Methods, devices, and apparatus for washing samples on array plates

A method for washing a sample, the method comprising:

• obtaining an array plate that includes an array of hydrophilic areas surrounded by one or more hydrophobic areas, wherein:
• a respective solution containing a sample is located on a respective hydrophilic area of the array of hydrophilic areas;
• the respective hydrophilic area includes one or more indentations from a respective surrounding hydrophobic area of the one or more hydrophobic areas;
• and
• the respective hydrophilic area includes a first indented surface that is offset by a predefined height from a reference surface defined by the respective surrounding hydrophobic area;
• placing a dispenser nozzle above the respective hydrophilic area while a nozzle tip of the dispenser nozzle is in contact with the respective solution;
• dispensing a wash liquid with the dispenser nozzle to the respective solution while the nozzle tip of the dispenser nozzle is in contact with the respective solution;
• placing an aspirator nozzle above the respective hydrophilic area at least 100 μm from the first indented surface while a nozzle tip of the aspirator nozzle is immersed in a mixture of the wash liquid and the respective solution;
• and
• aspirating a portion of the mixture with the aspirator nozzle while the aspirator nozzle is located at least 100 μm from the first indented surface and while the nozzle tip of the aspirator nozzle is immersed in the mixture, wherein:
• subsequent to dispensing the wash liquid and prior to aspirating the portion of the mixture, shaking the array plate.