Proteomics has undergone the same existential choice, and self-examination, as other biological sciences with respect to automation. On the surface, automation helps laboratories cope with very high-throughput workflows.
Return on investment can be swift and convincing in an era where large testing laboratories seek to do more with less. Even medium-throughput labs can be convinced that the assay accuracy, consistency, and reduced human error (and its consequence—rework) that robotics bring make an even more compelling case for automation.
What about discovery-stage science labs operating at the lower echelons of throughput? Suparna Mundodi, Ph.D., global product manager at Rainin Instruments, offered a glimpse into what is in store for them at CHI’s “PepTalk” program on protein sciences. There, Dr. Mundodi presented the case for semi-automation, as exemplified by her company’s PureSpeed protein purification system.
PureSpeed uses a semi-automated pipetting protocol resident on the company’s E4 XLS electronic pipette, which processes up to 12 samples in parallel. But she said the stars of the show are Rainin’s PureSpeed tips, which purify microscale volumes of target protein, at very high concentration, in as little as 15 minutes. The pipette-fitting PureSpeed tips contain small volumes of standard chromatography resins concentrated in the tip region. Protein A, protein G, IMAC, and other formats are possible.
Rainin’s technologic competitors in ultra-small-scale protein purification are gravity chromatography and spin columns. Gravity entails very long sample prep times and is unsuitable for parallel processing. “You can’t do three or four samples simultaneously because you have to run between columns pouring buffer.”
The E4 XLS pipette draws and discharges a protein solution through the resin bed, cycling as much as needed to ensure adequate binding of protein to resin. After washing away impurities, the purified protein is eluted into a tiny volume suitable for such concentration-dependent analyses as surface plasmon resonance, electrophoresis gels, and ELISAs.
The official book on PureSpeed is it bridges the workflow gap between very low and medium-high throughput experiments. Actually, said Dr. Mundodi, the 12-channel system sits within the sweet spot for most early-stage research. “If you look at the protein purification market, 12 samples can be high throughput in many instances.” Her own market research, conducted before PureSpeed was developed, suggested that the average number of samples in PureSpeed’s target market was just under 10.
That tells only part of the story. The many benefits of automated liquid handling notwithstanding, it is often simpler and less costly to forgo automation, particularly in labs whose workflows are constantly changing. “Many of our customers, who may be doing expression screening on 40 to 50 clones, find the semi-automated system more straightforward, even faster, than fully automated systems.”
Since it is semi-automated (or semi-manual, depending on one’s perspective), PureSpeed requires no programming or extensive method development. With the inexorable drain of robotics and IT talent from many labs, semi-automation represents a welcome step forward.
“The best part is it’s a pipette, which makes people comfortable with using it,” said Dr. Mundodi.