Technical Overview and Maintenance Guide for Waters SYNAPT G2-Si Mass Spectrometer

1. Instrument Overview

The Waters SYNAPT G2-Si is a high-performance quadrupole-time-of-flight (Q-TOF) tandem mass spectrometer featuring Triwave® ion mobility separation. It is widely used in proteomics, metabolomics, environmental contaminant analysis, and small-molecule structural elucidation in complex matrices. Its core advantages include:

• Multidimensional separation: Mass-to-charge (m/z), ion mobility (CCS), and MS/MS fragments
• High resolution: >40,000 FWHM
• Ultrahigh sensitivity: Sub-femtogram detection limits

2. Core Technologies & Configurations

2.1 Key Modules

• Ion Sources: Supports ESI (electrospray ionization) and APCI (atmospheric pressure chemical ionization) for diverse sample types.
• Triwave® Ion Mobility: Separates ions based on collision cross-section (CCS), enhancing peak capacity.
• StepWave™ Ion Optics: Maximizes ion transmission while reducing noise (S/N improvement >10x).
• Tof Reflector: Delivers <2 ppm mass accuracy for precise compound identification.

2.2 Software Platform

• UNIFI® Scientific Information System: Integrates data acquisition, processing, and database searching (targeted/non-targeted workflows).
• Dynamic Range Enhancement (DRE): Enables **>5 orders of magnitude** dynamic range.

3. Routine Maintenance Guide

3.1 Daily Maintenance

• Ion Source Cleaning:
  • Disassemble ESI/APCI probe, sonicate in isopropanol (10 min), rinse with HPLC-grade water, and dry with N₂.
  • Check capillary for clogging; flush with MeOH/H₂O (1:1) if needed.
• Vacuum System Check:
  • Confirm mechanical pump oil level (replace if cloudy).
  • Verify turbopump speed (>90% rated) and TOF pressure (<1×10⁻⁶ mBar).

3.2 Weekly Tasks

• Mass Calibration:
  • Use NaCsI or leucine enkephalin calibrant; ensure <2 ppm mass error via UNIFI.
• Gas System Inspection:
  • Maintain N₂ pressure (7–10 psi for ESI); replace desiccant if color-indicator turns pink.

3.3 Monthly Maintenance

• Ion Lens Cleaning:
  • Soak and sonicate ion guides in MeOH/H₂O (1:1); avoid scratching surfaces.
• Pump Oil Replacement:
  • Change every 500 hours (use Edwards E2M28 oil for rotary vane pumps).

3.4 Annual Professional Service

• Schedule turbopump maintenance, high-vacuum seal replacement, and full-system performance validation with Waters engineers.

4. Troubleshooting Common Issues

5. Critical Best Practices

• Avoid frequent power cycles: Allow **>4 hours** for turbopump cooldown to prevent bearing damage.
• Use LC-MS grade solvents only: Minimize salt/particulate contamination.
• Back up method files: Export instrument parameters via UNIFI to external storage.

6. Conclusion

Proactive maintenance of the SYNAPT G2-Si—particularly for the ion source and vacuum system—ensures long-term reliability and data integrity. Laboratories should:
✓ Maintain a detailed service log
✓ Follow Waters-recommended intervals
✓ Engage technical support for complex issues

Appendix:

• Recommended consumables: Waters P/N 700004690 (ESI probe), 700003208 (capillary)
• Emergency support: Waters Technical Service Hotline (400-820-2676 in China)

Note: Adjust maintenance frequency based on usage intensity and lab environment.

Key Performance Metrics:
▶ 99.7% uptime with scheduled maintenance
▶ <1% CV in retention time reproducibility
▶ 5+ years typical service life under optimal care

(Compliant with GMP and 21 CFR Part 11 requirements)

Why This Matters:

• Pharma Labs: Meet FDA data integrity standards
• Academic Users: Protect years of calibration data
• CROs: Minimize downtime in high-throughput workflows