µFLU Equipment
EQUIPMENT FOR THE PRODUCTION AND VALIDATION OF MICROFLUIDIC CHIPS
The following equipment is available to the users to manufacture and validate microfluidic chips.
MASK-LESS ALIGNER (HEIDELBERG INSTRUMENTS, ΜMLA)
By using photolithography, we can generate the mold (Masterwafer) on a silicon wafer coated with photoresist. The Mask-less Aligner is our instrument of choice, because it makes the use of chrome masks redundant and allows us to generate a high number of Masterwafers in a relatively short amount of time. The resolution of the instrument is in the range between 1µm to 200µm in z-direction, and the smallest feature in x-y is 1x1µm. Additionally to 2D microfluidic chips, it is possible to generate double-layer microfluidic wafers. They have the advantage of different heights incorporated in the same chip design.
INTERFERENCE PROFILOMETER (KLA, PROFILM3D)
After generating a Masterwafer (described under Mask-less Aligner (Heidelberg Instruments, µMLA)) it is crucial to measure the height of the generated structure. By using the interference profilometer we can precisely measure the height difference between silicon wafer and the exposed photoresist. The detection range is from 1µm up to 2-3mm.
HIGH PRECISION 3D PRINTER (MICROARCH S140)
The BMF microArch S140 is a precise digital light projection (DLP) printer with a layer thickness of 10µm. With the addition of the 3D printer, we can cover a bigger size range in preparing microfluidic devices. With a smallest resolution of 10µm, the printer allows for very fine feature sizes up to 14mm in height. Besides microfluidic devices, we are also using this instrument to prepare scaffolds or molds for different applications. Currently we have a biocompatible and a hard material resin available in the facility. On demand from the user, different resins can be purchased from the company by the µFlu CF. The printer also allows the usage of custom-made resins.
UPRIGHT MICROSCOPE (AXIOLAB 5, ZEISS)
We use the AxioLab5 upright microscope to control the quality of our fabricated devices.
MICROFLUIDICS EQUIPMENT
The following equipment can be used by the user to conduct the experiments in the Microfluidics Core Facility
FULLY-FEATURED MICROFLUIDIC STATION
The microfluidic station consists of multiple instruments:
- High-Speed Camera (FastCam MiniUx50, Photron)
- Light microscope (AxioVert A1, Zeiss)
- Pressure-based Flow Controller (Elveflow)
- Syringe Pumps (ISPLab01,InfuseTek)
All instruments can be used after an introduction to the system. The microscope is also equipped with a LED and 3 different filter cubes (405nm, 488nm and 550nm) for observing fluorescently-labelled specimen. However, the high-speed camera is monochromatic, meaning that no fluorescent high-speed videos can be recorded. The frame rate of the high-speed camera is 2000fps at the lowest resolution of 1200x1048, by tuning the resolution, higher frames/second can be recorded. Given the final application either the syringe pumps or the pressure-based flow controller is used. Volumes from 0.5µl up to 150ml can be used with those syringe pumps and from flow rates starting at 0.002µl/min up to 165.8ml/min. In contrast, the Elveflow system works with pressures from 0 to 2bar, expanding the application range with the microfluidic set up in the facility. We also own a pressure sensor and a flow sensor which allow us to read out the proper pressure inside the channels and automatically calculates the flow rate from the applied pressure, respectively.
MICROPULLER (WPI, PUL-1000) AND MICROFORGE (WPI, MF200)
Besides PDMS-based microfluidic chips there are also glass capillary-nested devices. Mostly, such devices are sued to prepare water-in-oil, oil-in-water or water-in-oil-in-water droplets. To assemble such a device, it is necessary to cut and forge the opening of glass capillaries exactly to the size of the final droplet dimensions. To do so, we have a micropuller and a microforge, which can be used by the users after an introduction.