Microfluidic Device for High-Throughput Production of Monodisperse Droplets

Abstract

In this study we present a novel microfluidic device for high throughput production of monodisperse droplets. The proposed 3D-emulsifier consists of multiple parallel droplet generators coupled to only two inlets (continuous and dispersed phase). The three-dimensional nature of our device allows for a maximal density of droplet generators per surface area. We produce oil droplets in water using a device containing a single and four droplet generators. The droplet size and throughput were experimentally determined. In the four nozzle chip, we observe an important effect of the flow rate on the size distribution between the different droplet generators.Importantly, the transition between the squeezing and a transition regime shows the highest monodispersed production rate. For the four nozzle chip, we show a four-fold increase of the production throughput, while maintaining a high monodispersity of the droplets. A theoretical scale-up of our device is performed, demonstrating a possible throughput of 8.2 l/h, opening the door for (industrial) applications requiring much larger flow rates than what is typically achievable with microfluidic devices. in the throughput for the four nozzle 3D-emulsifier. To ensure an appropriate flow distribution of the liquids, the final part of the distributor was design such that it has the highest pressure drop compared to the upstream part of the emulsifier. While the current 3-D emulsifier only had 4 nozzles, a theoretical scale-up under realistic conditions has been demonstrated. Expanding our design to a 1 cm² chip containing 2048 nozzles could give a throughput of 8.2 l/h. This is a significant increase compared to other nozzle array devices described in literature, paving the way for use of nozzle arrays in (industrial) processes requiring large throughput. ASSOCIATED CONTENT Supporting Information. Video S1, Droplet formation inside the droplet generator, Video S2, Droplet coming out of 3D-emulsifier, Video S3, Enlarged view of the droplet formation in the 4 nozzle 3D-emulsifier.

Rail configuration for lateral particle transport across intact co-flows: effect of wall and rail geometry on liquid and particle transport

“…Chips were made of two or three parts that were assembled and bonded inhouse with the use of butyl lactate that was introduced by the capillary force between the layers of the chip. 22 A profilometer (Filmetrics Profilm 3D) was used to determinate the depth of the rails. Liquid (ethanol) were introduced to the chip via glass capillaries (ID 450 mm, OD 670 mm, Polymicro, Achrom) that were glued to the chip inlets and outlets.…”

Rail induced lateral migration of particles across intact co-flowing liquids

“…The depth of the grooves was measured with a profilometer (Filmetrics Profilm 3D). The parts of the chip were assembled and bonded with the use of ethyl acetate that was introduced in the discrete amount between the layers of the chip 38 . Glass capillaries (inner diameter (ID) 450 µm, outer diameter (OD) 670 µm, Polymicro, Achrom) were glued to the chip inlets and outlets in order to introduce the liquids with the use of syringe pumps or pressurized pumps (Fluigent).…”

Rail induced lateral migration of particles across intact co-flowing liquids

“…The parts of the chip were assembled and bonded with the use of ethyl acetate that was introduced in the discrete amount between the layers of the chip. 37 Glass capillaries (ID 450 µm, OD 670 µm, Polymicro, Achrom) were glued to the chip inlets and outlets in order to introduce the liquids with the use of syringe pumps or pressurized pumps (Fluigent). In case of suspension of particles, a vortex mixer (VWR) was used to vibrate the Falcon tube containing particles suspension to prevent sedimentation of particles at the bottom of the Falcon tube.…”