Growth of microtissues in microencapsules formed using microextrusion and vibration

Microencapsulation technology had been widely used in biological study, drug delivery, cosmetic and also food industry. Previous methods developed for microencapsulation is complex in terms of their design and handling. A simple micro extruder device with vibration mode was developed to microencapsulate HaCaT cells in calcium alginate capsules at 10 to 60 Hz. The microencapsulated cells proliferated and formed into microtissues. Alginate lyase was applied to remove the microtissues from the encapsulation and for studying the cell adhesion in the microtissues. DAPI and live/dead cell stainings were applied to study the organisation and viability of cells, respectively. Via the nuclei staining, it was found that the distance between cells reduced as the incubation period increased. After 15 days of culture, the cells were viable as indicated by the fluorescence green expression of Calcein-AM. Replating experiment indicated that the cells from the microtissues were able to migrate and has the tendency to form monolayer of cells on the culture flask.