Miroculus unveiled at AGBT their Miro Canvas system. This consists of a small footprint benchtop control unit and consumable cartridges. The system is based on electrowetting microfluidic technology. Electrowetting chips consist of a grid of squares which can be individually addressed. By changing the polarity of the square, the surface can be made either hydrophilic or hydrophobic. Sample or reagent aliquots can then be made to migrate across the surface by appropriate shifts in the polarity of adjacent squares, and such movements can include droplet splitting and merging. Other elements have been placed on such devices, such as electromagnets for bead operations or thermal elements to enable thermocycling.
Electrowetting has had a rocky history in sample prep. Advanced Liquid Logic (ALL) developed such technology and first licensed it to NUGEN for its Mondrian system, which was later discontinued when Illumina purchased ALL and launched NeoPrep, which gathered a poor reputation on reliability and was discontinued. Oxford Nanopore has worked many years on VolTRAX, which also uses electrowetting. VolTRAX had a very long gestation period and by my completely unscientific analysis of Twitter never seems to get much traction.
Miroculus claims their system has two key advantages over prior ones. One is that the chips do not use oil to encapsulate the droplets; a major complaint during the early VolTRAX beta period was the leaking of oil from the consumable cartridges. No oil also means that the device can potentially apply mechanically vigorous methods without fear of generating emulsions and makes it compatible with ethanol and other chemicals that interact with oil. The other is that the disposable cartridge has zero electronics in it; the electronics are all in the controller. They claim this will enable lower failure rates of the cartridges, as well as a higher degree of recyclability.
Another important feature of the devices is the ability to sense droplets, so that the system can detect droplets that haven't gone where they have been directed. The initial offering will enable prepping a single sample and is aimed at owners of benchtop sequencers. Twist and Miroculus have announced an agreement to port Twist's library prep and enrichment technologies onto the platform. Miroculus' website has posters for a variety of protocols, from PCR-free genomic library construction to cell free DNA purification and even non-molecular biology methods such as combinatorial chemical synthesis.
An important component of the platform is the MiroPalette software, an appropriately colorful visual programming tool for designing programs for the system. In my mind, this turns Miro Canvas into a microfluidic equivalent of an old electronics breadboard, allowing scientists with minimal experience to experiment with constructing microfluidic workflows. Protocol design is high level: the user specifies high level workflows rather than something more resembling chess notation to direct each move. An interesting component of MiroPalette is that after a protocol is designed, the system generates 1000 simulated specific designs to identify the best one. This optimization includes considerations such as avoiding overuse of the same squares, which can lead to fouling, and undesirable crossing of reagent paths.
The initial kit will support single samples and go for around $30 a cartridge; the controller is expected to price at $25K. This will support protocols with 12 reagents and three large volume wash reagents. Beta testing is expected to commence in July with shipping by the end of this year.
It's an intriguing entry into the low throughput sample prep market, potentially removing user-to-user and experiment-to-experiment variability as well as the option of writing your own routines. Oxford Nanopore has promised opening up VolTRAX for some time, but has been slow to deliver that. Whether their promises of reliability hold true is something only customers and experience can answer. Finally, don't expect Miroculus to be the last company to market electrowetting-based methods; yet another startup had a poster at AGBT. But are we running out of appropriate modern artists for branding these devices? Time will tell.