Back to the laboratory, the first thing is of course to turn on the instrument, but the instrument that has been resting for such a long time may have a "post-holiday syndrome" like you, and it might be awkward, so how to turn on your instrument correctly?
- Prepare the mobile phase according to the experiment, prepare the pump head cleaning solution 10% methanol aqueous solution, and prepare the autosampler needle washing solution 10% methanol aqueous solution;
- Turn on the power switches of the pump, autosampler, column thermostat, and detector in turn;
- Check if there are any bubbles inside the infusion tube, if there are, they should be discharged through the drain valve in time
- Turn on the computer, double-click the SmartLab 2.0 icon on the desktop to enter the software;
- The pump discharges bubbles (open the Purge valve and discharge the bubbles separately for each channel), remember to close the Purge valve after the bubbles are discharged;
- After starting up, remove the cinematographic column, connect the entire pipeline, and clean the system with mobile phase for 30 minutes.
- Connect the chromatographic column, set the ratio and flow rate of the mobile phase, remember that the flow rate setting principle is from low to high, first set the flow rate of 0.2ml/min, and run at this flow rate for more than 30 minutes, and slowly increase the flow rate until it reaches the final use Flow rate, balance system; (If buffer salts are used in the mobile phase, please rinse the flow path with 10% methanol or acetonitrile water for 15 minutes, and then change to the ratio of mobile phase analysis);
- Set the column oven temperature
- Cleaning the autosampler: click the injector flush button to repeatedly flush the injector
- Turn on the deuterium lamp or tungsten lamp, set the detection wavelength, acquisition frequency and time constant; (it is recommended to turn on the pump for 5 minutes before lighting)
#02.Common precautions for liquid chromatography
- The liquid storage bottle needs to be thoroughly cleaned before use to ensure cleanliness, otherwise it may cause system blockage
- The pressure gradually changes (increases or decreases) for a period of time after starting up. This is often because the mobile phase has not been well balanced in the chromatographic column and the oven temperature has not been constant. These are not instrumental issues, as long as you balance it for a while, it will be stable. If you are using a gradient program, since the ratio of the mobile phase is changing, the pressure will follow the change.
- No pressure or instantaneous pressure change after starting up (>3MPa): The reason is nothing more than the following four conditions: (1) There is air bubbles; (2) Leaking; (3) Check valve is not good; (4) Pump working phase is incorrect ; (5) The sinker is blocked, which can be eliminated one by one.