In the “Pipetting” menu, you can set several options according to the needs of your application. These pipetting parameters are organized in four sections: Configuration, Advanced, Automation and Guidelines.
Under the “Advanced/Handling liquid viscosity” section in the “Pipetting” menu, you can set different speeds: the aspiration speed, the dispensing speed and the pipette moving speed.
For water based reagents, the “normal” settings are advised, while depending on the physical properties of the reagents involved, you can choose between other values.
Typically, for highly viscous liquids, the speed should be set to “slow”, both for aspirating and dispensing, although you can change these parameters independently. For low viscosity liquids, you might want to aspirate and dispense faster than normal. In addition, for some applications and with some reagents, it might be important to move the pipette slowly from the source to the destination. Therefore, you have the possibility to reduce the speed of the pipette movement. The slow aspiration and dispense mode will set the Andrew Alliance pipette on its lowest speed during the protocol execution with an Andrew+ unit or a Pipette+ stand.
Besides the speeds you can also choose whether or not you want to apply an air cushion by (un)checking the “Air top cushion (High viscosity aspiration)” or the “Air bottom cushion (Low viscosity aspiration)” checkbox. This option requires some experience on your side, since enabling it mainly depends on the reagents that are involved during this pipetting action. The top air cushion is for highly viscous liquids and the pipette will aspirate air before the liquid so that after the dispensing the leftover liquid in the tip will be pushed out, while the bottom air cushion reduces undesired dripping of lowly viscous liquids.