This is a time critical step.
Press the Dispense button multiple times in a row to assess the dispenser performance with sample.
The dispense pattern will generally look different than the pattern with water. It will also sometimes be less consistent or less vertical when working with sample. As long as the sample is consistently dispensing and generally vertical, even if the pattern changes somewhat between dispenses, it is fine. A less stringent criteria should be applied when dispensing samples.
If necessary, use the Troubleshooting tab to diagnose and address issues with the dispenser.
- Changes to Advanced options such as Amplitude and Increase / Decrease Dispenser Back Pressure can be used to compensate for a more or less viscous sample/buffer solution.
When changing Amplitude, care should be taken to make changes in a step-wise fashion (ex step: 50) to ensure a bubble is not accidentally created and encapsulated at the dispenser tip. - With difficult-to-dispense samples, the Wipe Dispenser and Multi-Wipe Dispenser options can be used to remove debris or liquid from the tip of the dispenser.
- The Dip Dispenser option can be used to dip the dispenser into the water well of the wash station to dissolve/remove any films that might have formed at the dispenser tip. After a Dip Dispenser action, the Mini-Prime action is automatically performed and pushes a small amount (0.5 µL) of sample out of the dispenser tip.
Once the dispenser is consistently dispensing the sample, press Continue. A grid will be picked up.
If these do not address the issues and an appropriate dispense pattern cannot be achieved, use the Finish Session button on the main toolbar to end the current freezing session and clean the dispenser. Note: This will cause the sample to be lost.