Analysis of oxysterols and vitamin D metabolites in mouse brain and cell line samples by ultra-high-performance liquid chromatography-atmospheric pressure photoionization-mass spectrometry.

Analysis of oxysterols and vitamin D metabolites in mouse brain and cell line samples by ultra-high-performance liquid chromatography-atmospheric pressure photoionization-mass spectrometry.

Journal of chromatography. A (2014-09-11)

Linda Ahonen, Florian B R Maire, Mari Savolainen, Jaakko Kopra, Rob J Vreeken, Thomas Hankemeier, Timo Myöhänen, Petri Kylli, Risto Kostiainen

PMID25204266

ABSTRACT

We have developed an ultra-high-performance liquid chromatography-atmospheric pressure photoionization-tandem mass spectrometric (UHPLC-APPI-MS/MS) method for the simultaneous quantitative analyses of several oxysterols and vitamin D metabolites in mouse brain and cell line samples. An UHPLC-APPI-high resolution mass spectrometric (UHPLC-APPI-HRMS) method that uses a quadrupole-time of flight mass spectrometer was also developed for confirmatory analysis and for the identification of non-targeted oxysterols. Both methods showed good quantitative performance. Furthermore, APPI provides high ionization efficiency for determining oxysterols and vitamin D related compounds without the time consuming derivatization step needed in the conventionally used electrospray ionization method to achieve acceptable sensitivity. Several oxysterols were quantified in mouse brain and cell line samples. Additionally, 25-hydroxyvitamin D3 was detected in mouse brain samples for the first time.

MATERIALS

Product Number

Brand

Product Description

632546

Supelco

Methanol solution, contains 0.10 % (v/v) formic acid, UHPLC, suitable for mass spectrometry (MS), ≥99.5%

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USP

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USP

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Vitamin D2 solution, 1 mg/mL in ethanol, ampule of 1 mL, certified reference material, Cerilliant^®

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Methanol, HPLC Plus, ≥99.9%, poly-coated bottles

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