Further Improvements of PacBio Technology
Recently, we have reported on the Studies of the Broad Institute, showing that the PacBio RS system was able to outdo MiSeq sequencing regarding validation of SNP analysis. Now Pacific Biosciences have taken another important step to further improve their product.
Pacific Biosciences have now launched a new Sample Loading Device for the PacBio RS, called MagBead Station. As Michael Hunkapiller, Ph.D. President and Chief Executive Officer of Pacific Biosciences told in their press release, they expect that with the new device, customers will “be able to generate 10 kilobase-sized libraries using as little as one microgram of sample, a five to 10-fold improvement from where we were just a few months ago”. Also, because the new process is more robust, they expect that sequencing results will have higher overall consistency, allowing to run experiments also on challenging samples.
First experiences of early-access-customers seem to underline these expections:
As Patrick Hurban of Expression Analysis told InSequence, the new loading device allowed them to recover sequences also for “difficult” samples: “we’re much more confident on a sample-by-sample basis that we will be able to get good sequence”, he said. Also, they could confirm that the amount of library that needs to be loaded is now significantly lower. The new loading process also seems to favor longer DNA fragments over shorter ones, excluding short contaminating DNA fragments. This results in a greater percentage of long reads in a run. Also, the loading process now seems to work as efficiently for the large insert libraries as it does for the smaller insert libraries.
With the new loading device, about 50-60 % of the ZMWs are now active after loading. This is a great improvement compared to 30-45 % of active ZMWs before the upgrade.
When PacBio started on the market, I was impressed by the sophisticated new technology. However, the results of the first projects were rather disappointing. The new loading device now seems to greatly improve the sample loading step. However, the high error rates still remain a challenge, with about 15% for the time being. Pac Bio will need to solve those issues if they want to be successful on the market in the long run. However, it seems that by and by, PacBio is overcoming its “childhood diseases”.