A system and method are provided for fabricating 3D structures from biomaterial. The system includes a printer assembly having a dual-arm assembly including an upper arm, and a lower arm connected by an elbow joint to the upper arm. A disposable barrier encloses a printing surface from an external environment and from components of the printer assembly. The upper arm and lower arm are inserted into an inlet of the barrier, so as to be isolated from the print surface. The lower arm is provided with an extruding system, and the extruding system includes an actuator-driven syringe configured to deposit biomaterial on the print surface. The biomaterial is deposited on the print surface to carry out 3D fabrication in an aseptic environment.