Labware Considerations

Introduction

Kaziya Lee, Applications Scientist, talks about the importance of using the correct labware for your assay.

Labware Considerations

Labware is a broad term that can encompasses plates, tips, reservoirs, and other items that can go directly onto the deck. As I’m sure you know, there is a huge variety of labware to choose from. You want to use the appropriate labware to successfully accomplish the steps of the method.

Just think about microtiter plates, there are so many shapes and sizes and colors out there from deep wells to low profile, from tube-racks to strip-tubes, from U-bottom to flat-bottom, and there’s even different materials to consider, like polypropylene and polystyrene – the list goes on.

All the options can be a little overwhelming. To simplify things, best practice is to start with the same labware that was used during the manual development of your assay. If you later encounter issues with your assay, or automation specific challenges, then modifications may be necessary. For example, you may want to introduce foil plate seals if on deck contamination is a concern. Or, you may want to switch to a microplate with an edge that works better with an automated gripper.

If you aren’t transferring a manual method, and are building from scratch, start with whatever labware that is used for other workflows on the robot. There are also other adjustments that can be made to increase efficiency that may require labware modifications. For example, a dispense step that was previously performed manually with a single channel pipette from a tube, could instead be done with an eight-channel dispenser arm from a reservoir.

The Importance of Using Manufacturers’ Tips

Speaking of pipetting, another important labware choose, is your tips. If your robot uses disposable tips, it is important to understand that not all tips are created equal. You will typically get the best performance from your robot by using manufacturer brand tips. Many manufacturers also produce a variety of specialized tip types for different applications, including filtered, low retention, and wide bore tips. Always follow manufacturers recommendations when deciding what tips to use for your application.

Take a look at this magnified image of two different pipette tips. On the left, is a robot manufacturer’s tip where the orifice is centered with a smooth, uniform appearance and made from a higher-grade material.

On the right you see a tip from a generic manufacturer. The orifice if off center and some flashing material still present, leftover from the injection molding process. It has a rougher appearance overall and is made from lower grade material.

It goes without saying, that quality is important, and more importantly, tips from different vendors can have significant differences in performance. If you do decide to use non-manufacturer brand tips, then you should consider conducting a tip qualification test to ensure they perform as expected.

Speaking of Tips…

I have a tip for you! A good way to check that the tips are properly seated and have an air-tight seal is to aspirate liquid, lift the head out of the reservoir, and then pause for about 30 seconds.

Observe and make sure that no liquid is leaking out of any of the tips. If leakage is observed, then additional troubleshooting is required.

To ensure a proper tip fit:

1. Service and calibrate dispensing heads as recommended by the manufacturer.
2. Tips should be seated straight and level across all channels.
3. There should be no tip leakage.

Conclusion

It is important to be aware of your labware options and the adjustments that can be made to better meet the needs of your workflow.