Development of restricted-access media supports and their application to the direct analysis of biological fluid samples via high-performance liquid chromatography

Abstract

A quick overview of published methods for analyzing compounds in complex biological samples reveals that the most difficult step is the clean-up or extraction of a required compound from the matrix. The strategy required to analyze exogenous compounds in biological fluids depends greatly upon the nature of the compound and upon the biomatrix. Coupled-column separation using restricted-access media as the first dimension in order to exclude macromolecules and retain micromolecules has been successfully used for a number of biological fluids. This paper presents the history of the development of restricted-access media supports and of their application to the direct injection of biological fluid samples in high-performance liquid chromatography.

Targeted determination of the early stage SCLC specific biomarker pro‐gastrin‐releasing peptide (ProGRP) at clinical concentration levels in human serum using LC‐MS

“…3B). These observations led to the application of an online sample clean-up on a RAM column [21] as described in Section 2. As the tryptic digestion step in the sample preparation is performed without prior reduction and alkylation, the resulting sample contains large amounts of incomplete and undigested proteins and peptides.…”

Liquid Chromatography—Its Development and Key Role in Life Science Applications

“…[59] The coupling of GC and MS is the analytical platform for volatile analytes in metabolic analyses. [60] Large differences in abundance and functional group differences require multiple selectivities, which are widely offered by LC. However, the development in metabolomics relies on the improvements in mass spectrometry.…”

“…Reproduced with permission from K.-S. Boos (Laboratorium für BioSeparation, Institut für Klinische Chemie, Klinikum der Universität München). [60] K. K. Unger et al…”

Flüssigkeitschromatographie – ihre Entwicklung und Bedeutung für die Lebenswissenschaften

“…[59] GC-MS-Kopplung ist die analytische Plattform für flüchtige Analyten bei metabolischen Analysen. [60] Hohe Abundanzen und Unterschiede in den funktionellen Gruppen hingegen erfordern viele unterschiedliche Selektivitäten, wie sie von der Flüssigkeitschromatographie bereitgestellt werden.…”

“…Wiedergabe mit Genehmigung von K.-S. Boos (Laboratorium für BioSeparation, Institut für Klinische Chemie, Klinikum der Universität Mün-chen). [60] Flüssigkeitschromatographie Angewandte Chemie wie der MudPit-Ansatz werden immer noch genutzt, obwohl sie keine reproduzierbaren und quantifizierbaren Ergebnisse liefern. [61] Wenngleich eine Reihe von Probenaufarbeitungsmethoden entwickelt und teilweise sogar auf Basis der mehrdimensionalen LC (MD-LC) validiert wurde, ist kein wesentlicher Durchbruch in der Anwendung zu beobachten.…”