Eberhard Karls University, Institute of Pharmaceutical Sciences, Tübingen, Germany

 

Q: WHAT IS THE FOCUS OF YOUR LAB’S RESEARCH?

A: We are a Medicinal Chemistry laboratory with a major focus on kinase inhibitors. Within the last decade, we have developed highly potent and selective chemical probes such as Skepinone L, a specific p38 MAP kinase inhibitor suitable for in vivo use. Our strategies involve the reversible targeting of kinases via ATP-competitive type I or less competitive type II inhibitors as well as intermediate type 11/2 inhibitors. More recently, we turned towards covalent kinase targeting by addressing non-catalytic cysteines. This strategy furnished excellent probes for JNK3 and JAK3. For example, we developed FM-381, an extremely isoform-selective JAK3 inhibitor, which is now available as a high-quality probe from the Chemical Probes Portal and the chemical probes program of the Structural Genomics Consortium.

Q: WHAT WAS YOUR PREVIOUS WORK EXPERIENCE?

A: Since our work mainly relies on organic synthesis, we have an urgent need for accurate and rapid characterization of novel compounds. While our group owns two NMR spectrometers and several HPLC systems, mass spectrometry was usually done at a shared service unit, which caused additional costs and delays. Although we were also equipped with several LC-MS devices, these were routinely used for biological samples or metabolism studies, thus adapting the workflows for chemical samples was always tedious. Consequently, a more practical solution was required.

Q: WHY DID YOU INCORPORATE THE EXPRESSION CMS INTO YOUR LABORATORY?

A: As mentioned, mass spectrometry was one of the bottlenecks in our synthesis endeavors. The purchase of an LC-MS system exclusively for reaction monitoring and compound analysis would have been an option. However, especially when dealing with crude mixtures, LC-MS devices are typically quite vulnerable and require a lot of maintenance. Moreover, if you do not have a UPLC system, LC-MS runs are time-consuming, limiting the number of samples to a maximum of a few dozens a day, which is a serious problem with respect to the size of our group.

Therefore, Advion’s expression CMS in combination with the Plate Express™ TLC plate reader was the perfect solution for us. It is easy to use, quite robust, offers a high throughput, and is suitable for almost the entire mass range of our compounds. Needless to say, the device is especially suited for reaction monitoring and the rapid assignment of product fractions from column chromatography.

Q: TO WHOM WOULD YOU RECOMMEND THE EXPRESSION CMS?

A: The expression CMS/Plate Express™ couple can be recommended to Organic or Medicinal Chemistry groups in general since it seamlessly integrates into organic synthesis workflows. Due to the affordable pricing, it is also a great solution for chemists in academia. Especially laboratories with high turnover of masters students and research interns will appreciate the robustness of the system.

Toluene-Assisted APCI and Elemental Composition Prediction Using a Compact Mass Spectrometer

OVERVIEW

  • Toluene-assisted APCI (TAPCI) can generate (M)+· and (M+H)+ ions from analytes that cannot be ionized by ESI or APCI.
  • Elemental formula prediction at 250 ppm accuracy and isotope distribution matching by TAMI (Tal Aviv Molecule Identifier) supports analyte identification.
  • Combining both TAPCI and TAMI on the expression compact mass spectrometer (CMS) provides a cost-effective analysis platform for a wide range of compounds.

INTRODUCTION

Many compounds in organic synthetic chemistry either have no functional group, a C=O carbonyl group, or protected functional groups and are difficult to ionize by ESI or APCI for detection by mass spectrometry. TAPCI has been shown to ionize compounds to (M)+· and (M+H)+ protonated molecules not accessible by ESI or APCI MS analysis. The ionization is believed to include a charge transfer reaction in the APCI plasma region of the source. Elemental formula prediction using TAMI allows analyte identification on a single quadrupole mass spectrometer with mass accuracy in the 250 ppm range, isotope pattern analysis and auto comparison to NIST databases. Here, we investigate the use of both techniques on the expression CMS as an attractive and cost-effective solution for analyte identification covering an increased compound space.

Rapid Screening for Fentanyl in Urine using the Advion Interchim Scientific expressionL CMS with the Touch Express™ Open Port Sampling Interface (OPSI)

Quick and easy analysis methods for drugs of abuse are in high demand from health practitioners and law enforcement agencies on a global scale. In 2017, it was found that fentanyl, a fast-acting synthetic painkiller that is nearly 100 times stronger than morphine, has become the most widely abused synthetic opioid medicine – to the point it has become a public health problem. In this application note, a simple method for fentanyl screening in urine is introduced, using Advion Interchim Scientific’s Touch Express™ Open Port Sampling Interface (OPSI) coupled with the expressionL Compact Mass Spectrometer (CMS).

OPSI was developed by Gary Van Berkel and Vilnos Kertesz of Oak Ridge National Laboratory. Paired with the electrospray ionization (ESI) source of the CMS, Touch Express™ OPSI offers a fast assay benchtop solution in a small-footprint, easy-to-use system.

Urinary Cortisol Quantitation Using Ultra High Pressure Liquid Chromatography/Compact Mass Spectrometry

Introduction

Cortisol is an important steroid hormone produced from cholesterol in the adrenal cortex. Its secretion is closely regulated by Adrenocorticotropic hormone (ACTH). Most cortisol is protein-bound, and only unbound cortisol is excreted in urine. Measurement of cortisol in urine is typically used in the diagnosis of Cushing’s syndrome, a disorder of hypercortisolism.

Although immunoassay methods have extremely high sensitivity, they are subject to variable interferences from other steroids and their conjugates. Liquid chromatography with tandem mass spectrometry is increasingly used in clinical analysis because of its higher specificity and selectivity than immunoassay methods. A simple and robust UHPLC/MS method will be introduced for urinary cortisol analysis and the dynamic range and sensitivity (LOD and LLOQ) of the UHPLC/CMS method will be evaluated.

Rapid Screening for Fentanyl in Urine Using a Compact Mass Spectrometer (CMS) with an Open Port Sampling Interface (OPSI)

Introduction

Fentanyl, a fast-acting synthetic painkiller about 100 times stronger than morphine, is also the most widely used synthetic opioid medicine in 2017.1 Its abuse is becoming a public health problem. A quick and easy analysis method for this drug is in high demand from health practitioners and law enforcement agencies.

The Touch Express™ Open Port Sampling Interface (OPSI),2,3 is designed for simple sampling of solids, liquids, sample preparation tips and fibers. Paired with the ESI of the expression® CMS, the product incorporates an open port of continuous low-volume solvent, flowing directly into the ESI for MS analysis. Any soluble sample touching the open port will be analyzed by the mass spectrometer in just seconds.

Here, a simple and quick analysis method for fentanyl in urine using Touch Express™ OPSI on the Advion expression® CMS is presented.

Cannabis-related Bioanalysis (from Plant to Forensic) using LC-CMS (Single Quad)

Introduction

The legalization of marijuana and hemp provides commercial opportunities as well as analytical challenges. Accurate and precise quantitative analysis of plant and medicinal products is needed in this new industry to document composition and assure the safety of cannabis products. LC/MS techniques can provide unparalleled selective and sensitive measurements for these purposes. Here we describe the use of a relatively inexpensive compact mass spectrometer for SIM LC/MS analysis of cannabis-related applications.

This poster was presented at ASMS 2018 Annual Conference in San Diego, CA.

Toluene-Assisted APCI Using a Compact Mass Spectrometer

Overview

  • Toluene-assisted APCI (TAPCI) can generate (M)+· and (M+H)+ molecules from analytes not MS accessible by ESI or APCI.
  • Elemental formula prediction at 250 ppm accuracy and isotope distribution matching by TAMI (Tal Aviv Molecule Identifier) supports analyte identification.
  • Combining both TAPCI and TAMI on a compact single quadrupole mass spectrometer (CMS) provides a cost-effective analysis platform for a wide compound space.

Monitoring Synthetic Reactions Using an (inert) Atmospheric Solids Analysis Probe (iASAP)

Introduction

Metal based compounds have found utility in various fields such as clinical, energy, food safety and environmental to name a few. Creating the metal complex is the last step in a synthetic process when ligands are bound to the metal center. Once made, these metal complexes can be used anywhere from stereospecific synthesis to anti-cancer drugs. It is critical that reaction conditions are providing the desired product and that side products are kept to a minimum to maximize yield. Presented here is the use of an inert atmospheric solid analysis (iASAP) probe to quickly sample and measure the reaction via mass spectrometry.

University of Leeds Webinar: Self-Optimizing Continuous Flow Reactors

Chemical processes can be performed in two ways; in batch or in flow, each method having set advantages and disadvantages associated with them.

Flow chemistry has gathered increasing attention over the past decade and is being readily adopted into academia to help improve synthetic routes, which maybe undesirable in batch, where outputs such as yield, productivity, E-factor or selectivity maybe improved via various methods of optimisation. On-line analytics within continuous flow chemistry allow reactions to be monitored in real-time ultimately allowing immediate characterisation and the ability to optimise in the easiest possible way.

Hosted by Jack Henion, Advion’s Chief Scientific Founder, Chris Horbaczewskyj of the University of Leeds outlines the work carried out within the Bourne group for process development applications:

  • Use of flow chemistry with online HPLC in the self-optimisation of reactions,
  • Use of online mass spectrometry for the optimisation of continuous flow reactions using an experimental design approach,
  • The development of new algorithms for multiple variable optimisation in chemical systems.

LC/CMS Determination of Polycyclic Aromatic Hydrocarbons (PAHS) in Water (EPA 610 Mix)

Polycyclic aromatic hydrocarbons (PAHs) are neutral compounds containing multiple aromatic fused rings that are present in fossil fuels and can be formed from the incomplete combustion of organic material. In recent years, it has been well documented that several PAHs can be potentially carcinogenic via exposure or ingestion.

In this application note, we analyze 16 PAHs by LC/CMS (EPA 610 Mix) on the EPA priority target list using the Advion expression Compact Mass Spectrometer (CMS) coupled with the Advion AVANT UHPLC system.