title: Quantitative mass spectrometry imaging of propranolol and olanzapine using tissue extinction calculation as normalization factor.
abstract: In order to quantify small molecules at the early stage of drug discovery, we developed a quantitation approach based on mass spectrometry imaging (MSI) using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) without the use of a labeled compound. We describe a method intended to respond to the main challenges encountered in quantification through MALDI imaging dedicated to whole-body or single heterogeneous organ samples (brain, eye, liver). These include the high dependence of the detected signal on the matrix deposition, the MALDI ionization yield of specific target molecules, and lastly, the ion suppression effect on the tissue. To address these challenges, we based our approach on the use of a normalization factor called the TEC (Tissue Extinction Coefficient). This factor takes into account the ion suppression effect that is both tissue- and drug-specific. Through this protocol, the amount of drug per gram of tissue was determined, which in turn, was compared with other analytical techniques such as Liquid Chromatography-Mass spectrometry (LC-MS/MS).
authors: ImaBiotech, Maldi Imaging Service Department, Parc Eurasanté, Loos, France.
authors: Gregory
authors: G
authors: Hamm
authors: ImaBiotech, Maldi Imaging Service Department, Parc Eurasanté, Loos, France.
authors: David
authors: D
authors: Bonnel
authors: ImaBiotech, Maldi Imaging Service Department, Parc Eurasanté, Loos, France.
authors: Raphael
authors: R
authors: Legouffe
authors: ImaBiotech, Maldi Imaging Service Department, Parc Eurasanté, Loos, France.
authors: Fabien
authors: F
authors: Pamelard
authors: Technologie Servier, Orléans, France.
authors: Jean-Marie
authors: JM
authors: Delbos
authors: Technologie Servier, Orléans, France.
authors: François
authors: F
authors: Bouzom
authors: ImaBiotech, Maldi Imaging Service Department, Parc Eurasanté, Loos, France. Electronic address: Stauber.jonathan@imabiotech.com.
authors: Jonathan
authors: J
authors: Stauber
mesh_terms: D000818:Animals; D000889:Anti-Arrhythmia Agents / Q000032:analysis; D014150:Antipsychotic Agents / Q000032:analysis; D001569:Benzodiazepines / Q000032:analysis*; D003952:Diagnostic Imaging / Q000379:methods / Q000592:standards; D008297:Male; D013058:Mass Spectrometry / Q000379:methods* / Q000592:standards*; D051379:Mice; D008954:Models, Biological; D008962:Models, Theoretical; D000077152:Olanzapine; D011433:Propranolol / Q000032:analysis*; D051381:Rats; D017208:Rats, Wistar; D012015:Reference Standards; D012107:Research Design; D014018:Tissue Distribution
chemical_list: D000889:Anti-Arrhythmia Agents; D014150:Antipsychotic Agents; D001569:Benzodiazepines; D011433:Propranolol; D000077152:Olanzapine