Shimadzu Kit for Direct Probe Ionization Mass Spectrometer - DPiMS-8060

Significance of the Topic

Direct Probe Ionization coupled with mass spectrometry (DPiMS) represents a transformative approach in analytical chemistry, enabling rapid analysis of diverse samples without conventional chromatographic separation or intensive preparation. By leveraging Probe Electrospray Ionization (PESI), the method addresses critical needs in forensic toxicology, pharmaceutical quality control and metabolomics, where speed, sensitivity and minimal sample handling are paramount.

Objectives and Overview

This application note introduces the DPiMS-8060 system, detailing its capability to replace an ESI source on standard triple quadrupole instruments. Key goals include demonstrating a simplified workflow for direct analysis, validating quantitative performance against LC–MS/MS benchmarks and illustrating broad usability from drug screening in biological tissues to untargeted metabolomic profiling.

Methodology and Used Instrumentation

• Probe Electrospray Ionization (PESI): Direct sampling via a disposable metal probe touching the sample surface.
• Mass Spectrometer: Triple quadrupole platform (Shimadzu DPiMS-8060) supporting positive‐ion MRM and product‐ion scans over m/z 50–450.
• Software: PESI MS Solution integrated with LabSolutions LCMS for method editing and data acquisition control.
• Key Parameters: Desolvation line at 250 °C, heat block at 50 °C, collision energy ~25 V, scan speed 405 u/s.

Main Results and Discussion

• Forensic Drug Quantitation: MT-45 levels in liver, lung, brain, kidney and heart tissues were measured in under 1 min per event. Results matched LC–MS/MS within 10% discrepancy, while total analysis time dropped from 20 min to 0.5 min per sample.
• Metabolomic Profiling: A panel of 26 primary metabolites (amino acids, organic acids, sugars) in mouse liver showed clear separation between control and toxin-exposed groups via PCA. Taurine emerged as a key discriminator (p < 0.001).
• Carryover Assessment: Alternating analysis of PPGT standard and blanks over multiple cycles revealed negligible residual signals, confirming near‐zero carryover and suitability for unknown or high‐concentration samples.
• Method Transferability: MRM transitions and MS parameters from LC/MS/MS method packages were seamlessly applied, illustrating straightforward method setup via Excel templates and minimal optimization.

Benefits and Practical Applications

• Rapid Screening: Suitable for on-site or high-throughput drug and contaminant detection in food, clinical and forensic samples.
• Minimal Sample Preparation: Direct analysis of biological fluids, tissues and plant extracts reduces consumables and labor.
• Flexibility: Easy swap between PESI and ESI sources on the same instrument allows cross‐validation and data consistency.
• Data Richness: Capable of targeted quantitation and untargeted profiling using identical hardware and software workflows.

Future Trends and Potential Applications

• Automated Probe Handling: Integration of robotics for unattended sampling and higher throughput.
• Ambient Ionization Hybrids: Combining PESI with other surface sampling techniques for expanded analyte coverage.
• AI‐Driven Data Mining: Leveraging machine learning to interpret complex datasets generated in real time.
• Field Deployable MS: Development of portable DPiMS units for environmental monitoring and point‐of‐care diagnostics.

Conclusion

DPiMS-8060 with PESI ionization offers a streamlined, contamination‐resistant platform for direct mass spectrometric analysis. It significantly accelerates workflows, maintains quantitative integrity versus established LC–MS/MS methods and extends applicability from forensic toxicology to metabolomics. The system’s adaptability and low carryover position it as a versatile tool for modern analytical laboratories.

References

• Usui K. et al. (2018) Joint research on direct MSI of MT-45 in tissue sections. Tohoku University Graduate School of Medicine.
• Zaitsu K. et al. (2018) Metabolomic analysis of mouse liver using PESI-MS. Nagoya University Graduate School of Medicine.