Research Projects. 846.