Investigating the Molecular Heterogeneity of Polysorbate Emulsifiers by MALDI-TOF MS

Abstract

Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) is a new technique that can be used to determine the molecular composition of polysorbate emulsifiers, which are commonly used as food additives. This is the first study to offer such a detailed examination of these heterogeneous compounds. MALDI-TOF MS is a powerful tool that can provide a polysorbate mass profile in less than two minutes. 2',4',6'-Trihydroxyacetophenone monohydrate was chosen to be an ideal matrix, as it easily facilitated desorption and ionization, provided good resolution, and allowed for fast and simple preparation of the sample. By addition of aqueous 0.01 M potassium chloride, species were resolved exclusively as potassium adducts in the positive ion mode. MALDI-TOF MS analysis before and after saponification indicated the presence of unbound ethylene oxide polymers, as well as free and esterified sorbitan- and sorbide-based species. Some evidence for the presence of disorbitan-based species was provided. Also illustrated were the polydispersity of the oxyethylene chains, the degree of esterification, and the identity of esterified fatty acids.

Analysis of carbohydrates and glycoconjugates by matrix‐assisted laser desorption/ionization mass spectrometry: An update covering the period 2001–2002

“…DHB has proved to be the best matrix for detection of starch hydrolysate used to adulterate fruit juices (Zídková & Chmelík, 2001). MALDI from THAP with added potassium chloride was used for the first time to study the heterogeneity of polysorbate emulsifiers and produced results in under 2 min (Frison-Norrie & Sporns, 2001). …”

A Quantitative Kinetic Study of Polysorbate Autoxidation: The Role of Unsaturated Fatty Acid Ester Substituents

“…The laurate moiety of PS-20 is a saturated straight chain hydrocarbon, and the oleate moiety of PS-80 is unsaturated, containing a double-bond, resulting in a kink in the hydrocarbon chain. Commercially available polysorbates are generally chemically diverse mixtures of different fatty acid esters (7)(8)(9). While the European Pharmacopoeia specifies the composition of the fatty acid ester substituents for PS-20 and PS-80, as summarized in Table I (10), the United States Pharmacopoeia does not define the percentage of fatty acid esters in polysorbates (10,11).…”

Effect of selected non-ionic surfactants on the flow behavior of aqueous veegum suspensions

“…Another issue that could influence the apparent difference between the performance of the 2 surfactants is that POEbased non-ionic surfactants are known to show heterogeneous composition. 22,23 These results could be critical in the formulation of topical products that include both Veegum and surfactant. For example, montmorillonite clays may be used as an additive in semisolid topical sunscreens.…”