A: The Rappsilber Laboratory is interested in studying the machinery of life, in particular protein structures and their interactions in living cells. Determining protein behaviour is crucial for developing new drugs or understanding terrible diseases such as cancer. We are doing this by developing state-of-the-art methods and new chemical tools for crosslinking mass spectrometry (crosslinking-MS), including new crosslinker reagents and crosslinking chemistry. Working on the chemistry-biology interface, our work encompasses chemical synthesis of peptides, fluorophore tagged sensors, peptide- and protein-reactive crosslinking reagents and bioorthogonal metal catalysts.
Q: WHAT WAS YOUR PREVIOUS WORKFLOW OR CHALLENGES?
A: This year (2020) we built a chemistry lab from scratch, here at the Institute of Biotechnology (TU Berlin). We had the opportunity to really think about our work flow requirements and create the most efficient chemical synthesis pipeline for a modern, 21st century, small chemistry laboratory. However, we are a satellite campus, located more than 10 km from the Institute of Chemistry, which meant that we were constrained by the lack of usual chemistry infrastructure. One of the major challenges that we faced here, is that without chemistry-specific analytical capability, we are working almost blind. Every step of chemical synthesis, including reaction monitoring, work-up, purification and final product characterisation required an exhausting and disruptive journey across Berlin!
Q: WHY DID YOU INCORPORATE THE EXPRESSION® CMS INTO YOUR LABORATORY?
A: We operate an advanced proteomics facility, with cutting edge, high-precision, high sensitivity mass spectrometers for analysing extremely complex peptide mixtures. But a chemist needs a workhorse, not a Formula 1 car. The Advion Interchim Scientific expression® CMS was a no-brainer. We needed a system that is versatile, compact, easy-to-use, easy-to-maintain (~10 minute calibration), robust and allows fast analysis (result in <30 seconds). This system is all of this, but furthermore it is a delight to use. The ASAP® Direct Analysis Probe works fantastically well for analysis of solids and liquids. Switching between APCI and ESI is so quick and easy. The Plate Express® system makes it a joy to identify reaction products directly from TLC plates, greatly simplifying subsequent purifications. The Plate Express™ also works really well for identifying synthesized peptides from TLC spots. The expression® CMS sits at the heart of our chemistry lab and workflow.
Q: WHO WOULD YOU RECOMMEND TO PURCHASE THE EXPRESSION® CMS?
A: We would recommend the Advion Interchim Scientific expression® CMS to literally any research laboratory, big or small. The versatility of the system is truly impressive.
A: The research of the new Institute for Drug Discovery seeks to combine computational and experimental efforts to investigate proteins and their interactions with small molecule substrates. The Medicinal Synthetic Chemistry Core is part of the new institute and responsible for the synthesis of potentially bio-active compounds based on the computational results predicting a high binding affinity to the proteins’ active sites.
Q: WHAT WAS YOUR PREVIOUS WORKFLOW OR CHALLENGES?
A: Previously, we separated all unknown by-products of our synthesis in order to investigate their structure based on NMR and external mass spec service. This time wasting workflow often resulted in a dead-end strategy with low efficiency.
Q: WHY DID YOU INCORPORATE THE expression® CMS INTO YOUR LABORATORY?
A: Since the purchase of the CMS, we improved our strategic synthesis planning extraordinarily. By using Plate Express™ as TLC-Interface together with the expression® CMS, the by-products could become quickly separated on TLC-plates and directly analyzed by mass spectrometry afterwards. Now we see it, now we know it, and we get it quickly purified.
Q: WHO WOULD YOU RECOMMEND TO PURCHASE THE expression® CMS?
A: I will highly recommend the CMS to all research institutes with a strong synthetical and natural product background of small molecules.
Successfully completing an organic synthesis involves three typically lengthy, but crucial steps: reaction monitoring, compound identification, and purification. These steps can create bottlenecks in the synthesis, unless a purpose-built, streamlined, and reliable workflow is on hand.
This whitepaper delves into some of the challenges faced by synthetic organic chemists as they navigate compound identification and purification struggles. It also describes how using a workflow that couples thin layer chromatography (TLC) and mass spectrometry (MS) to flash purification can help increase the efficiency of the entire process.
Key Objectives：
Understand how a workflow that combines thin-layer chromatography, mass spectrometry, and flash purification can increase the speed and efficiency of an entire organic synthesis process.
Learn about prep-free techniques that have become the new standard: scraping TLC spots, developing flash methods and performing long liquid chromatography/MS runs are not necessary with modern instrumentation that is specifically developed to take the prep-work and guess-work out of the purification process.
Become informed about a cost-effective, user-friendly benchtop workflow solution for organic compound identification and purification that can save time and money for any lab.
Rey Juan Carlos University, Complutense University of Madrid, University Rennes
Abstract
Lichens produce unique secondary metabolites with a rich potential as bioactive compounds. In many cases, the use of these molecules is limited by the low concentration of these compounds in thalli, low growth rate in culture, and changes in chemical patterns between thalli and aposymbiotic culture. In addition, the massive collection of some species of industrial interest can cause damage to lichen diversity and the associated environment. Six lichenized fungi (Arctoparmelia centrifuga, Parmelia saxatilis, Parmelina tiliacea, Platismatia glauca, Xanthoparmelia tinctina, and Usnea ghattensis) with biotechnological interest and belonging to Parmeliaceae have been cultured in order to test culture conditions and obtain enough biomass for further studies. In addition, we analyzed the compounds synthetized in axenic conditions and they were compared with chemosyndromes identified in complete thalli. Arctoparmelia centrifuga, P. saxatilis, P. tiliacea and X. tinctina were successfully cultivated while for P. glauca and U. ghattensis we only obtained sporulation and germination of the spores. The chemical pattern of the compounds secreted into the culture media varied significantly from the chemosyndrome of the whole thallus. Phenolic compounds of pharmacological and industrial interest (usnic acid, aspicilin, α-alectoronic acid, physodic acid, lobaric acid and nordivaricatic acid) and a wide variety of potentially bioactive compounds were obtained during the culture process.
Analysis was performed by LC/MS using the Advion Interchim Scientific® expression® Compact Mass Spectrometer (CMS).
New 1-hydroxy-10-alkylacridin-9(10H)-one BF2-chelates absorb in the blue-green part of the electromagnetic spectrum and emit fluorescence with moderate quantum yields of 8–45% in toluene. The dyes show large Stokes shifts about 4300 cm−1, decay times between 5 ns and 15 ns in toluene and high photostabilities. Introduction of a fluorine atom into the acridone cycle results in an increase of the fluorescence quantum yield and decay time whereas immobilization in a rigid polymer matrix (polystyrene) further extends the lifetime up to 18 ns. Large Stokes shifts and long emission decay time make this dye class an interesting platform for time-resolved imaging and sensing applications.
Analysis was performed with APCI ionization on the Advion expressionL Compact Mass Spectrometer (CMS).
The compound synthesis, purification and confirmation processes often present challenges. From ensuring successful synthesis of your product, setting up a flash purification method, and finally confirming ID of fractions, the lengthy work flow can be time consuming and repetitive.
This webinar will provide a foundation for flash purification processes, and will showcase a novel work flow concept that breaks down the process in to easy steps for optimal success. We will offer tips to optimize each essential segment of the workflow, and share seamless steps to quickly and easily drive the process from reaction monitoring to flash purification and fraction ID.
Presented by Dr. Daniel Eikel, Director of Customer Service and Product Applications, Advion.
This webinar was hosted by C&EN and recorded 8/13/20.
Mass spectrometry is an analytical technique used to determine the mass-to-charge ratio of ions in a sample and therefore the sample composition. This method is used across many industries including food and beverage, environmental monitoring, and clinical. There are many features of mass spectrometers that must be considered before purchasing such as the required mass analyzer technology, ionization source, and dissociation technique. Join Lab Manager and our panel of experts as we discuss how to decipher mass spectrometry technology offerings and find the right solution for your lab.
As an attendee, you will learn more about:
Available technology for performing mass spectrometry
Features to consider when purchasing mass spectrometry instruments
How to find the right mass spectrometer for your application
Pacific Northwest National Laboratory, Clemson University
Abstract
A new, multi-electrode, liquid sampling glow discharge ionization source for mass spectrometry is described. This ion source consists of multiple (2–4) counter (anode) electrodes in comparison to prior single counter electrode designs of this type. In the experiments presented here these ion sources have been interfaced with ThermoScientific Exactive Orbitrap instruments and Advion Interchim Scientific® expression® Compact Mass Spectrometer (CMS) instruments. Advantages and analytical performance improvements are described. These include the ability to use higher plasma currents, resulting in a more robust and energetic plasma exhibiting higher sensitivity, lower spectral background, ppt detection limits, and 2–3× faster washout times. A low-cost, 3D printed version of a dual counter electrode design is also described. The ion source can further be utilized in either atomic (elemental/isotopic) or molecular (molecular ion, fragmentation) ionization modes.
The combination of the Advion Interchim Scientific expression® CMS and puriFlash®flash chromatography technologies speed up the synthesis, purification and characterization of a compound.
Using the Advion Interchim Scientific expression®Compact Mass Spectrometer, the Plate Express™ TLC Plate reader, the ASAP® Atmospheric Solids Analysis Probe, and the puriFlash®XS520 flash purification system, it is now possible to execute a fast, user-friendly workflow to run TLC, harness the power of your cell phone to develop a flash method, and finally utilize a simple dipping probe to confirm fractions in seconds.
With easy sampling techniques, intuitive software, and advanced detection technology, you can easily and confidently synthesize, purify and characterize your compound, in a flash.
The collection of solid particulates and liquids from surfaces by the use of cloth swipes is fairly ubiquitous. In such methods, there is a continuous concern regarding the ability to locate and quantitatively sample the analyte species from the material. In this effort, we demonstrate the initial coupling of an Advion Plate Express plate reader to a liquid sampling–atmospheric pressure glow discharge (LS-APGD) microplasma ionization source with an Orbitrap mass spectrometer to perform uranium isotopic analyses of solution residues on cotton swipes. The Plate Express employs a sampling probe head to engage and seal against the swipe surface. Subsequentially, the analyte residues are desorbed and transported within a 2% HNO3 electrolyte flow to the ionization source. Quantitative recoveries were observed following a single 30 s extraction step, with the absolute mass sampled per extraction being ∼100 ng. While the intrasample variability in the analytical responses for triplicate sampling of the same swipe yield ∼30% RSD, this lack of precision is offset by the ability to determine isotope ratios for enriched uranium specimens with a precision of better than 10% RSD. Pooled, intersample precision (n = 9) was found to be <5%RSD across the various sample compositions. Finally, 235U/238U determinations (ranging from 0.053 to 1.806) were accurate with errors of <10%, absolute. The 234U- and 236U-inclusive ratios were determined with similar accuracy in enriched samples. While the driving force for the effort is in the realm of nuclear nonproliferation efforts, the ubiquitous use of cloth swipes across many application areas could benefit from this convenient approach, including the use of versatile, reduced-format mass spectrometer systems.
