Q: I am thinking of switching to a column with a smaller inner diameter. In addition to changing the column, is there anything else that I need to consider?
When using a semi-micro column, in order to suppress extra-column dispersion, use flow channel tubing and a detector cell of small dimensions, in accordance with the inner diameter of the column. Furthermore, in accordance with the overall size reduction of the flow channels, use a small gradient mixer. With regard to the auto-injector too, consider the inner diameter of the tubing in parts that the sample passes through. Also, in comparison with conventional LC, greater solvent delivery stability, in the form flow rate accuracy and precision at low flow rates, is required of the solvent delivery unit, and greater injection reproducibility in microinjection is required of the autosampler. Details: Switching to Semi-Micro.