Multimodal 3D Printing of Phantoms to Simulate Biological Tissue

Spin-coating, polyjet printing and fused deposition modeling are integrated to produce multilayered heterogenous phantoms that simulate structural and functional properties of biologic tissue. Lack of traceable phantom standards that simulate structural and functional heterogeneity of biologic tissue has become the bottleneck for development and validation of biomedical optical devices. This video shows layer by layer fabrication of heterogeneous tissue simulating phantoms by integrating multiple additive manufacturing processes such as spin coating, PolyJet printing and FDM in a production line of 3D printing.

Technical capability of such a production line is exemplified by the automatic printing of skin-simulating phantoms that comprise epidermis, dermis, subcutaneous tissue and an embedded tumor. Material preparation for spin coating printing. Add titanium dioxide powder into SLA photopolymer Resin, stir for 30 minutes on a magnetic stir.

Seal with tin foil and sonicate. Vacuum for 10 minutes. Load it into the storage syringe Material preparation for polyjet printing.

Add material, sonicate, add Chinese Red Dye, load them into the cartridges, put cartridges into the printer. Material preparation for FDM printing. Heat low-density gel wax on a magnetic stir.

Add titanium dioxide powder, add graphite powder into the second beaker. Vacuum load them into the extruder of the hybrid three nozzle module. Design of digital optical phantom of skin Setting up parameters for spin-coating.

Set up the parameters of rotating speed and duration in the control software. setup the amount of spin-coating material and the time of light-curing. Preparation of source file for polyjet printing, Import the blood vessel image into the software, set the print position and set the inkjet parameters generate the PRN file needed for printing after the setup is complete preparation of G-code for FDM printing, import the tumor model into the Cura software add the all in one nozzle slicing script into the Cura software and slice the model to generate the G-code required for printing Documents import of the printing control software.

Click the File menu item in the menu bar. Load the UV printing PRN files. import the G-code.

Click the Start printing button. The mechanical hand moves the substrate on the loading station to the center center of the spin-coater sample stage. The glue dispenser controls a syringed drip the material to the center of the substrate.

The spin-coater starts to work. Drop the UV lamp and turn it on and the skin epidermis will be printed. Move the substrate to the 3D mobile platform.

Move the substrate to the initial position of the UV printing, push the inkjet printer to the working position. The inkjet printer prints the picture. The UV lamp is pushed by the cylinder and moved down to the position above the substrate, turn on the UV lamp.

Repeat for the next layer of printing until the multilayer printing is complete. The mixing nozzle is moved to the working position by the push of the cylinder print according to the instructions of the G-code. The print is completed until the subcutaneous tissue portion of the tumor portion is printed.

Move the substrate back to the loading station cast the subcutaneous layer phantom with the help of a mold Representative results. Result of automated printing production line. By integrating the 3D printing methods, the system could create a tumor like phantom by following the steps in the protocol.

Taking the simplified multilayer skin model is an example. The epidermis layer, dermis layer and subcutaneous tissue layer with different thicknesses and different optical properties are fabricated by the spin coating method, polyjet printing method and FDM printing method. Through the model the possibility of combining spin coating, polyjet printing and FDM printing to produce optical phantoms was verified it is proved that the system has the potential to produce tissue optical phantom with optical simulation characteristics and structural simulation characteristics.