New microfluidic chip for the production of spherical gelled capsule for cell encapsulation

P. Dalle, S. Morales, J. Berthier, P-Y. Benhamou, A. Bellemin Comte, F. Boizot, G. Costa, F. Rivera
CEA/LETI, FR

Keywords: microfluidic, alginate, pancreatic islet, encapsulation, automation, phase transfer

Summary:

Implantation of Langerhans islet in alginate shell is an alternative for the treatment of diabetes type 1. Finding an adapted process for cell encapsulation is a challenge. The process must product spherical and monodisperse capsules in a limited time with a good reproducibility. Up to now conventional systems are mainly manual which induces batch disparities and do not provide repeatable clinical results. In this paper, we report a novel microfluidic device coupling a production of alginate droplets in an oil flow and a phase transfer module, that automatically transfers the capsules in an aqueous phase. This module allows a 100% extraction of alginate capsule from the oil phase to a calcium gelling solution. Gelled spherical capsules are directly retrieved in an aqueous phase. The entire process is done at physiological pH without any surfactant.