While it’s easy to think of the Echo® MS system as an ultrafast LC system in front of the SCIEX Triple Quad 6500+ mass spectrometer, the system operates on fundamentally different principles. For this reason, it requires different routine maintenance to keep it running at its best. The component of the Echo® MS system most likely to experience premature wear is the source electrode. Here are some tips for maximizing its lifetime:
- Sample matrix that is not soluble in your carrier solvent will precipitate, and over time this can clog the electrode. If you observe buildup or blockage on the electrode, clean the source electrode end in water to dissolve the matrix that was insoluble in the carrier solvent and precipitated onto the electrode. To clean the electrode, remove the transfer line electrode assembly and connect it to a high-flow LC pump, if available, for 10–15 minutes; otherwise, soak the electrode in water for 30 minutes. This is more often needed when running high salt or plasma samples.
- Do not use ISV values greater than 5000 V. Sustained use of the electrode at high voltages will reduce its lifetime.
- Keep the temperature below 500°C. For methanol, at the typical optimized flow rates for the Echo® MS system, the temperature generally does not need to exceed 300°C. Sustained use of the electrode with higher temperatures will reduce its lifetime.
- Set the MS to standby after use so the source conditions are not applied when there is no activity on the system. Because Gas 1 shuts off in standby, the solvent delivery pump is stopped and solvent is not pulled through the OPI.