Advanced Pipetting Technology Helps Optimise Protein Purification Processes

Rainin Instrument, a METTLER TOLEDO subsidiary, has published a white paper describing the optimisation of protein/antibody purification. The paper, entitled ‘Optimizing Protein Purification Conditions’, highlights the use of Rainin PureSpeed protein tips. Using Rainin’s E4 XLS electronic pipette, PureSpeed tips allow for bidirectional sample flow over the purification resin bed, maximsing target protein capture by allowing the binding reaction to reach equilibrium. Potential concentration steps, which can actually degrade protein quality, are eliminated, saving time and costly rework.

To demonstrate the process, a 6-His-tagged protein and s 20 µL Ni-IMAC PureSpeed tips were used with a Rainin E4 XLS pipette. Back-and-forth capture flow was used to ensure complete resin exposure during all steps. Concentrations of imidazole in the wash buffer and final elution were varied to help illustrate purification optimsation, targeting both quantity and purity of captured protein. The experiments illustrate that PureSpeed wash and elution chemistries, which are carried out at reduced volumes, generalise to larger scale preparative systems, making PureSpeed a cost-effective optimisation tool.

The paper also reviews aspects such as protein size that can affect the capture equilibrium as well as ways to help enhance protein capture by adjusting pH and flow rate or increasing cycle numbers. Rainin’s ColorTrak Guide also proved useful at helping non-expert operators load and purify a specific protein or antibody.

For more on how Rainin and proprietary PureSpeed technology can help optimise protein purification processes for time and cost savings, download the complete white paper at bit.ly/optimisingproteinpurification.

Rainin Instrument, LLC, +1 510 564 1736, terry.peckham@rainin.com, www.mt.com.