How to Properly Pipet: Step-By-Step Pipetting Techniques

As with all highly sensitive immunoassay platforms, proper pipetting techniques are important for generating high-quality data. Uncover how to properly pipet with general considerations related to micropipetting when running Single Molecule Counting (SMC^®) assays including step-by-step pipetting techniques for forward pipetting and reverse pipetting.

• General Pipetting Tips
• Forward Pipetting
• Reverse Pipetting

General Pipetting Tips

• When pipetting, it is important to use the correct pipettes and tips based on the volume to be transferred.
• Aspiration should be performed with the pipet at a vertical orientation ensuring that the liquid is evenly distributed across the channels, whereas dispensing is most accurate at a 45-degree angle and by touching the tip against the vessel wall.
• If pipetting small volumes, pre-wetting is important to minimize the effects of sample evaporation.

Forward Pipetting

Forward pipetting is suitable for transferring aqueous solutions. It can be used for performing serial dilutions, reconstituting standard material, and adding samples to the filter plates during the SMC^® immunoassay workflow.

Step-By-Step Forward Pipetting Technique

• Begin by turning the pipette volume dial to the correct setting and loading the pipet tip.
• Hold the plunger at the first stop and vertically lower the tip to a suitable depth below the liquid surface.
• Next, pre-wet the tip 3 times and slowly release the plunger to aspirate the sample and bring the pipette over to transfer the liquid into the receiving vessel.
• To dispense the contents, angle the pipet tip at 45 degrees and dispense the sample by pressing the plunger to the first stop while touch tipping against the vessel well. This will help avoid generating bubbles.
• Do not blow out from the pipette when dispensing as this will also generate bubbles. Doing this maximizes precision among replicate wells.

Reverse Pipetting

Reverse pipetting, or repetitive pipetting, is useful for quickly and precisely dispensing small and equal volumes of liquid from the same source to multiple wells using the same set of tips. This method can be used while distributing coated microparticles and dispensing detection antibody solution.

Step-By-Step Reverse Pipetting Technique

• Begin by depressing the plunger past stop one and aspirate the liquid.
• To dispense the liquid, touch the tip against the vessel wall and push the plunger only to the first stop to dispense the intended volume.
• Do not go past the first stop as the residual liquid in the tip is the difference between the originally aspirated volume and the desired volume required in the well.
• From there, the same sequence can be used to aspirate and deliver liquid to additional wells using the same tip.

Learn more tips and tricks about how to handle Aurora reading plates in our SMCxPRO^® Best Practices article.

For Research Use Only. Not For Use In Diagnostic Procedures.