Page 65 - Application Handbook - Liquid Chromatography
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            750000000 2:169.00( − )                                           Inten. (×1,000,000)
                                                                            2,0  169,1
            500000000                                                       1,5                                                                                Comprehensive Two-dimensional Liquid
            250000000        Gallic acid                                    1,0        339,1
                                                                            0,5                                                    Technical                   Chromatography for Determination of
                 0                                                          0,0
                                                                                                                                   Report                      Polyphenols in Red Wines
                     40.0  45.0  50.0  55.0  60.0  65.0  70.0  75.0  80.0  85.0  90.0  95.0  min  150  250  350  450  550  650  750 m/z
                                                                              Inten. (×1,000,000)
            400000000 2:577.00( − )                                                                                                                            LC×LC-PDA-MS/MS for polyphenol analysis in red wine
                                                                                                  577,1
            300000000  Procyanidin B1                                       1,0
            200000000                    Procyanidin B2
                                                                                                                                                                                                    1
                                                                                                                                                                                     1
                                                                                                                                                                                                               1
                                                                            0,5  212,1     443,2                                                               Paola Dugo 1, 2 , Francesca Rigano , Francesco Cacciola , Paola Donato , Luigi Mondello  1, 2
            100000000                                                          141,1  295,1
                                                                            0,0
                 0                                                            150  250  350  450  550  650  750 m/z
                     40.0  45.0  50.0  55.0  60.0  65.0  70.0  75.0  80.0  85.0  90.0  95.0  min
                                                                                                                                   Abstract:
                                                                              Inten. (×1,000,000)
            750000000 2:289.00( − )                                         2,5       289,1                                        A comprehensive two-dimensional liquid chromatography method was developed and applied to the determination of polyphenols in red wines.
                                                                            2,0
            500000000                                                                                                              To fulŠl such a task, a micro cyano and a partially porous octadecylsilane columns were employed in the Šrst and the second dimension, respec-
                                                                            1,5
                         Catechin                                           1,0                                                    tively in combination with photodiode array and mass spectrometry (LC×LC-PDA-MSMS) detection. To increase the peak capacity values by using
            250000000                           Epicatechin                                                                        RP modes in both dimensions, a comparison of a conventional full-in-fraction and shifted second dimension gradient  was carried out. The
                                                                            0,5 141,1 212,1  349,1  579,1
                 0                                                          0,0                                                    separation  capabilities  of  the  comprehensive  LC  approaches  tested  allowed  the  analysis  of  such  a  complex  natural  sample  without  any
                     40.0  45.0  50.0  55.0  60.0  65.0  70.0  75.0  80.0  85.0  90.0  95.0  min  150  250  350  450  550  650  750 m/z  pre-treatment to effectively reduce the interferences coming from the matrix.
                                                                              Inten. (×100,000)                                    Keywords: comprehensive LC, polyphenols, red wines, mass spectrometry
            100000000 2:301.00( − )
                                                                            7,5 141,1  277,2
             75000000
             50000000                                                       5,0      301,1
                                              Quercetin                          212,1
             25000000                                                       2,5
                                                                                                                                                                                      2. Experimental
                                                                                                                                   1. Intr oduction                                   2. Experimental
                                                                                                                                   1. Introduction
                 0                                                          0,0
                     40.0  45.0  50.0  55.0  60.0  65.0  70.0  75.0  80.0  85.0  90.0  95.0  min  150  250  350  450  550  650  750 m/z
                                                                                                                                   Phenolic  compounds  are  secondary  metabolites  synthesized  by  plants   2-1. Reagents and Materials
              Fig. 6  Ion extracted chromatograms (on the left) along with relative mass spectra (on the right) of the main polyphenolic compounds identi ed  during normal development and in response to stress conditions. They em-
                   in the red wine sample investigated                                                                                                                                LC-MS grade solvents for LC×LC analyses: water (H 2 O), acetonitrile
                                                                                                                                   brace a considerable range of substances possessing an aromatic ring bear-
                                                                                                                                                                                      (ACN); Acetic acid 99–100%, (glacial). All the solvents and chemicals
                                                                                                                                   ing one or more hydroxyl moieties. Produced and consumed world-wide,
                                                                                                                                   wine is an excellent natural source of various polyphenol families that go   were purchased from Sigma-Aldrich (Milan, Italy).
            5. Conclusions                                                                                                         from phenolic acids (benzoic- or cinnamic-like derivatives) to different   Chromatographic separations were carried out using columns provid-
            5.
               Conclusions
            A  comprehensive  two-dimensional  liquid  chromatography  system,                                                     classes of flavonoids (flavones, flavan-3-ols, flavonols and anthocyanins).  ed by Supelco (Bellefonte, PA, USA): Ascentis Cyano (250 mmL. × 1
            based on the use of a micro cyano column and a partially porous (C 18 )                                                Sometimes, the polyphenol content in real world-samples can be so com-  mmI.D., 5 µm d.p.), and Ascentis Express C 18 (30 mmL. × 4.6 mmI.D.,
            column in the Šrst and second dimension, respectively, in combination                                                  plex that they cannot be resolved in a one-dimensional HPLC analysis. In   2.7 µm d.p.).
            with photodiode array and mass spectrometry detection, is presented.                                                   order to overcome this problem, comprehensive two-dimensional liquid   The red wine was purchased in a local market. The sample was œl-
            Two second dimension gradient approaches, namely full in fraction                                                      chromatography (LC×LC) employing two columns with different selectiv-  tered through a 0.45 µm Acrodisc nylon membrane (Pall Life Scienc-
            and shifted were investigated and compared in terms of peak capacity.                                                  ity in the two dimensions could be a viable tool. In addition, in order to   es, Ann Arbor, MI, USA) before injection.
                                                                                                                                   improve the peak distribution, different gradient elution strategies could
            The shifted gradient method used increased the effective peak-distri-
                                                                                                                                   be investigated to enhance the orthogonality degree, by means of specif-
            bution area in the LC×LC analysis of a red wine sample.
                                                                                                                                   ic elution gradient approaches to be used in the second dimension.
            Therefore, the use of a shifted gradient in an LC×LC system brings                                                     This technical report describes a novel LC×LC-PDA-MSMS (Fig. 1) instru-
            about a signiŠcant improvement in separation power and is a great                                                      ment, capable of extremely high-resolution power, as well as targeted
            advantage in the analysis of such complex samples.
                                                                                                                                   and untargeted analysis, that was successfully applied to the character-
                                                                                                                                   ization of the polyphenol content a red wine sample (Fig. 2).

                                                                                                First Edition: December, 2015


                                             For Research Use Only. Not for use in diagnostic procedures.
                                             The content of this publication shall not be reproduced, altered or sold for any commercial purpose without the written approval of Shimadzu.    Fig. 2  RP-LC×RP-LC Plot of a red wine sample
                                             The information contained herein is provided to you "as is" without warranty of any kind including without limitation warranties as to its
                                             accuracy or completeness. Shimadzu does not assume any responsibility or liability for any damage, whether direct or indirect, relating to the
                                             use of this publication. This publication is based upon the information available to Shimadzu on or before the date of publication, and subject   Fig. 1  LC×LC-PDA-MSMS instrumentation
                                             to change without notice.
       www.shimadzu.com/an/                                                                      © Shimadzu Corporation, 2015      1 University of Messina, Italy
                                                                                                                                   2 Chromaleont S.r.l.                                                                                   1
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