CAMAG TLC-MS INTERFACE

Transcription

1 CAMAG TLC-MS INTERFACE m/z WORLD LEADER IN PLANAR-CHROMATOGRAPHY

2 Identification and elucidation of unknown substances by hyphenation of TLC / HPTLC and MS The CAMAG TLC-MS Interface is the versatile instrument for rapid and contamination-free elution of TLC / HPTLC zones directly from the layer and subsequent online transfer into any mass spectrometer. The mass spectrometric identification of substances separated by TLC/HPTLC has been known for a long time. However, in the past the target zones had to be scraped off from the plate, extracted into a tube and transferred offline into the MS system. Hyphenation of HPLC with different MS systems is also well known but not all analytes may be separated by HPLC, e.g. due to no or low detectability in the UV range, heavy matrix load or a lack of MS compatible solvents. In this case HPTLC may be a more efficient separation technique. Now a very convenient and universal TLC-MS Interface is available that can extract the zones of interest and direct them online into MS systems of various brands and techniques (APCI-MS, APPI-MS or ESI-MS). The great advantage of the instrument is that exclusively questioned zones are transferred into the MS for identification and that within less than one minute sensitive mass spectrometric information is available. The TLC-MS Interface extracts circular zones as well as zones in the form of bands from a TLC / HPTLC plate. For the extraction methanol or any other appropriate solvent can be used at the standard flow rate of the HPLC-MS system (e.g. 0.1 ml / min). The elution head is positioned with the integrated laser crosshairs or based on the coordinates determined by the CAMAG TLC Scanner or TLC Visualizer. After extraction the eluate is either transferred online into the mass spectrometer or collected in a sample vial for further offline analysis Identification of alkaloids oxymatrine, sophoridine and matrine in Sophora flavescens extract. HPTLC plate after extraction of zones with the TLC-MS Interface. Confirmation of matrine, m/z 249 [M+H] m/z 2

3 Features of the TLC-MS Interface Rapid and contamination-free elution of selected zones Online transfer into the mass spectrometer Compatible with all conventional HPLC-MS systems Identification of unknown substances at a limit of detection as known from HPLC-MS Low solvent consumption Note With the TLC-MS Interface the analyte is more efficiently dissolved from the layer than by extracting a zone scraped off from the plate. The process corresponds to the chromatographic elution with a very polar solvent we therefore use the term elution. The TLC-MS Interface can be installed plug & play into any given HPLC-MS system. The instrument can be used stand-alone to collect eluates for offline transfer into NMR, (ATR)-FTIR, EI-MS, MALDI i CAMAG TLC-MS Interface 3

4 THE PRINCIPLE OF TLC-MS HYPHENATION Solvent HPLC-Pump Flow rate µl/min MS-System CAMAG TLC-MS Interface 4

5 Pump m/z TLC-MS Interface in position "Elution" Solvent input Solvent output Mass spectrum Once the elution head is lowered the solvent moves through the elution head and elutes the zone (which was previously positioned by the laser crosshairs). The eluate is directed through the integrated frit and a capillary into the MS system. In position Bypass the solvent flow is directed into the MS system. Plate / Foil Frit x Laser projects laser crosshairs Technical data Cutting edges Zone Elution heads i Dimensions and weight with standard plate support Width: 230 mm, depth: 408 mm, height: 275 mm Net weight: 11 kg 4 Elution head round, diameter 4 mm for layer thickness up to 300 µm Laser crosshairs Laser: 5 mw, class 2M, battery operated (two batteries 1.5 V, AA or LR6), operating time on batteries: up to 100 hours Materials Elution head: made of passivated stainless steel, resistant to all common solvents Frit: 2 µm stainless steel with PCTFE ring Requirements Gas connection: compressed air or Nitrogen 4 6 bar Solvent flow rate: µl / min Pressure of elution head onto HPTLC plate: max 400 N Elution head oval, 4 2 mm for layer thickness up to 300 µm Elution head round, diameter 5 mm for layer thickness up to 500 µm (preparative chromatography) CAMAG TLC-MS Interface 5

6 APPLICATION EXAMPLES HPTLC-MS identification of Coenzyme Q10 in cosmetics HPTLC separation and identification of ginsenosides in Ginseng extracts Extracts of different Ginseng species S 3 R 6 S 3 R 7 S 4 R 8 S 4 Reference standards Q-10 HPTLC separation (excerpt of chromatogram) of Q10 standards (R6 R8) and two cosmetic samples (S3, S4), image of plate after elution of Q10 HPTLC chromatogram of Ginseng extracts and standards; left: derivatized with methanolic sulfuric acid for visual evaluation, right: same tracks without derivatization for elution with the TLC-MS Interface and identification by MS. The vitamin-like substance Coenzyme Q10 (ubiquinone) is naturally present in human cells. It is an antioxidant and protects skin cells from aggressive oxygen radicals. Q10 is used as an ingredient in many different cosmetic products like creams, lotions, and gels. The analysis of Q10 in these complex mixtures is done by HPTLC followed by identification in MS. HPTLC-MS hyphenation with the Agilent TOF 6210 Ginseng belongs to the plant family of Araliaceae and grows in the eastern part of North America, northeastern China and Korea. Asian Ginseng root is harvested after 4 to 6 years and the peeled and dried root is marketed as White Ginseng. Its main active compounds are ginsenosides and essential oils. Asian Ginseng powder and tea has been used for centuries in Traditional Chinese Medicine as a universal stimulant. The goal of the presented work was the identification of the main compounds in Ginseng extracts by HPTLC separation followed by elution of zones with the TLC-MS interface. Mass spectrometry With the TLC-MS Interface equipped with the round elution head (diameter 4 mm) and connected to an Agilent Quadrupol 6140 MS system operating in positive and negative APCI mode, extraction of zones with acetonitrile water 95:5 with 0.1 % of formic acid at a flow rate of 0.2 ml/min. Coenzyme Q10 (ubiquinone): C 59 H 90 O 4, TOF mass spectrum of the Q10 Monoisotopic mass Da zone eluted from the HPTLC plate with the TLC-MS Interface Determination of the exact mass and structure confirmation of C 59 H 90 O 4. Conclusion The TLC-MS Interface allowed the unequivocal identification of typical compounds present in Ginseng extracts, e.g. Ginsenosides Rg1 and F11. Typical fragments of ginsenoside Rg1 Correlation of calculated and measured mass: difference < 2 ppm (in this example 0.92 ppm). [M + Na] + ; Da Conclusion By automated multiple development with the AMD2 the HPTLC analysis of Q10 is very feasible, even in complex cosmetic samples. The TLC-MS Interface offers a rapid and easy solution for the reliable identification of Q10. Top: Elution profile of the substance zone (TIC); bottom: mass spectrum of Rg1 (identical to MS of reference samples). 6

7 Rapid HPTLC-MS identification of synthesis products Educt Synthesis Synthesis Synthesis Synthesis Reference Final Step 1 Step 2 Step 3 Step 4 Product HPTLC separation of the educt, the four intermediates and the product of the DMS-CI synthesis, each in double application (left 1 µl, right 5 µl.). 1,2,3,4-Tetrahydroisoquinolines (TIQs) have gained interest in relation to Parkinson s disease. For the specific detection recently a very sensitive derivatization reagent has been developed: 4-(5,6-dimethoxy-2-phthalimidinyl)-2-methoxyphenyl sulfonyl chloride (DMS-Cl) reacts quantitatively with TIQs to form fluorescent sulfonamides, which can then be analyzed by HPLC. Because DMS-CI was not commercially available we tried to synthesize it during our student projects at the University of Applied Sciences Northwestern Switzerland and to characterize all steps of the synthesis by HPTLC and MS. Synthesis of DMS-CI Correlation of calculated and measured mass: difference < 2 ppm. The proposed structure was confirmed by a very good correlation of the calculated and measured isotope ratio. All steps of the synthesis were separated by HPTLC and the molecule masses were identified by MS. HPTLC-MS hyphenation with the Agilent TOF 6210 Correlation of calculated (purple columns) and measured (green curve) isotope ratio. Conclusion The TLC-MS Interface offers a very rapid and easy solution to separate the educt, the four intermediates and the product of the synthesis by HPTLC, to determine the exact masses by TOF-MS and to confirm all structures with high probability. TOF mass spectrum of the zone corresponding to the product of the synthesis, eluted from the HPTLC plate with the TLC-MS Interface The complete application examples and further details are available at i CAMAG TLC-MS Interface 7

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