Page 10 - Shimadzu Nexera UC - Nexera UC Prep
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Purification





                     High recovery rate of preparative purification with excellent operability




                     In purification using SFC, the target compounds are recovered in high concentrations in an organic solvent, which saves time
                     not only during analysis, but also during post-run processing after preparative tasks are complete. The Nexera UC Prep
                     maximizes fractionation output with its high recovery rates and ability to carry out continuous preparative work that further
                     shortens the user’s waiting time.

                                                                                                                                            Stacked injection function eliminates waiting time
                                                                                                                                        Normal injection wastes time between peak elutions. Using the Nexera UC Prep’s stacked injection function, samples
                                                                                                                                        can be injected continuously without any waiting time, enabling more samples to be processed. Settings for this
                         SFC shortens analysis times                                                                                    function can be specified easily in the dedicated software Prep Solution.
                     Due to the low viscosity and high diffusivity of supercritical CO2, column backpressure for SFC is low even at high flow rates
                     which enables faster analysis without sacrificing column efficiency. This allows significantly shorter analysis times than HPLC.  Normal injection
                                                                                                                                                                 Fractionation
                                                                                                                                                     Waiting time

                                        HPLC
                                                                                                                                                                                                   3 injections



                                        SFC                                                                                                      Injection                           10.5 min
                                                                                                                                                                                                          3× more injections
                                                    1/4 of the analysis time                                                                     Stacked injection (9 consecutive injections)

                                                                                                                                                     Waiting time  Fractionation

                                      0          6              15               24     min                                                                                                        9 injections
                                           Comparison of HPLC and SFC (Chiral separation of Omeprazole)

                                                                                                                                                                                     10.5 min

                        High recovery rates                                                                                                      Injection   Chiral separation of warfarin
                     In preparative SFC, one factor that results in lower recovery rates is increased scattering of the eluent when the CO2 returns
                     from a supercritical to a gaseous state. The Nexera UC Prep’s patented gas–liquid separator, the LotusStream separator,   Simple post-run processing
                     successfully reduces sample dispersion and carryover, while also achieving high recovery rates. These high recovery rates can
                                                                                                                                        Because most of the mobile phase is vaporized supercritical CO2, only the organic solvent (modifier) added to
                     be obtained regardless of flow rate or modifier concentration, even for volatile compounds such as the fragrance linalool.
                                                                                                                                        change the polarity of the mobile phase remains after preparative work. Since there is no water content in the
                           Comparison for 1% linalool                                                                                   recovery fraction, the concentration time is significantly shorter.
                                                          LotusStream separator (patented technology)
                      Equipment          Recovery rate
                                                          Decreases flow rate without increasing the pipe   Eluent
                      Conventional separator  78.0%                                                                                                                                  Long concentration time
                                                          diameter by splitting flow through multiple
                      LotusStream Separator  96.7%        channels. The CO 2  is discharged externally while                                         Preparative HPLC
                                                          the liquid travels along the column and drips
                                                          directly into the collection vessel without
                                                          dispersing or scattering the eluate.                                                                         Water/MeOH
                                                                                                        CO 2
                                                                                                                                                                                 Short
                                                                                                                                                                              concentration
                                                                                                                                                                                 time
                                                                                                                                                     Preparative SFC
                                                                Watch videos                        Liquid

                                                                                                                                                                         MeOH



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