Skip to Content
MilliporeSigma
  • Distribution study of atorvastatin and its metabolites in rat tissues using combined information from UHPLC/MS and MALDI-Orbitrap-MS imaging.

Distribution study of atorvastatin and its metabolites in rat tissues using combined information from UHPLC/MS and MALDI-Orbitrap-MS imaging.

Analytical and bioanalytical chemistry (2014-05-21)
Robert Jirásko, Michal Holčapek, Martin Kuneš, Aleš Svatoš
ABSTRACT

The combination of ultrahigh-resolution mass spectrometry imaging (UHRMSI) and ultrahigh-performance liquid chromatography coupled with tandem mass spectrometry (UHPLC/MS/MS) was used for the identification and the spatial localization of atorvastatin (AT) and its metabolites in rat tissues. Ultrahigh-resolution and high mass accuracy measurements on a matrix-assisted laser desorption/ionization (MALDI)-Orbitrap mass spectrometer allowed better detection of desired analytes in the background of matrix and endogenous compounds. Tandem mass spectra were also used to confirm the identification of detected metabolites in complex matrices. The optimization of sample preparation before imaging experiments included the tissue cryogenic sectioning (thickness 20 μm), the transfer to stainless steel or glass slide, and the selection of suitable matrix and its homogenous deposition on the tissue slice. Thirteen matrices typically used for small molecule analysis, e.g., 2,5-dihydroxybenzoic acid (DHB), 1,5-diaminonaphthalene (DAN), 9-aminoacridine (AA), etc., were investigated for the studied drug and its metabolite detection efficiency in both polarity modes. Particular matrices were scored based on the strength of extracted ion current (EIC), relative ratio of AT molecular adducts, and fragment ions. The matrix deposition on the tissue for the most suitable matrices was done by sublimation to obtain the small crystal size and to avoid local variations in the ionization efficiency. UHPLC/MS profiling of drug metabolites in adjacent tissue slices with the previously optimized extraction was performed in parallel to mass spectrometry imaging (MSI) measurements to obtain more detailed information on metabolites in addition to the spatial information from MSI. The quantitation of atorvastatin in rat liver, serum, and feces was also performed.

MATERIALS
Product Number
Brand
Product Description

Sigma-Aldrich
Methanol, HPLC Plus, ≥99.9%, poly-coated bottles
Supelco
9-Aminoacridine, matrix substance for MALDI-MS, ≥99.5% (HPLC)
Sigma-Aldrich
Acetonitrile solution, contains 0.05 % (v/v) trifluoroacetic acid
Sigma-Aldrich
Methanol, NMR reference standard
Supelco
Butylamine, analytical standard
Sigma-Aldrich
Methanol, ACS reagent, ≥99.8%
Sigma-Aldrich
Methanol, suitable for HPLC, gradient grade, ≥99.9%
Sigma-Aldrich
Methanol, suitable for HPLC, gradient grade, suitable as ACS-grade LC reagent, ≥99.9%
Sigma-Aldrich
Methanol, puriss., meets analytical specification of Ph Eur, ≥99.7% (GC)
Sigma-Aldrich
Methanol, puriss. p.a., ACS reagent, reag. ISO, reag. Ph. Eur., ≥99.8% (GC)
Supelco
Residual Solvent - Acetonitrile(solution in DMSO), Pharmaceutical Secondary Standard; Certified Reference Material
Sigma-Aldrich
Methanol, anhydrous, 99.8%
Sigma-Aldrich
Butylamine, ≥99%
Sigma-Aldrich
3-Aminoquinoline, 98%
Sigma-Aldrich
Methanol, suitable for HPLC, gradient grade, 99.93%
Sigma-Aldrich
N,N,N′,N′-Tetramethyl-1,8-naphthalenediamine, purum, ≥99.0% (NT)
Sigma-Aldrich
Aminopyrazine, 98%
Sigma-Aldrich
Ammonium acetate, BioXtra, ≥98%
Sigma-Aldrich
Ammonium acetate solution, for molecular biology, 7.5 M
Sigma-Aldrich
Ammonium acetate, reagent grade, ≥98%
Sigma-Aldrich
Ammonium acetate, for molecular biology, ≥98%
Sigma-Aldrich
Ammonium acetate solution, 50 % (w/v)
Sigma-Aldrich
Methanol, JIS 300, ≥99.8%, for residue analysis
Sigma-Aldrich
Methanol, JIS special grade, ≥99.8%
Sigma-Aldrich
Acetic acid-12C2, 99.9 atom % 12C
Sigma-Aldrich
Methanol, SAJ first grade, ≥99.5%
Sigma-Aldrich
Methanol, SAJ special grade
Sigma-Aldrich
Butylamine, 99.5%
Sigma-Aldrich
Acetonitrile solution, contains 10.0% acetone, 0.05% formic acid, 40.0% 2-propanol
Supelco
Methanol, analytical standard