Fast Prototyping of Off-Stoichiometry Thiol-Ene (Oste) by Aqueous Replica Molding

In this work, we developed a protocol to fabricate off-stoichiometry thiol-ene (OSTE) microstructures with a round cross-section - aqueous replica molding of OSTE, which is simpler and faster than traditional methods. Briefly, we generated hydrophilic regions on a hydrophobic polydimethylsiloxane (PDMS) substrate, then we soaked the PDMS substrate into a mixture of glycerol and water, and formed patterned liquid on it. After that, we dropped photocurable polymer OSTE on the patterned liquid, and cured it in seconds. Hemispheric microwells and semicylinder channels can be formed on OSTE. Crossing channels with different widths and heights can be manufactured in a one-step process. This protocol has also shown its ability to fabricate complex structures, such as serpentine or bent fluidic channels.