3. Several software, including AutoCAD, can be used to design
microstructures; however, files must be converted into
manufacturing-compatible formats, such as GDSII or CIF, to
make masks.
4. When designing microfluidic devices, there are general rules to
be respected, namely, the aspect ratio between microfluidic
height and width, in order to facilitate the manufacturing
process, insure the functionality of the device, and avoid collapsing of the microstructures. For instance, microchannels
having an aspect ratio between height and thickness of 1 or
0.5 are easy to manufacture. Diverse microstructures can be
conceived with different shapes and properties, which nonetheless must be tested and characterized. There are several
reviews describing the procedures to make these molds [40–
42].
5. Mask manufacturing is becoming increasingly popular and
manufacturing services are offered by several companies, such
as SELBA S.A. and TOPPAN PHOTOMASKS, INC. Resolution is the critical parameter to bear in mind when
manufacturing a mask, in other words, the minimum size of
the structures and the minimum space between structures. The
higher these parameters, the lower the resolution, defined as
Dots Per Inch (dpi). It is typically considered that structures
and interspaces above 6 μm necessitate lower resolution
( 50,800 dpi) and cheaper film or plastic masks; in contrast,
smaller
dimensions
necessitate
higher-resolution
(!64,000 dpi) and more expensive quartz masks.
6. The size of an individual mask is typically equal to 5 Â 5 in.
However, especially in the case of film or plastic masks, the size
can be larger, in order to contain an array of several masks,
either different variants of the same design or different designs.
7. To produce SU8 permanent epoxy negative photoresist layers
of different thicknesses, refer to the Microchem manufacturer’s
instructions, both with respect to viscosity and processing parameters, namely, spin-coating; soft bake; energy and exposure
time; post-exposure bake and development time.
8. The two inlet ports of the hexa-device can be connected either
to a single- or to a two-syringe infusion pump. In the first
instance, the 3 ends of a Y-connector are connected to three
strands of silicone tubing. While the tubing coming out of the
bifurcation is connected to the steel catheter couplers inserted
in the device, the third tubing is connected to a female luer,
which in turn is screwed to the single syringe. In the second
instance, two separate tubings are connected on the one side to
the steel catheter couplers and on the other side to the female
luers, which in turn are screwed to two syringes.
Microfluidic Microscopy of Mycobacteria
223
microstructures; however, files must be converted into
manufacturing-compatible formats, such as GDSII or CIF, to
make masks.
4. When designing microfluidic devices, there are general rules to
be respected, namely, the aspect ratio between microfluidic
height and width, in order to facilitate the manufacturing
process, insure the functionality of the device, and avoid collapsing of the microstructures. For instance, microchannels
having an aspect ratio between height and thickness of 1 or
0.5 are easy to manufacture. Diverse microstructures can be
conceived with different shapes and properties, which nonetheless must be tested and characterized. There are several
reviews describing the procedures to make these molds [40–
42].
5. Mask manufacturing is becoming increasingly popular and
manufacturing services are offered by several companies, such
as SELBA S.A. and TOPPAN PHOTOMASKS, INC. Resolution is the critical parameter to bear in mind when
manufacturing a mask, in other words, the minimum size of
the structures and the minimum space between structures. The
higher these parameters, the lower the resolution, defined as
Dots Per Inch (dpi). It is typically considered that structures
and interspaces above 6 μm necessitate lower resolution
( 50,800 dpi) and cheaper film or plastic masks; in contrast,
smaller
dimensions
necessitate
higher-resolution
(!64,000 dpi) and more expensive quartz masks.
6. The size of an individual mask is typically equal to 5 Â 5 in.
However, especially in the case of film or plastic masks, the size
can be larger, in order to contain an array of several masks,
either different variants of the same design or different designs.
7. To produce SU8 permanent epoxy negative photoresist layers
of different thicknesses, refer to the Microchem manufacturer’s
instructions, both with respect to viscosity and processing parameters, namely, spin-coating; soft bake; energy and exposure
time; post-exposure bake and development time.
8. The two inlet ports of the hexa-device can be connected either
to a single- or to a two-syringe infusion pump. In the first
instance, the 3 ends of a Y-connector are connected to three
strands of silicone tubing. While the tubing coming out of the
bifurcation is connected to the steel catheter couplers inserted
in the device, the third tubing is connected to a female luer,
which in turn is screwed to the single syringe. In the second
instance, two separate tubings are connected on the one side to
the steel catheter couplers and on the other side to the female
luers, which in turn are screwed to two syringes.
Microfluidic Microscopy of Mycobacteria
223