Page 26 - Shimadzu Journal vol.2 Issue1
P. 26

Topics                                                                                                                                                                                                                                 Topics




            Fig. 5 shows the recovery rates and peak shapes when a dilution   6. Use in Other Applications
            trap is used with indomethacin samples likewise spiked with   6.1 Application to Cleaning Validation                                                        Isopropylantipyrine
            plasma, and large-volume 100 µL, 200 µL, and 500 µL samples are
            injected. Even with the 500 µL injection, a recovery rate of almost   Cleaning validations for pharmaceutical production equipment
            100 % is achieved, and the peak shape is maintained.  require high-sensitivity analysis. However, the samples used for
                                                               measurement are often dilute organic solvents. As a result,
                                                               pretreatment to concentrate samples is required; this can
                                                               sometimes lower throughput. In cleaning validations, Co-Sense for
                                                               BA enables direct, large-volume injection without concentrating
                                                               the samples, which heightens efficiency.
                                                               In reversed phase mode, when organic solvents and other solvents
                                                               with strong elution properties are injected in large volumes as the                              100 µL injected
                                                               sample solvent, peak shapes tend to worsen and there may be
                                                               problems with retention times. In cleaning validations for                                        10 µL injected
                                                               pharmaceutical production equipment, ethanol and other organic
                                                               solvents are often used as the sample solvent, which hinders                                                                Fig. 9 Chromatograms for Indomethacin in an IgG Solution
                                                               large-volume injection for high-sensitivity analysis. In addition,      Fig. 8 Chromatograms for Isopropylantipyrine/Ethanol Solutions
                                                               with ordinary trap injections, recovery rates may decrease due to           Using Co-Sense for BA                         The following shows an example of the analysis of
                                                               elution of intended components from the trap column. As a result,                                                         indomethacin-derived impurities. Fig. 10 shows the chromatogram
                        Fig. 4 Effect of On-Line Dilution      in LC analysis for cleaning validation, the sample is often                                                               from an analysis of indomethacin utilizing an ordinary LC system.
                                                               concentrated in advance, leading to decreased throughput.                                                                 Impurities of 0.07 % are detected. Fig. 11 shows the
                                                                                                                                      6.2 Analysis of Free Bodies and Impurities in Antibody-Drug
                                                                                                                                      Conjugates                                         chromatogram from the analysis of a sample mixture of
                                                                                                                                                                                         indomethacin and IgG in a 1:1 molar ratio using Co-Sense for BA.
                                                                                                     Isopropylantipyrine              According to the FDA, investigational new drug (IND) applications   The impact of the antibodies is eliminated, the recovery rate is 100
                                                                           Isopropylantipyrine
                                                                                                                                      for antibody-drug conjugates (ADC) have increased markedly since   %, and a CV of 2.8 % is achieved. In addition, using LC/MS for
                                                                                                                                      2008, and profiles for free bodies and process-derived impurities   detection makes it possible to reliably identify the presence of
                                                                                                                                      are also being discussed [14].                     drug-derived impurities, even in ADCs.
                                                                                 50 µL injected    100 µL injected
                                                                                 10 µL injected                                       In the analysis of impurities and free bodies contained in ADCs,
                                                                                                    10 µL injected                    deproteinization is required to eliminate high-concentration
                                                                       Direct Injection         Trap Injection                        antibodies. If deproteinization is performed using organic solvents
                                                                                                                                      or acids as a sample pretreatment, the impact of the sample
                                                               Fig. 6 Chromatograms for   Fig. 7 Chromatograms for                    solvent may worsen peak shapes, and enhancing the sensitivity via
                                                                    Isopropylantipyrine,     Isopropylantipyrine,                     large-volume injections is often difficult. In addition, for samples
                                                                    with Direct Injection of   Trapping Injection                     with a high organic solvent ratio after deproteinization, the
                                                                    an Ethanol Solution      without Dilution
                                                                                                                                      recovery rate may decrease with the ordinary trap injection
                Fig. 5. Stability for Large-Volume Sample Injections                                                                  method due to the impact of the sample solvent. Furthermore, if
                                                                                                                                      on-line pretreatment (on-line solid phase extraction) is performed
                                                               Fig. 6 shows the chromatograms when isopropylantipyrine/ethanol        in order to automate the deproteinization, the recovery rate for
                                                               solutions are analyzed using direct injection, and when a trapping
            5. Method Validation in Bioanalysis                                                                                       the intended impurities may decrease due to antibody and   Fig. 10 Chromatogram for Indomethacin Using Normal LC Analysis
                                                               injection is used without on-line dilution. In large-volume (50 µL)
            At the FDA and EMA, guidance and guidelines are enacted with   injections via the direct injection method, the isopropylantipyrine   drug-derived impurity interactions.
            respect to the validation of methods for analyzing the   peak is leading due to the impact of the sample solvent. In      With the Co-Sense for BA dilution trap method, components can
            concentration of drugs in biological samples (Bioanalytical Method   addition, in trap concentration without on-line dilution, elution   be trapped reliably, even with large-volume injections, to enhance
            Evaluation: BMV). In July 2013, the Japanese Ministry of Health,   from the trap column occurs due to the impact of the sample   sensitivity, thanks to antibody removal (deproteinization) and the
 With Co-Sense for BA, the injected sample is diluted at a constant   Labour and Welfare also issued BMV guidelines. The thinking   solvent, and the recovery rate decreases. (The peak for a 100 µL   suppression of antibody and impurity interactions. Fig. 9 shows
 rate. This is performed to suppress interactions between intended   behind ISR (Incurred Samples Reanalysis: evaluation of   injection does not equal 10 times that of a 10 µL injection.)  the chromatograms from an analysis of indomethacin in IgG using
 components and proteins in the sample, and to release intended   reproducibility for measurement values from actual samples) and   In sample injections via the Co-Sense for BA dilution trap, even   Co-Sense for BA. The sample is an acetonitrile solution of 1
 components bound to proteins. In this way, even components   other aspects of the European and American guidelines were   with this sort of large-volume injection of organic solvents, the   mg/mL IgG and 2.5 ng/mL indomethacin. (The molar ratio of the
 with a high binding rate are reliably trapped and concentrated. A   introduced, and its importance emphasized.  sample is introduced to the trap column while on-line dilution is   indomethacin added is approximately 0.1 % that of the
 liquid containing a buffer solution and a low-concentration   At first glance, Co-Sense for BA appears to be a complicated   performed using water or a buffer solution. As a result, reliable   antibodies.) The recovery rate when diluted is 99.6 %. However,
 organic solvent is used as the dilution solvent. As a result, even   system, and there might be qualification-related concerns.   trap concentrations are possible even if guard and other generic   the recovery rate drops to 72.3 % when not diluted. Utilizing
 plasma and serum samples can be injected directly. In addition,   However, utilization of this system not only concentrates samples   columns are used as the trap column. In addition, the intended   on-line dilution breaks the non-covalent bonds, avoiding a
 high sensitivity is achieved due to excellent recovery rates and   but also reduces matrix effects in MS analysis. As a result, in terms   components are introduced to the analysis column by valve   decrease in the recovery rate.
 peak shapes, even for large-volume injections [6], [7], [9], [10],   of the ongoing issue of method validation, the attainment of more   switching after concentration in the trap column, so excellent
 [12], [13].  reliable results is anticipated. In addition to generally enforced   peak shapes can be obtained. The high-sensitivity analysis of
 Fig. 4 shows a comparison of recovery rates based on the presence   accuracy, precision, reproducibility, and linearity evaluations, both   isopropylantipyrine in ethanol is difficult for ordinary systems, but
 or absence of on-line dilution, utilizing indomethacin samples   between-day and within-day variance have also been evaluated,   with Co-Sense for BA, an approximately 100 % recovery rate and
 spiked with plasma. With dilution, the recovery rate is almost 100   and excellent results have been obtained [7], [8], [10], [12], [13].  excellent peaks shapes are obtained even with 100 µL injections.
 %. Without dilution, the recovery rate falls to approximately 50 %.  Fig. 8 shows the chromatograms when isopropylantipyrine/ethanol                                                     Fig. 11 Chromatogram for Indomethacin in IgG Using Co-Sense for BA
                                                               solutions are analyzed with Co-Sense for BA.






      52                                                                                                                                                                                                                                      53
   21   22   23   24   25   26   27   28   29   30   31