Pioreactor v1.5 is here!
At Pioreactor, we believe that you should be getting the best bioreactor we can provide. While working on a larger revision of the Pioreactor, we recognized a hardware upgrade that can be back-ported to the current Pioreactor. We're calling this hardware upgrade the Pioreactor v1.5 (as a nod that it's between a 1.0 version and the next 2.0 version), available for both the Pioreactor 20ml and Pioreactor 40ml. Both the Pioreactor 20ml v1.5 and Pioreactor 40ml v1.5 are available today! And like always: upgrade kits to v1.5 are available, too!
What's new in v1.5
The biggest change is how we are collecting optical density signals. Previously, we used a 5mm photodiode connected to a (relatively) long cable, connected to the HAT. The HAT had all the amplification and conversion hardware. We recognized three issues with this approach:
- The long cable was an antenna for electro-magnetic interference. You may have saw additional noise in your OD readings if you brought a laptop or light source close to the photodiode cables, or even if you touched the cables during operation.
- The conversion from an analog signal to a digital signal was through a low-resolution ADC (the RP2040, if you are curious). This ADC has 8-bits of conversion, meaning we could convert an analog signal into one of only 255 buckets. We sample many times, which improves the "bucket" space size, but it's still limiting.
- Finally, the 5mm PDs weren't secured into the side of the Pioreactor reliably. This could cause shifts during operation or moving the device. Furthermore, two Pioreactors might have very different positions of the photodiodes, leading to differences in their raw signals.
Our solution was simple: construct a new top-vial-holder with a secure position for a dedicated photodiode circuit board. We call this circuit board the Eye-Spy board.
The Eye-Spy circuit board
In the Pioreactor v1.5, both the REF and 90 signal photodiode are replaced by the new Eye-Spy boards. Each Eye-Spy board is a significant improvement versus the old photodiode-bulb design. Its onboard ADC has 16-bits of resolution (that's 65,535 buckets now), twice as much amplification, and highly resistant to external noise. It is secured to the Pioreactor using four screws instead of a friction-fit cap, meaning it won't ever shift. All this culminates in much lower noise in your OD measurements! Up to 3x lower noise and less sensitivity to outside interference.
Finally, it's fully STEMMA QT compatible! This fits nicely into the rest of the STEMMA QT ecosystem and you can chain the Eye-Spy together with other STEMMA QT boards.
What happens to the old photodiode + cable solution? It's no longer used for OD measurements, but we suggest holding onto this old hardware. We'll later have some blog posts on how to re-use them for additional sensors in your setup.
Other design changes in the v1.5
The top-vial-holder has some other improvements as well. There's a newly redesigned pocket for the Adafruit Spectrometer (and other boards of the same shape), and a new pocket for an LED-on-a-PCB.
Finally, the Pioreactor 20ml is getting the new poka-yoke design to fit the Vial Cap S (which is included in the Pioreactor 20ml v1.1 → v1.5 upgrade kit).
An update on pricing
Since late 2022, we've held onto the $249 USD price of a Pioreactor 20ml. With the new optics hardware and rising costs for all our components, we felt it was time to update our pricing. Each model of Pioreactor is increasing by $50 USD each. So you can still get a Pioreactor 20ml under $300 USD - a ridiculously inexpensive price for a bioreactor.
The v1.5 update kits are more affordably priced at $39.50 USD because really want all existing users to upgrade to v1.5! The v1.5 will also be the base for which we release an eventual v2.0 upgrade kit.
Outstanding orders and quotes
If you have made an existing order with us, or have an outstanding quote, you'll be automatically upgraded to the v1.5, free of charge! Shipping starts today!
What's next
Along with the Pioreactor v1.5, we have a significant software update you'll want to check out. See an upcoming blog article for more information.
We continue to work on a v2.0, but it's much further out. It's an entire redesign of the system using what we have learned about designing and manufacturing small bioreactors from the past three years.
As always, thank you for being a part of this journey!