Injection Moulded Microfluidic Device for Bio-tech Company Droplet Genomics

Droplet Genomics is a bio-tech company disrupting new ground in high performance analysis technologies. This company enables scientists get into and explore the vast field of biology world. Droplet Genomics produces tools for the scientists that are easy and simple to use for their explorations and precise findings.

The core focus of this company is a droplet microfluidics technology which provides unmatched capabilities for researching the cosmos of biology. This technology empowers scientists to investigate biological samples at the resolutions of a single cell. In combination of life sciences, machine learning and engineering this company provides a whole platform for a high-throughput exploration.

What are the microfluidic chips?

Microfluidic chips are the components that are used in high-throughput biological research. They are the core in fluidic droplets handling operations: generating, splitting, merging, mixing, storing, injecting. Such platform contains micro-channels, obstacles and reservoirs to achieve these operations. It requires a great deal of knowledge to design such structures and channels to achieve the desired goal of the chip. However, manufacturing of such systems requires no less of knowledge too.

High volume chips’ production

When microfluidic channels are tested and confirmed for the desired research objective, higher volume of the chips may be demanded and this is where Micromolds company with micro injection moulding could step in and cooperate with Droplet Genomics.

Not only does injection moulding come handy because of its high productivity but also because it enables the possibility to make non-micro structures – like the reservoirs, wells, inlet and outlet gates together with micro geometries in one single moldable piece. However, this comes at a certain cost which is challenging for any injection molding professional.

Tooling challenges

When things get really small, regular machining might not be an option even though theoretical machine and tool precision would let do so. For such micro tools we had to use tool inserts that are located inside the mold base. Since the high plastic injection pressures forces are exerted inside the mold cavity and core, we had to experiment a lot with different machining options of those inserts – from laser ablation to multiphoton polymerization.

Manufacturing the insert is just one side of a coin, the most challenging task was to locate the insert inside the mold base so that alignment of the core and cavity would be perfect and the clamping forces would not brake the inserts.

Injection Challenges

Extremely flat surface of the chip was needed to make micro geometries possible. This meant that any sink marks caused by the uneven wall thickness had to be solved. However, we could not make walls thinner than the smallest ejectors we had since this would have caused us demolding problems. In fact, it did. At the first trials the ejectors were too weak and started to bend.

As a way out we had to play with injection parameters to reduce the sink marks to the minimum so the wall thickness could remain unchanged and thus thicker ejectors could be used.

The results

We are happy that we were given an opportunity to grow together with our client in solving really challenging tasks. Such projects force us to enter to the whole new market of microfluidic chips molding. There is no doubt our companies will continue on cooperating in the future to enable high-efficiency biological exploration through droplet microfluidic technology.