The APCN double emulsion microcapsules were prepared using a Lego®-inspired glass capillary microfluidic device developed by the group of Vladisavljević, which offers a greatly simplified approach to double emulsion microfluidics compared to manually assembled glass capillary devices and allows the use of hydrophobic monomers. The device consists of two plastic blocks that can be easily joined together and separated using a Lego-inspired stud-and-hole coupling system that aligns the incorporated glass capillaries. The plastic blocks host two round glass capillaries inside a coaxially aligned round outer capillary. Figure schematically shows the configuration of the capillaries and the overall experimental set-up for the preparation of double emulsion microcapsules. One syringe pump delivered, in two separate channels, the water-based inner phase and the middle oil phase, which contained toluene as water-immiscible solvent, as well as the hydrophobic monomer 2-(trimethylsilyloxy)ethyl acrylate (TMS-HEA), the hydrophobic macromolecular crosslinker ,dimethacrylate-terminated PDMS (MA-PDMS-MA) and a photoinitiator for free radical polymerization, in a 50:50 wt% composition of PHEA and PDMS. A second syringe pump delivered the 2 wt% of PVA -based outer phase. W/O/W double emulsions were formed in the microcapillary device and collected in a vial, which was irradiated with UV-light to initiate the polymerization and to form hydrophobic polymer conetworks in the oil phase. They were then converted into PHEA-l-PDMS amphiphilic polymer conetworks by cleaving the TMS groups in an isopropanol-water mixture.