title: Potential of polyE-323 coated capillaries for capillary electrophoresis of lipids.
abstract: In this note the feasibility of a polyamine-based capillary coating, polyE-323, for capillary electrophoresis (CE) of lipids is explored. PolyE-323 has previously been demonstrated to be suitable to suppress analyte-wall interaction of proteins in CE. However, the full applicability range of polyE-323 has not been exploited yet and it might be useful in the analysis of hydrophobic analytes, such as lipids. In this study, the stability of polyE-323 when using highly organic background electrolytes (BGEs), which are needed to solubilize the lipid analytes, was studied. For this, we used three different lipid samples: sphingomyelin, cardiolipin and a lipid extract from a cell culture. The highly organic BGEs that were used in this study consisted of 94.5% of organic solvents and 5.5% of an aqueous buffer. First, the influence of pure acetonitrile, methanol, propylene carbonate, isopropanol and chloroform on the polyE-323 coating was investigated. Then BGEs were developed and tested, using sphingomyelin and cardiolipin as test analytes in CE-UV experiments. After establishing the best BGEs (in terms of analysis time and repeatability) by CE-UV, sphingomyelin was used as a test analyte to demonstrate that method was also suitable for CE with mass-spectrometry detection (CE-MS). The LOD of sphingomyelin was estimated to be 100 nM and its migration time repeatability was 1.3%. The CE-MS analysis was further applied on a lipid extract obtained from human glioblastoma cells, which resulted in the separation and detection of a multitude of putative lipids. The results of our feasibility study indicate that CE systems based on polyE-323 coated capillaries and highly organic BGEs are promising for fast electromigration-based analysis of lipids.
authors.affiliation: Department of Natural Sciences, Institute of Mathematics and Natural Sciences, Tallinn University, Narva mnt. 25, 10120 Tallinn, Estonia.
authors.forename: Kert
authors.initials: K
authors.lastname: Martma
authors.forename: Petrus W
authors.initials: PW
authors.lastname: Lindenburg
authors.forename: Kaia-Liisa
authors.initials: KL
authors.lastname: Habicht
authors.forename: Kaspar
authors.initials: K
authors.lastname: Vulla
authors.forename: Kristiin
authors.initials: K
authors.lastname: Resik
authors.forename: Gunnar
authors.initials: G
authors.lastname: Kuut
authors.forename: Ruth
authors.initials: R
authors.lastname: Shimmo
mesh_terms: D019075:Electrophoresis, Capillary / Q000295:instrumentation* / Q000379:methods; D057230:Limit of Detection; D008055:Lipids / Q000032:analysis* / Q000302:isolation & purification; D009930:Organic Chemicals / Q000737:chemistry; D011073:Polyamines / Q000737:chemistry*; D015203:Reproducibility of Results; D012997:Solvents / Q000737:chemistry
chemical_list: D008055:Lipids; D009930:Organic Chemicals; D011073:Polyamines; D012997:Solvents
keywords: CE; Coating stability; Lipids; Polye-323