QUESTION 1

Where does your Purigen Biosystems story start?

I became acquainted with the needs in sample prep while I was working at LLNL (Lawrence Livermore National Laboratory) on a project to use a series of microfluidic techniques to purify viruses from complex samples. We needed a way to separate out free nucleic acid and, having done my graduate work in Prof. Juan Santiago’s lab at Stanford, I knew ITP (isotachophoresis) would be an ideal solution for this. As it turns out, just a few months earlier, Prof. Santiago and his group had started working on this application of the ITP technology. Working together, we implemented a unique implementation of ITP for flow-through separations. I left LLNL soon after to join a startup, QuantaLife, to help develop their droplet digital PCR system. After the company was acquired by Bio-Rad, Juan and I started discussing how we could commercialize the impressive solutions he had developed for purification, separation, and quantitation.

QUESTION 2

How did you arrive at the decision to focus on nucleic acid purification?

Prof. Santiago had already demonstrated that ITP was very efficient at concentrating and purifying DNA and RNA from samples along with several other capabilities. We interviewed > 100 people to get a sense of the biggest needs and it was clear that people were struggling with nucleic acid purification, especially for precious samples.

QUESTION 3

In the beginning, what did you think your biggest challenge would be?

Scaling up the process to use real-world input volumes. Initial development in Prof. Santiago’s lab had started at < 1 µL of input. We knew we needed the input volume to be closer to 100 to 200 µL to enable us to lyse cells, tissue, and other inputs.

QUESTION 4

Looking back, what was your biggest challenge?

Scaling the process probably has been the biggest challenge. By pushing input volumes to 200 µL to enable effective lysis, while also parallelizing the process to purify 8 samples at a time, we moved out of the normal “microfluidic” regimes. This brought along additional considerations we could normally ignore at smaller scales.

QUESTION 5

From a technical perspective, what was your approach to developing Purigen’s first product?

As with most technologies in life science tools, the product is a system. The instrument, chemistries, and chip must all work together in order to make the product robust. Several times we found that an issue that seemed specific to one component was actually due to an interaction between all three. By treating them as a system, we were able to develop solutions to make the product much more robust.

QUESTION 6

Did you learn anything new about isotachophoresis in the process of building a product that leverages the technique for nucleic acid purification?

ITP is often counterintuitive, so even with an extensive background in electrophoresis, it took me some time to get an intuition for how it works. Thankfully, we have experts on our team that have taught me, and the rest of our technical staff. One very interesting thing we have learned a lot about is how subtle differences between nucleic acid, such as length or concentration, impact its migration through a microfluidic channel in ITP.

QUESTION 7

As the head of R&D, can you provide a sneak peek into what may be coming down the road for Purigen Biosystems or the Ionic^® Purification System?

Next will be RNA from FFPE, then RNA from cells followed by DNA and RNA from fresh/frozen tissue. The last of those developments should be completed by early 2021. A kit for purifying high molecular weight DNA will likely follow. We’ll also continue our research efforts on purifying nucleic acid from plasma and blood. Our plan is to combine our internal efforts with customer collaborations to expand our portfolio of kits and cover a broader range of sample types.

QUESTION 8

We are all looking for positive news these days. Can you share a positive impact the current pandemic has had on Purigen Biosystems?

One positive I have seen from the pandemic is the way the Purigen team has worked together so well. Our safety plan limits the number of people in the building at one time and splits the work across shifts. This has required the team to be even better about communicating to help coordinate experiments, troubleshoot issues, and safely hand-off materials. Tools like Slack have helped keep communication very fluid among the team and everyone has worked hard to ensure that whoever is in the building can get help answering questions or talking through any troubleshooting they may need to do.

QUESTION 9

What advice would you give any scientist with a cool technology interested in starting a new company in the biotech space?

It’s easy to think “I’ll just raise a bunch of money and get this technology built and to market.” My advice, and I’ve seen this with several other companies, is to really focus on answering the hard questions first with a small team and some seed funding. Then you know what you’re up against and what type of expertise you will need as you grow.

QUESTION 10

As Purigen Biosystems grows, is there anything about the company that you do not want to see change?

I really like how well the teams work together. As I mentioned before, the fact that the product is a system means that all of the teams need to interact, understand how the pieces work together, and contribute solutions based on their expertise. This mindset is also important at the business level as well, as R&D, Sales, Marketing, and Operations all depend on one another and have to work together on solutions.