LC/MS Tips & Tricks webinars selection in 2024

Update your knowledge about the essential factors of PFAS analysis to support the PFAS National Primary Drinking Water Regulation.

An overview of the various technologies available for MSI, covering different sources and mass spectrometers, from home-built solutions to commercial options.

Tip 1: Preparation and Setup

• Mobile Phase Considerations: Use LC/MS-grade solvents to minimize contamination. Avoid non-volatile salts in the mobile phase as they can interfere with ionization and clog the MS source. If buffers are required, use volatile options (e.g., ammonium acetate or ammonium formate).
• Sample Preparation: Avoid high concentrations of salts, detergents, or other contaminants that suppress ionization.
• Column Selection: Ensure the column is MS-compatible and can handle your solvent composition.

Are you ready to take your LC-TQ troubleshooting skills to the next level?

This webinar will review some of the principles and practices to develop robust RP separation methods showing examples using GLP-1 Agonists.

Tip 2: System Maintenance

• Tuning and Calibration: Regularly calibrate the MS to maintain mass accuracy. Optimize source parameters (e.g., voltage, temperature, gas flows) for your compound class.
• Prevent Contamination: Clean the ion source periodically to remove salt or matrix deposits. Regularly clean or replace parts like the cone, capillary, or skimmer.

High concentration factor in sample preparation with the use of Feed Injection for improved chromatographic performance at high injection volumes and with LC/MS allows lowest possible PFAS detection limits.

6. Separation Science/SCIEX: PFAS Analysis in Food: A Robustness Study in Sensitivity and Stability

Elevate your analytical expertise with advanced techniques and workflows.

Tip 3: Operation

• Ionization Source Optimization: Select the appropriate ionization mode (ESI for polar compounds, APCI for less polar). Adjust nebulizer and desolvation gas flows for optimal droplet formation.
• Gradient Design: Use a suitable gradient profile for efficient separation without excessively long run times. Gradually increase organic content to avoid sudden pressure changes or retention issues.
• Flow Rate Management: Match LC flow rates to the MS inlet specifications (typically 0.2 – 1.0 mL/min). Use a flow splitter if necessary to prevent overloading the MS.

Elevate your analytical expertise with advanced techniques and workflows.

In this series, you will learn the fundamentals of the classical applications of CE.

Tip 4: Troubleshooting

• Signal Problems:
  • Low signal: Check ionization efficiency, tuning parameters, and solvent purity.
  • Signal instability: Verify pump performance, solvent degassing, and source cleanliness.
• Peak Issues:
  • Broad or tailing peaks: Optimize column temperature, flow rate, and injection volume.
  • Missing peaks: Verify sample preparation, gradient, and detection settings.
• Mass Accuracy:
  • Use lock mass or internal calibration to correct drift.
  • Monitor and adjust for environmental factors like temperature and humidity.

This webinar encompasses various sample preparation options for liquid chromatography-mass spectrometry (LC-MS) assays.

Take an in-depth look at when and how to use Excel to increase your productivity.

Tip 5: Data Analysis

• Baseline Noise: Minimize noise by using clean solvents and optimizing the source parameters. Apply appropriate smoothing or baseline correction during data processing.
• Quantitation Tips: Use stable isotope-labeled internal standards when possible. Ensure the linearity of calibration curves across the concentration range.
• Fragmentation Optimization: Adjust collision energy for clear and interpretable fragmentation patterns. Use MS/MS or MRM modes for increased specificity.

Acquire the knowledge needed to optimize source parameters and identify and resolve ionization-related problems.

Learn when to utilize QTRAP functionality to create more selective and sensitive methods.

Collecting UV and MS spectra contemporaneously helps to assure the absence of contaminants with similar chemical properties to your main compounds of interest.

Getting your system ready. LC System Start Up and Shut Down. LC-MS System Start Up and Shut Down. On and Off System Column Storage.

Tip 6: General Best Practices

• Documentation: Maintain detailed logs of instrument settings, mobile phase compositions, and sample information. Record and save method parameters and calibration data.
• Preventive Maintenance: Regularly clean or replace worn parts (e.g., seals, capillaries, and detector components). Follow the manufacturer’s maintenance schedule to prolong system life.
• Training and Knowledge: Stay updated on new techniques, applications, and troubleshooting strategies. Collaborate with colleagues and attend workshops or webinars to enhance your skills.

By applying these tips and tricks, you can improve the reliability, sensitivity, and accuracy of your LC/MS analyses while reducing downtime and troubleshooting efforts.

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