High through-put Bioanalysis Study through a variety of different Extraction or Desorption Mechanism

Medicilon offers comprehensive and FDA/CFDA GLP-compliant bioanalysis services to support preclinical and clinical development for small molecule drugs, biologics, vaccines and biomarkers.

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Ambient Ionization, or atmospheric pressure ionization, coupled to mass spectrometry techniques have been steadily established themselves as power tools in the analytical toolbox. An important feature of inherent to all ambient ionization is the interfacing of an ion source with a mutually exclusive analyte source. The separation of the sample from the ion source, which can be then be independently optimized, offers a number of great advantages. This leads to another important aspect of ambient ionization techniques, which allows analysis to be performed on a sample in its native, unaltered state with minimal or no sample preparation required. Analytes can be selectively removed from matrix components from the sample for rapid , high through-put bioanalysis study through a variety of different extraction or desorption mechanisms. The hallmark of this area of research is the most mature and well-developed technique, desorption electrospray ionization (DESI) developed by the Cooks group. The number of different applications of DESI is vast ranging from small molecular analysis of drug compounds to imaging applications. It is also a crucial part of the current trend towards miniaturization of MS instrumentation given DESI natural robust and versatile characteristics. DESI has also been applied to a great number of separation techniques, including thin layer chromatography, high pressure liquid chromatography, capillary electrophoresis, and solid phase extraction, to truly create a powerful combinatorial technique in bioanalysis study. The fundamental basis of DESI lies in the generation of electrospray droplets separately from a sample source that is positioned on a sampling stage. The electrospray droplets are aimed towards the sample and then bounced off the sample into the inlet of the MS. As the ESI droplets are passed over the sample and bounced into the MS inlet, analytes of interest are desorbed from the surface of the analyte onto the ESI droplet in a “droplet pick-up” mechanism. As a result of this unique desorption mechanism, target compounds can be rapidly analyzed from native or crude samples with little or no sample preparation required, which upholds the principles of ambient ionization. Another well-established ambient ionization is direct analysis in real time (DART), which can be considered the first demonstration of ambient ionization. DART, like DESI, offers advantages that allow the rapid analysis of compounds directly from native samples despite employing a different ionization mechanism employing a gas stream to generate vapors for detection.