This T-junction microfluidic technique was used by Dr Talha Gokmon to produce narrow
size distributions of polyHIPE microspheres. The polyHIPE maintains an open porosity
at the surface as the technique is in essence still a double emulsion method. PolyHIPE
monomer is introduced to a channel of flowing liquid which the ‘buds’ of the droplet
of monomer which is then cured and collected downstream. As long as all flow rates
and parameters remain unchanged each droplet buds of at the same size and changing
these parameters will change the resulting microsphere size.
The graph below illustrates the different size distributions formed from the two
techniques. Neither distribution is unwanted as it depends on the application. A
large range of microspheres sizes gives greater packing density while a narrow range
allows for predictability and controllability of the inter-particle gaps formed during
stacking (useful to ensure blood vessels have space to enter the formation
