The Integrations of Biomaterials and Rapid Prototyping Techniques for Intelligent Manufacturing of Complex Organs - Advances in Biomaterials Science and Biomedical Applications - page 449

4.2. The double syringe cell assembling technique

Different from the above single syringe cell assembling technique, a double syringe cell assem‐
bling technique was developed in Tsinghua Unversity with a updated software and hard‐
ware. Gradient and cylindrical architectures consist of two different cell-laden hydrogels have
been fabricated at a temperature range of 8 - 10℃ [59,60]. Two cell lines encapsulated in the
similar gelatin-based hydrogels were put into different regions or compartment in a construct
(Figure 5). The embedded branched networks enable culture medium to flow through the en‐
tire construct with unparalleled geometric complexity. However, there is a fatal shortcoming
of this system to be used in complex organ manufacturing. The mechanical weak properties of
the gelatin-based hydrogel made it impossible to connect the branched construct to an in vivo
vascular system to endure anti-suture anastomosis and blood pressure even after a long-term
in vitro culture period.

Figure 5. Cell assembling based on a two syringe RP technique developed in Tsinghua University, prof. XH Wang'
group. Two different cell types in the gelatin-based hydrogels can be assembled simultaneously into a construct
[59-60].

4.3. The combination of cell assembly and cryopreservation techniques

With the advantages of the gelatin-based hydrogel, cryoprotectants (e.g. dimethyl sulfoxide
(DMSO), glycerol, and dextran-40) can be incorporated into the cell/hydrogel system and the