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Nexera UC UHPLC/SFC

 Efficient Method Development using the UHPLC/SFC Switching System



 When considering separation conditions, using both UHPLC and SFC can help to optimize conditions further.   The following describes an example of using the UHPLC/SFC switching system to increase the speed of method scouting. The
 The Nexera UC/s UHPLC/SFC switching system provides the ability to use both UHPLC and SFC analysis modes in   Nexera UC/s UHPLC/SFC switching system was used to automatically optimize the separation conditions for two chiral compounds
            (omeprazole and warfarin).
 a single system. The  gure below shows a  ow diagram for this system. The system was con gured by adding
              A total of 36 combinations of six chiral columns (CHIRALPAK  series) and the three mobile phases shown in the tables below
                                                             ®
 a supercritical carbon dioxide delivery unit and back pressure regulator unit to a standard UHPLC system. Both
            (18 combinations each for UHPLC and SFC) were evaluated.
 UHPLC and SFC analysis modes can be used by switching of delivery units (control mode ON or OFF) and
                                                                    Table 1  UHPLC Analytical Conditions for Chiral Compounds
 switching the pressure of the back pressure regulator.  SFC  UHPLC
                                                                       Mobile phase
 Sharing the solvent delivery unit (for pumping organic solvents), autosampler, column oven, and detector   Modi er  Mobile Phase  No.  (Upper: A and Lower: B)  Others
 for both SFC and UHPLC analysis minimizes space requirements and equipment cost and reduces equipment   No.1  No.2  No.3  No.1  No.2  No.3  Hexane  B Conc. (%)   : 20% (Isocratic)
            Column    (5)    (6)            (1)                  1      Ethanol     Flow Rate    : 2 mL/min
 downtime. In addition, an existing UHPLC system can be upgraded to this system.  IA  Column Temperature : 40 °C
                                                                                    Inj. Vol.    : 1  L
 By using the mobile phase solvent                               2      Hexane      Detection    : PDA@220 nm
                                                                      Isopropyl alcohol  Step GE
 switching valve in combination with the   IB                                           0 - 6 min  20%  Analysis
 column switching valve, mobile phase                            3  Methyl tertiary butyl ether  6 – 8 min  40%  Column washing
                      (2)    (4)                                        Ethanol        8 – 12 min  20%  Equilibration
 conditions can be changed automatically   IC
 and continuously for up to twelve                                   Table 2  SFC Analytical Conditions for Chiral Compounds
 columns to enable a wide variety of   ID                       No.     Modi er                Others
                                                                                    Modifier Conc. (%)  : 20% (Isocratic)
 conditions, improving method                                    1      Methanol    Flow Rate    : 3 mL/min
                                                                                    Column Temperature : 40 °C
 development ef ciency.  IE                                                         Inj. Vol.    : 1  L
                                                                                    BPR Press    : 10 MPa
                                                          (3)    2      Ethanol     Detection    : PDA@220 nm
                IF                                                                  Step GE
                                                                                        0 - 5 min  20%  Analysis
                                                                    Acetonitrile / Ethanol  5 – 7 min  40%  Column washing
                                                                 3
                    Chromatograms of omeprazole under 36 different     = 75 / 25 (v/v)  7 – 10 min  20%  Equilibration
                              analytical conditions

              Reproducibility for continuous switching
 UHPLC column
 Oven-A     Using the switching system, three drug components were analyzed by continuous switching between UHPLC and SFC
 SFC        analysis three times. The resulting chromatograms are shown in Fig. 10. The chromatograms show that reliable results
 Pump-A  Column
 Shutoff valve:  (for CO2)  switching valve  Manifold  were obtained, with no effects from switching  ow lines, even if mobile phases and separation characteristics are
 Open
            signi cantly different.
 Back pressure
 Liquid CO2  regulator control:  Switch from              Switch from              Switch from
 cylinder  Flow  ON  SFC (1)    SFC to UHPLC  UHPLC (1)   UHPLC to SFC  SFC (2)   SFC to UHPLC  UHPLC (2)
 Pump-B  switching valve  Detector
                  SFC (n = 5 for each)                        UHPLC (n = 5 for each)
 Autosampler           Propranolol    Indapamide                Propranolol  Indapamide
                      Ibuprofen
 Mobile phase                                                                Ibuprofen
 One UHPLC   (organic solvent-based)            After switching
 pump added to                                  from LC (SFC (2))                          After switching
 an SFC system                                                                             from SFC (UHPLC (2))
 Pump-C                                         Before switching                           After switching
                                                (SFC (1))                                  from SFC (UHPLC (1))
 Oven-B                   1.0          2.0   min                  1.0         2.0        min
 Mobile phase  SFC Column
 (water-based or buffer solution)  Chromatograms for three drug components, obtained by switching between UHPLC and SFC analysis modes
 LC
 Nexera UC/s UHPLC/SFC switching system and  ow line diagram (Equipment in green frame used for SFC)  Note: CHIRALPAK ®  is a registered trademark of Daicel Corporation.

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