Page 14 - Oligonucleotide Therapeutics Solution Guide
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Characteristic analysis
                  Quality Control

                     Sequence Confirmation                                                                                              MALDI-8020




                                                                                                                                           Features
                                  Simple Sequence Confirmation by
                                                                                                                                        The MALDI-8020 is the latest in a long line of MALDI-TOF products from Shimadzu. It is used for quality control and profiling of peptides, proteins,   Modification
                                                  MALDI-TOF MS                                                                          polymers and oligonucleotides. In order to maintain equipment performance for a long period of time, even benchtop types use large diameter ion   Target selection
                                                                                                                                        optics to reduce the risk of ion stain reduction. In addition, it is equipped with a UV laser quick automatic ion source cleaning function (TrueClean)
                                                                                                 click here                             that can clean the ion extraction electrode without dropping the vacuum. It also provides tools to centrally manage data and support strict
                                                                                                                                        adherence to 21 CFR Part 11.


                                        •    Rapid and easy nucleic acid analysis is possible with minimal pretreatment.
                                        •    MALDI-ISD allows simple sequencing of synthetic nucleic acids.                              •    Linear mode (positive ion) MALDI-TOF
                           benefits     •    Benchtop MS can be used with high maintainability and low running cost.                     •    200 Hz solid-state laser, 355 nm
                                                                                                                                         •    Load-lock chamber for fast sample introduction                                                 Excision
                                                                                                                                         •    UV laser-based source cleaning (Pat. US 10340131)                                            Unprotected
                        Methods and Results                                                                                              •    Small footprint/benchtop design                                                                  Oligomer synthesis
                                                                                                                                         •    Quiet operation (<55 dB)
                     Sample   5’-CTGAGACACTGAAGGTAGGA-3’
                     Conc., Volume 100 pmol/µL, 10 µL
                     Preparation  After activation with 1 N hydrochloric acid, approximately 200
                              µL slurry of cation exchange resin (Dowex 50 w 100-200 mesh,
                              Dow chemical) washed with water was added to the Empty
                              microspin column (BioRad), and the solution was removed by
                              gentle centrifugation. Then, 10 µL of the sample was added to
                              the Dowex cation exchange resin column prepared above, and                                                Sample Target Solutions
                              the flow-through was recovered by centrifugation.
                     Mass     1 µL of the collected solution was deposited onto a MALDI target                                          Compatible with the FlexiMass series of microscope slide-format sample targets,                    Purification
                     spectrometry  plate, and the matrix solution (0.5 µL) was overlaid and dried.
                              Measurements were performed in the positive-ion mode.                                                     these slides provide researchers with options depending on their experimental
                     Results  As a result of MS analysis, a singly-charged ion was detected at                                          workflow.
                              m/z 6214.5 (Figure 1).                                                                                    The individually barcoded, single-use FlexiMass-DS slides provide a convenient
                              The ISD spectrum of the nucleic acid was obtained as shown                                                solution for more routine or defined workflows. Ready-to-use, these disposable
                              in Figure 2. The ISD in the positive-ion mode measurement of
                              nucleic acid produces a very simple spectrum because of the                                               targets eliminate the need for cleaning and the risk of carryover. Alternatively, the
                              preferential cleavage producing w-series ions (Figure 3).  Figure 1   MALDI-TOF mass spectrum of  the  synthetic nucleic acid.   reusable stainless steel FlexiMass-SR sample targets provide a cost-effective, longer-
                              Sequence information of the nucleic acid can be easily obtained                                           term solution to sample preparation.
                              by assigning fragment ions of the ISD spectrum.

                                                                                                                                        Automated Source Cleaning
                                                                                                                                        TrueClean                                                                                          Quality Control

                                                                                                                                        To maintain instrument performance over time, the MALDI-8020 features wide-bore ion optics           Characteristic analysis
                                                                                                                                        which minimize the risk of source contamination and provide a robust platform. TrueClean, an
                                                                                                                                        automated source cleaning function, cleans the extraction electrode in-situ quickly within 10 min by
                                                                                                                                        using UV laser without breaking instrument vacuum.                                                 DDS











                             Figure 2   MALDI-ISD mass spectrum with the annotation of w-series ions of the nucleic acid.  Figure 3   Cleavage site by ISD                                                                                   Pharmacokinetics
                                                                                                                                        High Quality with Low-running Cost            Database Management
                                                                                                                                        For improving product performance and the longevity, components   Operating under the control of MALDI Solutions software, the
                                                                                                                                        were carefully selected, which realized a robust platform capable of   software features a centralized, secure Microsoft SQL database which
                                                                                                                                        delivering outstanding performance in a small footprint. Simple design   can be used to store everything from sample lists and acquisition
                                                                                                                                        provides easy maintenance and contribute to maintaining the quality   Parameter Sets to acquired MALDI data. The system is managed by
                                                                                                                                        of analysis over time.                        an administrator and customizable user profiles provide control over
                        Conclusions                                                                                                                                                   access to the database and operation of the instrument. Along with a   Other
                                                                                                                                                                                      full audit trail, the software provides the tools to help achieve 21 CFR
                     By using the benchtop MALDI-TOF MS “MALDI-8020 ” dedicated to positive linear mode, it is possible to easily confirm the molecular
                                                                                                                                                                                      part 11 regulatory compliance.
                     weight and sequence of nucleic acids.


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