Justus Liebig University Giessen, University of Modena and Reggio Emilia
Abstract
Effect-directed analysis (EDA) by the combination of high-performance thin-layer chromatography (HPTLC) with biologi- cal and enzymatic assays represents one of the latest tools available for the rapid bioprofiling of complex matrices, such as plant extracts. In this ambit, the aim of this project was the non-targeted screening of inflorescence extracts from ten different hemp varieties for components exhibiting radical scavenging, antibacterial, enzyme inhibiting and estrogen-like effects.
The characterization of two prominently multipotent bioactive com- pound zones was finally achieved by HPTLC-HRMS and preliminary assigned as cannabidiolic acid and cannabidivarinic acid.
HTPLC analysis was coupled via the Advion Plate Express® TLC Plate Reader.
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.
The compound synthesis, purification and confirmation process often presents challenges throughout. 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.
In this application note, we demonstrate how the combination of Advion Interchim Scientific technologies speed up the synthesis, purification and characterization of a compound.
This series features the Advion Interchim Scientific expression® Compact Mass Spectrometer (CMS), the Plate Express™ TLC Plate Reader, the Atmospheric Solids Analysis Probe (ASAP®), and the puriFlash® XS520 flash purification system.
The combination of the Advion Interchim Scientific® expression® CMS puriFlash® flash chromatography technologies speed up the synthesis, purification and characterization of a compound.
Martin-Luther-University Halle-Wittenberg, Free University of Berlin
Abstract
Cannabis products have been used in various fields of everyday life for many centuries, and applications in folk medicine and textile production have been well-known for many centuries. For traditional textile production, hemp fibers were extracted from the stems by water retting in stagnant or slow-moving waters.
During this procedure, parts of the plant material‚ among them phytocannabinoids‚ are released into the water. Cannabinol (CBN) is an important degradation product of the predominant phytocannabinoids found in Cannabis species. Thus, it is an excellent indicator for present as well as ancient hemp water retting.
In this study, we developed and validated a simple and fast method for the determination of CBN in sediment samples using high-performance thin-layer chromatography (HPTLC) combined with electrospray ionization mass spectrometry (ESI-MS), thereby testing different extraction and cleanup procedures‚ as well as various sorbents and solvents for planar chromatography.
This method shows a satisfactory overall analytical performance with an average recovery rate of 73%. Our protocol enabled qualitative and quantitative analyses of CBN in samples of a bottom sediment core‚ having been obtained from a small lake in Northern India, where intense local retting of hemp was suggested in the past. The findings correlate with existing records of Cannabis-type pollen. Thus, the method we propose is a helpful tool to track ancient hemp retting activities.
The Advion TLC/CMS system with the expression® Compact Mass Spectrometer (CMS) and Plate Express® TLC Plate Reader was utilized for the elution of compounds from the HPTLC plates.
Constructive machine learning aims to create examples from its learned domain which are likely to exhibit similar properties. Here, a recurrent neural network was trained with the chemical structures of known cell‐migration modulators. This machine learning model was used to generate new molecules that mimic the training compounds. Two top‐scoring designs were synthesized, and tested for functional activity in a phenotypic spheroid cell migration assay. These computationally generated small molecules significantly increased the migration of medulloblastoma cells. The results further corroborate the applicability of constructive machine learning to the de novo design of druglike molecules with desired properties.
Analysis was performed by TLC/MS using the Advion expression Compact Mass Spectrometer (CMS) and Plate Express TLC Plate Reader.
Leiden University, Eindhoven University of Technology
Abstract
The structure of the copper complex of the 6-((1-butanethiol)oxy)-tris(2-pyridylmethyl)amine ligand (Cu-tmpa-O(CH2)4SH) anchored to a gold surface has been investigated. To enable covalent attachment of the complex to the gold surface, a heteromolecular self-assembled monolayer (SAM) of butanethiol and a thiol-substituted tmpa ligand was used…These results show that upon immobilization of Cu-tmpa-O(CH2)4SH, the resulting structure is not identical to the homogeneous CuII-tmpa complex. Upon anchoring, a novel CuI species is formed instead. This illustrates the importance of a thorough characterization of heterogenized molecular systems before drawing any conclusions regarding the structure–function relationships.
Thanks to the diminishing size and cost of mass spectrometers, coupled with their increasing robustness and ease of use, universities are now starting to furnish their undergraduate chemistry laboratories with this advanced analytic tool.
“My favorite learning environment is the laboratory,” explains Paul A. Flowers, professor of analytical chemistry at University of North Carolina at Pembroke. “I like teaching students fundamentals through bona fide research experiences.” Flowers began using mass spectrometry in the teaching laboratory about six years ago and hasn’t looked back.
Learn more about the integration of mass spectrometry for teaching with this free whitepaper.
Advion Interchim Scientific’s Plate Express® is ideal for fast, easy TLC/MS analysis. Coupled with the expression® Compact Mass Spectrometer (CMS), the TLC plate reader allows prep-free sampling and data in less than 30 seconds.
