Before you start diagnosing the DropDetection functionality/performance, please turn off the instrument, open the lid, and pull out the source tray. 

1. Clean the bottom of the source tray (i.e., DropDetection board) using Kimwipes and 70% ethanol. Let it dry for 3-5 minutes. Clean each DropDetection opening from the top using a lint-free cotton swab soaked with 70% Ethanol. Change swab if a significant amount of dust/debris is observed. Let the ethanol dry and push back the tray into the machine. 

2. Create a protocol to dispense 500 nL deionized water from each source wells to each target well (A1 to A1, B1 to B1, etc.). 

Concern regarding false positives result (no liquid dispensed to target, but software detects droplets): 

Test and Validation

1. Please use a new, unused source place to dispense “liquid” to the target.

It must show red result in all 96 positions. 

Concern regarding false negatives result (liquid dispensed to target, but software does not detect droplets): 

Test and Validation

1. Please fill in each source well with 10 or 20 µL (i.e., more than enough) deionized water to prevent having too little liquid in the wells and to be able to repeat the run/test three to five times. Make sure you do not have air bubbles inside the wells. 

2. Execute the protocol and repeat it three or more times, if necessary. After each run if you get bad result and have suspicions on specific wells (e.g., they are clogged, contaminated), please swap this with wells which give you good results from the previous tests. 

Acceptance criteria: number of droplets not detected in random positions not greater than 1%. E.g., for 500 nL = 11 droplets in each target X 96 wells position = overall 1056 drops; not more than 10 droplets overall are not detected). 

Dispense deionized water on transparent, plastic, foil-sealed 1536 target well plate from A1 (top left) and H12 (bottom right), to center, and four corners on the target. Dispense “different” liquid (e.g., water, water 1) from same Liquid Class [VSCY 0.95 (H2O)] and assign them to A1 and H12 (see figure above). 

From the result, we could see if the target tray position is shifted to the left/right or even tilted in certain direction. If all droplets are dispensed consistently to the left, you must adjust this to the left, and vice versa. 

Make sure the source wells do not have any shooting angle. You can check this by flipping the wells 180°, repeating the dispense run, and see whether the droplets are now dispensed to the other side/direction. 

Change the Target Position

Please go to general settings, click on “Show Advanced Settings,” enter the password "Dispendix," click on “Move To Home," and then try to adjust the target tray position. Click "Ok" and please restart Aassay Studio. Check again if the positioning is now in spec. 

This means that there is a poor seal between the well and the rubber of the dispense head or that there is no well in the source position used. 

Please make sure: 

1. Source wells are fully in place. Make sure source plate with enough wells used during the protocol. 
2. Dispense head channel and source wells are fully aligned (X/Y direction). Contact DISPENDIX Support to resolve. 
3. Dispense head is sitting at a correct distance to the source wells: around 1 mm distance, we use 0.8 mm plastic card with smooth surfaces to check this by sliding it between head rubber and source plate (filled with wells). Make sure, you have similar distance at front and back, no tilting is allowed. Please contact DISPENDIX Support to resolve. 
4. Head rubber not damaged, cut, or ripped off. Please contact DISPENDIX Support. 
5. The head valves are not “warm." Occasionally, it happens when the device is just started. Mostly it happens when the device or dispense head has not been used for a while. With the software version 2.0 above, we have the pre-conditioning feature, which always warms up the valves at the beginning, when software is started. Please update the software, in case you have still the version 1.10 or older. 
6. Head sealing is not broken or leaking. You should not hear any whistling sound coming out from the head or a specific channel when the device is not dispensing. Please contact DISPENDIX Support. 

If the source or target trays do not eject when you press the buttons, it is likely because the software hasn't been launched yet.

Ensure that you start Assay Studio first. If the device is turned off, you can open the doors manually.

To fully activate the device, first switch on the main power, then press the on/off button located at the front.

If an error message appears indicating a communication issue with the distribution board, please ensure the following:

• Launch the software 10-15 seconds after the device has been powered on.
• Verify that all cables, particularly the one connecting to the surface tablet, are securely plugged in.
• If the instrument fails to start despite the on/off button being illuminated green, check that the lid was not open when the device was powered on.

It's possible that the lid was open when the instrument was powered on. Please close the lid, switch off the main power, and then toggle the on/off switch again.

• Ensure the air pressure connection is secure and the air supply capacity is within the range of 3-10 bar (40-145 psi). 
• Check the Source Plate and replace any missing source wells. 
• Confirm that the dispense head is correctly positioned on the source wells. If you encounter issues, reach out to DISPENDIX Support for assistance. 

Incorrect or missing liquid class settings in the software: Please assign or create the appropriate liquid class for the selected protocol.

Barcode reader malfunction: Ensure the barcode reader is activated. To activate, access the advanced settings with a password and navigate to Menu > Settings > Device Settings > General Settings to enable the barcode reader usability option.

Improper sensor alignment: If the sensor is not positioned correctly, please contact DISPENDIX Support for assistance.