The 2026 edition of the NIST Mass Spectral Library introduces expanded tandem mass spectrometry (MS/MS) reference data and NIST MS Search software version 4.0. While these tools offer powerful capabilities for compound identification and spectral interpretation, practical testing has revealed several software issues that users should be aware of. Some may affect the identification of compounds, the accuracy of imported spectra, or the reliability of library searches.The reported issues involve extracted ion chromatograms (XICs), intensity threshold settings, chromatogram displays, user-created spectral libraries, and software installation. Additional difficulties can arise when connecting NIST MS Search with MS Interpreter.The observations, documented during testing in August 2026, may depend on specific datasets, software configurations, or installation environments. They should therefore be treated as reported issues rather than defects necessarily affecting every NIST26 installation.<h4>1. Background Filtering May Remove Useful XIC Identifications</h4>One of the reported issues concerns the Background setting in the XIC analysis workflow. In certain datasets, applying background filtering can remove peaks that may contain useful identification information, even when they exhibit high relative abundance and strong library matching scores.The affected peaks typically have several characteristics:<ul><li>They are represented by a single scan.</li><li>Their chromatographic peak width is recorded as zero.</li><li>The software assigns them an XIC value of 0.</li><li>They cannot be processed by XIC Analyzer because they do not meet its processing criteria.</li></ul>Despite these limitations, some peaks may still provide potentially valuable analytical information. In one example, a peak assigned XIC = 0 exhibited a relative abundance of 100% and a high library matching score.The problem is that applying background filtering can exclude these peaks from both the identification results and abundance calculations.To avoid overlooking potentially relevant compounds, users should review results with background filtering disabled or the Background option set to "Any". Peaks with XIC = 0 can be sorted by abundance and examined individually using the butterfly plot for spectral comparison.Any potentially significant identification should be verified against the original vendor data, particularly because single-scan peaks may also reflect acquisition conditions or analytical artifacts.<h4>2. Intensity Threshold Settings Can Cause Loss of Accurate-Mass Information</h4>Another important issue involves the Intensity Threshold option in the Spectrum Import Options window.During testing, enabling an intensity threshold when importing vendor-generated MS/MS spectra caused high-resolution mass spectra to be converted to nominal-mass spectra.Instead of preserving fragment ion m/z values with four decimal places, the imported spectra displayed integer m/z values.This behavior is particularly problematic for high-resolution MS/MS applications, where accurate mass measurements contribute to elemental composition assignment and compound identification.The Intensity Threshold function could otherwise be useful for reducing electronic noise, including noise observed in Agilent MS/MS spectra.Recommended workaround: Avoid applying the Intensity Threshold option during spectrum import when accurate-mass information must be preserved. Until the behavior is resolved, noise reduction should be performed using independently validated processing procedures.<h4>3. Chromatogram Display Precision Depends on Spectrum Import Settings</h4>A related issue affects the Chromatogram tab in NIST MS Search.The number of decimal places displayed for m/z values in the chromatogram window is determined by the settings selected in Spectrum Import Options. These settings are not independently controlled.For example, when the import precision is set to zero decimal places for low-resolution spectra, the chromatogram display also shows truncated m/z values.Importantly, this behavior does not affect the accurate-mass deconvolution and library-search results table.However, it can affect spectra transferred from the chromatogram window to the library-search function.Users should therefore distinguish between the accurate-mass information retained in the deconvolution results and the values displayed or transferred through the chromatogram interface.Before initiating additional library searches from the chromatogram window, it is advisable to verify that the displayed m/z precision is appropriate for the analytical task.<h4>4. Problems with Hybrid and Precursor-Independent Searches in User Libraries</h4>Another issue concerns search functions applied to user-created MS/MS spectral libraries.After adding high-resolution MS/MS spectra to a user library, the following search modes may fail to operate correctly:<ul><li>HiRes NoPrecursor identity search</li><li>Similarity Hybrid MS/MS search</li></ul>In the reported tests, attempting to perform a Hybrid MS/MS search could cause the software to crash with error code 0005.A practical workaround involves rebuilding the affected user library using Lib2NIST:<ol><li>Export the library spectra as ASCII <code>.msp</code> files, together with the associated <code>.mol</code> structure files.</li><li>Reimport the exported data using Lib2NIST.</li><li>Generate a new library in the NIST library format.</li><li>Verify that the required search functions operate correctly.</li></ol>As a temporary alternative, the EI Normal search mode may provide useful results resembling those obtained with HiRes NoPrecursor searches, although it should not be considered an equivalent replacement.HiRes NoPrecursor searching may also work when the presearch function is disabled, but this can substantially increase search times.Until the issue is resolved, users should avoid running the affected Hybrid MS/MS search on problematic user libraries.<h4>5. Installation and Uninstallation May Modify the Windows win.ini File</h4>Potential configuration problems have also been observed when installing the NIST Tandem demonstration software on computers with an earlier NIST version already installed.In particular, the installation process may modify the Windows configuration file:<code>C:\Windows\win.ini</code>During testing involving NIST23 and the NIST Tandem demo, additional configuration entries were introduced. Some remained after the demonstration software was uninstalled.These residual entries could potentially interfere with the configuration of existing or subsequently installed NIST software, although their impact has not been established for every system.Before installing the demonstration version, users should:<ul><li>Back up the original <code>win.ini</code> file.</li><li>Record the existing NIST software configuration.</li><li>Check for residual demonstration-related entries after uninstallation.</li><li>Ensure that any restored configuration file retains the <code>.ini</code> extension.</li></ul>Because <code>win.ini</code> is located in a protected Windows directory, modifications should be performed only by authorized users, preferably with assistance from an IT administrator.<h4>6. MS Interpreter: Resolving Registration and Connection Problems</h4>Difficulties opening NIST MS Interpreter may be related to its registration within Windows rather than an actual defect in NIST26.MS Interpreter is a separate application, executed as <code>MSPCALC.EXE</code>, that supports the interpretation of mass spectra using chemical structures, fragment formulas, and fragmentation mechanisms.Communication between NIST MS Search and MS Interpreter relies on Windows OLE/COM registration. Problems may arise when an earlier version remains registered or when the software has been moved, replaced, or incorrectly installed.NIST provides the MSINTREG.EXE registration utility to reconnect MS Interpreter to MS Search.The recommended procedure involves:<ol><li>Closing NIST MS Search.</li><li>Placing <code>MSINTREG.EXE</code> in the folder containing <code>MSPCALC.EXE</code>, <code>Frag32.dll</code>, and <code>Qual.dll</code>.</li><li>Running the registration utility with the required administrative privileges.</li><li>Restarting NIST MS Search and testing the connection using Send To → MS Interpreter.</li></ol>In some cases, unregistering the previous installation using UnregServer and registering the correct version using RegServer may help.Users working on company-managed or university computers may need assistance from their IT departments.<h4>Practical Recommendations for NIST26 Users</h4>These reported issues highlight the importance of checking software settings and validating results when working with tandem mass spectrometry data.Particular attention should be given to preserving accurate-mass information during import, reviewing signals excluded by XIC filtering, and verifying the functionality of custom spectral libraries.Maintaining backups of user libraries and software configuration files can also help prevent disruptions when installing or updating NIST software.Although NIST26 provides extensive capabilities for MS/MS data interpretation, understanding these potential limitations and applying appropriate workarounds can help laboratories obtain more reliable identification results and maintain efficient analytical workflows.The availability and timing of any future software corrections should be verified against the specific NIST release and software build in use.

Current Bugs in NIST26 MS/MS (Tandem) Software

In modern analytical laboratories, productivity is no longer just about speed—it is about maximizing data output, minimizing downtime, and extracting more information from every sample. <a target="_blank" rel="noopener noreferrer" href="https://labrulez.com/en-us/lcms/products?category=37&amp;manufacturerItems=3&amp;search=Vanquish">Thermo Scientific’s Vanquish platform</a> represents a major step forward in high-throughput liquid chromatography (LC), combining advanced hardware, intelligent automation, and flexible workflows.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Thermo_Fisher_Scientific_Unlocking_High_Throughput_Potential_in_Liquid_Chromatography_With_Vanquish_Systems_32909db01a.jpg" alt="Thermo Fisher Scientific: Unlocking High-Throughput Potential in Liquid Chromatography With Vanquish Systems" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_Thermo_Fisher_Scientific_Unlocking_High_Throughput_Potential_in_Liquid_Chromatography_With_Vanquish_Systems_32909db01a.jpg 245w," sizes="100vw" width="1024" height="574">This article explores how high-throughput capabilities are achieved across the Vanquish ecosystem, with a focus on the Vanquish Duo UHPLC, autosampler capacity, Vanquish Sample Hub (Charger module), and Transcend systems.<h3>The evolution of high-throughput LC</h3>Traditional LC systems often face bottlenecks in sample handling, equilibration time, and instrument utilization. The Vanquish platform addresses these limitations through:<ul><li>Parallelization of workflows</li><li>Automation of sample handling</li><li>Expansion of unattended operation</li><li>Integration with LC-MS and multiplexing strategies</li></ul>Together, these innovations allow laboratories to significantly increase throughput without compromising data quality or robustness.<h3>Vanquish Duo UHPLC: parallelization for maximum productivity</h3>At the heart of high-throughput innovation is the <a target="_blank" rel="noopener noreferrer" href="https://labrulez.com/en-us/all/products/742">Vanquish Duo UHPLC system</a>, designed to effectively double productivity within a single instrument footprint.Key high-throughput features:<ul><li>Dual independent flow paths: Two LC channels operate simultaneously, enabling parallel analysis</li><li>Simultaneous workflows: Run identical methods for higher throughput or different methods for deeper sample insights</li><li>Dual split sampler: Two injection devices allow independent control of each channel</li><li>Reduced cost per sample: Increased output without additional bench space or instrumentation</li></ul>This dual-channel capability is particularly powerful in pharmaceutical and biopharmaceutical environments, where both speed and comprehensive characterization are critical. Watch this recent <a target="_blank" rel="noopener noreferrer" href="https://labrulez.com/en-us/all/webinar/5948">short webinar</a> for a more detailed overview of the Vanquish Duo.<h3>Autosampler capacity: scaling sample throughput</h3>High-throughput LC is only as effective as its sample handling system. <a target="_blank" rel="noopener noreferrer" href="https://www.thermofisher.com/content/lifetech/global/en/home/industrial/chromatography/liquid-chromatography-lc/hplc-uhplc-components/hplc-uhplc-autosamplers-injectors.html">Vanquish autosamplers</a> are engineered to ensure both precision and capacity.Highlights:<ul><li>High sample capacity: Standard configurations can accommodate hundreds of vials (e.g., ~200+ samples depending on setup)</li><li>Exceptional injection precision: Ensures reproducibility even in large batch analyses</li><li>Wide format compatibility: Supports vials, well plates, and various volumes for diverse workflows</li></ul>For high-throughput labs, this means fewer interruptions, consistent performance, and confidence in large-scale studies.<h3>Vanquish sample hub (charger module): automation for unattended operation</h3>To further extend throughput, the <a target="_blank" rel="noopener noreferrer" href="https://labrulez.com/en-us/all/products/2455">Vanquish Sample Hub</a> (also known as the Charger module) introduces robotic automation into the LC workflow.Key advantages:<ul><li>Automated sample loading: Reduces manual intervention and operator workload</li><li>Expanded capacity: Supports up to 20 additional well plates, dramatically increasing sample volume</li><li>Extended unattended runs: Ideal for overnight or weekend operation</li></ul>This capability transforms LC systems into continuous productivity platforms, enabling labs to process thousands of samples with minimal supervision.<h3>Transcend Systems: Online Sample Preparation for True Throughput Gains</h3>While Vanquish Duo and autosamplers enhance analytical throughput, <a target="_blank" rel="noopener noreferrer" href="https://labrulez.com/en-us/all/products/2241">Transcend systems</a> take it further by integrating online sample preparation with LC-MS.<h3>Throughput benefits of Transcend:</h3><ul><li>Online SPE (Solid Phase Extraction) reduces manual prep time</li><li>Parallel sample cleanup and analysis improves instrument utilization</li><li>Reduced cycle times by eliminating offline preparation steps</li></ul>In high-throughput bioanalysis and clinical research, Transcend systems enable end-to-end workflow acceleration, from raw sample to final data.<h3>Bringing it all together: a holistic high-throughput workflow</h3>The real power of the Vanquish platform lies in combining these technologies:<h5>Component &nbsp;/ &nbsp;Contribution to throughput</h5><ul><li>Vanquish Duo UHPLC: Parallel LC analysis (2x throughput)</li><li>Autosampler: High-capacity, precise sample injection</li><li>Sample Hub (Charger): Automated, extended unattended operation</li><li>Transcend Systems: Integrated online sample preparation</li></ul>Together, they create a fully optimized LC ecosystem where:<ul><li>Sample queues are larger</li><li>Downtime is minimized</li><li>Data output per unit time is maximized</li></ul><h3>Conclusion: Redefining Productivity in LC</h3>High-throughput liquid chromatography is no longer just about faster runs—it is about smarter system design. The Vanquish platform achieves this through:<ul><li>Parallel processing (Vanquish Duo)</li><li>Scalable sample handling (autosamplers and Sample Hub)</li><li>Workflow automation (Transcend systems)</li></ul>By integrating these elements, laboratories can achieve unprecedented efficiency, flexibility, and analytical depth, positioning themselves to meet the growing demands of modern science.<blockquote>Visit us on&nbsp;<a target="_blank" rel="noopener noreferrer" href="https://www.linkedin.com/showcase/72003132/admin/dashboard/">LinkedIn:</a>&nbsp;#UHPLC, #throughput, #productivity</blockquote>

Unlocking High-Throughput Potential in Liquid Chromatography With Vanquish Systems

Sample dilution is a routine part of elemental analysis—but it can also become a significant source of manual work, variability, and laboratory bottlenecks. When samples fall outside the calibration range, contain high particulate loads, or require different dilution factors, analysts may need to stop a sequence, prepare new dilutions, and repeat measurements.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/Thermo_Fisher_Scientific_Reducing_Errors_and_Increasing_Throughput_in_ICP_MS_and_ICP_OES_with_Automated_Dilution_61d41669d9.webp" alt="Thermo Fisher Scientific: Reducing Errors and Increasing Throughput in ICP-MS and ICP-OES with Automated Dilution" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_Thermo_Fisher_Scientific_Reducing_Errors_and_Increasing_Throughput_in_ICP_MS_and_ICP_OES_with_Automated_Dilution_61d41669d9.webp 245w," sizes="100vw" width="1024" height="512">The <a target="_blank" rel="noopener noreferrer" href="https://labrulez.com/en-us/all/products/2637">prepFAST 3 autodilution system</a> is designed to bring dilution directly into the analytical workflow, combining high-throughput sample introduction with automated dilution for <a target="_blank" rel="noopener noreferrer" href="https://labrulez.com/en-us/icpms/products?category=232&amp;manufacturerItems=3&amp;search=icap">ICP-MS</a> and <a target="_blank" rel="noopener noreferrer" href="https://labrulez.com/en-us/icpms/products?category=227&amp;manufacturerItems=3">ICP-OES</a> analysis. The system supports both undiluted FAST analysis and diluted sample analysis, allowing laboratories to handle different sample requirements within a single automated workflow.<h3>From manual dilution to an automated workflow</h3>With prepFAST 3, samples can either be introduced undiluted or diluted automatically before analysis. For undiluted samples, the system loads the sample and injects it for analysis using the FAST workflow. When a dilution factor greater than one is required, the sample is loaded into the dilution line, diluted by syringe into the sample line, and then injected for analysis.Integration with <a target="_blank" rel="noopener noreferrer" href="https://labrulez.com/en-us/all/products/1489">Thermo Scientific Qtegra Intelligent Scientific Data Solution Software</a> extends this automation into the analytical method itself. Users can prescribe dilution factors for standards and samples directly in the sample list.More importantly, dilution can respond to analytical results. If an analyte exceeds method-defined quality-control levels, the sample can be automatically returned to the sample list and reanalyzed at a higher dilution factor until its concentration falls within the specified range.This turns dilution from a separate sample-preparation step into part of the analytical decision-making process.<h3>Intelligent QC-driven dilution</h3>Automation becomes particularly valuable when unexpected samples enter a sequence. Instead of requiring an analyst to identify an over-range result, prepare another dilution, and restart the analysis, Qtegra and prepFAST 3 can trigger reanalysis based on user-defined criteria.The workflow can also respond to internal-standard recovery. If internal-standard recovery fails, prepFAST can rerun the sample using a prescribed dilution and continue doing so up to a user-defined maximum. Likewise, when an elemental concentration exceeds the calibration range, the system can trigger reanalysis through the Intelligent Dilution functionality, with the reanalysis limits and target range defined by the user.The result is an analytical workflow designed to reduce manual intervention while keeping dilution decisions tied to predefined method and QC criteria.<h3>Keeping challenging samples moving</h3>Automation is only useful if the sample introduction system can keep running. High-particulate, unfiltered, and fiber-containing samples can present a particular challenge because particles may clog valves or nebulizers.The prepFAST 3 FilterProbe addresses this at the autosampler probe. An inline CTFE filter traps larger particles and fibers before they reach downstream components. While the sample is being analyzed, the filter is rapidly backflushed at the waste station using a syringe-driven process, preparing the system for the next sample. As illustrated by the brine pipeline sludge example on page 12, the concept is intended to extend automation even to highly challenging, particulate-rich samples. The presentation notes that this approach can help minimize valve and nebulizer maintenance while maintaining high throughput.<h3>Knowing whether the sample actually loaded</h3>Another potential source of analytical problems is incomplete sample loading. SampleSense3 adds sensor-based monitoring to the workflow. It detects samples, accounts for viscosity by adjusting loading timing, and can detect and log incomplete loading caused by conditions such as a clogged filter, capped vial, or empty vial.That capability helps shift the workflow from simply automating physical sample movement toward monitoring whether the automated process is functioning as intended.<h3>Designed around uptime and usability</h3>prepFAST 3 also introduces hardware features intended to simplify routine operation and maintenance. Multiposition Magnetic SnapValves can be removed without tools and use a two-valve sampling architecture for FAST and prepFAST operations.High-purity quartz syringes are used for dilution and sample carrier delivery, with 6 mL and 3 mL syringe configurations respectively. The system also incorporates a hinged, single-screw mounting design intended to simplify syringe maintenance and replacement.Together with features such as FilterProbe, SampleSense3 and a shortened probe configuration, these elements are designed around a practical laboratory objective: keeping automated analytical sequences running with less intervention.<h3>More analysis, less sample handling</h3>For laboratories processing large numbers of samples by ICP-MS or ICP-OES, improving productivity does not necessarily mean making the measurement itself faster. Significant gains can come from reducing the manual steps surrounding each measurement.By combining high-throughput sample introduction, prescribed and QC-driven autodilution, automated reanalysis, particulate management, and sample-loading monitoring, prepFAST 3 moves several traditionally manual activities into the analytical sequence itself. The objective is straightforward: rapidly analyze both diluted and undiluted samples while improving the user experience and maintaining a compact laboratory footprint.For elemental-analysis laboratories looking to reduce repetitive sample preparation and increase unattended operation, automated dilution offers a way to make the workflow—not just the instrument—more efficient.<h5>Acknowledgement</h5>I would like to thank Torben Stichel, Joerg Axthelm and Sebastian Voelker Field Applications Scientist, Germany, Trace Elemental Analysis and for the support on this blog and the webinars<h3>References:</h3><ul><li>Watch this webinar on demand in German language: <a target="_blank" rel="noopener noreferrer" href="https://event.on24.com/wcc/r/5179292/AE4C576B6A54D1AC182F7F77573D380F">Fehler reduzieren, Durchsatz steigern: Autoverdünnung mit PrepFast am ICP-MS</a></li><li>Product Spotlight: <a target="_blank" rel="noopener noreferrer" href="https://labrulez.com/pdf/sl_004425_intelligent_autodilution_esi_prepfast3_sl004425_en_0d3490e91e.pdf">Qtegra Intelligent Scientific Data Solution Software</a></li><li>Sign up for our webinars live and on demand</li></ul><h5>English</h5><ul><li><a target="_blank" rel="noopener noreferrer" href="https://labrulez.com/en-us/all/webinar/5795">Lunch and Learn Tips and Tricks Series: Qtegra Part 1</a></li><li><a target="_blank" rel="noopener noreferrer" href="https://labrulez.com/en-us/all/webinar/5976">Lunch and Learn Tips and Tricks Series: Qtegra Part 2</a></li><li><a target="_blank" rel="noopener noreferrer" href="https://labrulez.com/en-us/all/webinar/5977">Lunch and Learn Tips and Tricks Series: Trace Elemental Analysis (ICP-OES &amp; ICP-MS)</a></li><li><a target="_blank" rel="noopener noreferrer" href="https://labrulez.com/en-us/all/webinar/5978">Trace Elemental Analysis: Ask the Expert</a></li></ul><h5>Deutsch</h5><ul><li>19. März 2026 <a target="_blank" rel="noopener noreferrer" href="https://event.on24.com/wcc/r/5179134/393E071E3B501943730958BA6203F477">Interne Standards in der ICP-OES: Ein Praxisguide für zuverlässige Qualitätssicherung im Labor</a></li><li>18. Juni 2026 <a target="_blank" rel="noopener noreferrer" href="https://event.on24.com/wcc/r/5179292/AE4C576B6A54D1AC182F7F77573D380F">Fehler reduzieren, Durchsatz steigern: Autoverdünnung mit PrepFast am ICP-MS</a></li><li>17. September 2026 <a target="_blank" rel="noopener noreferrer" href="https://event.on24.com/wcc/r/5179423/B5019C560431BADCA2A76E54E4EFE56F">ICP-OES smarter nutzen: Probendurchsatz erhöhen, Ressourcen sparen</a></li><li>17. Dezember 2026 <a target="_blank" rel="noopener noreferrer" href="https://event.on24.com/wcc/r/5179530/94EEDD1F56138F5EEE2AF24E29E6C12A">Qtegra ISDS Software Unlocked – Live im Expertengespräch</a></li></ul><blockquote>Visit us on&nbsp;<a target="_blank" rel="noopener noreferrer" href="https://www.linkedin.com/showcase/chromatography-&amp;-mass-spectrometry/posts/?feedView=all">LinkedIn:</a>&nbsp;#ICPMS #ICPOES #AutomatedDilution #LabAutomation</blockquote>

Reducing Errors and Increasing Throughput in ICP-MS and ICP-OES with Automated Dilution

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Agilent PAL3 SPME + SPME ARROW Condition Station, G7380-60001 (Refurbished)

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CTC PAL RTC 120 Automated Sample Preparation System, G7370-66669 (New)

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