The Research on Multi-material 3D Vascularized Network Integrated Printing Technology.

Shuai Yang,Hao Tang,Jiquan Yang,Chunmei Feng,Jianping Shi

doi:10.3390/mi11030237

Abstract

Three-dimensional bioprinting has emerged as one of the manufacturing approaches that could potentially fabricate vascularized channels, which is helpful to culture tissues in vitro. In this paper, we report a novel approach to fabricate 3D perfusable channels by using the combination of extrusion and inkjet techniques in an integrated manufacture process. To achieve this, firstly we investigate the theoretical model to analyze influencing factors of structural dimensions of the printed parts like the printing speed, pressure, dispensing time, and voltage. In the experiment, photocurable hydrogel was printed to form a self-supporting structure with internal channel grooves. When the desired height of hydrogel was reached, the dual print-head was switched to the piezoelectric nozzle immediately, and the sacrificial material was printed by the changed nozzle on the printed hydrogel layer. Then, the extrusion nozzle was switched to print the next hydrogel layer. Once the printing of the internal construct was finished, hydrogel was extruded to wrap the entire structure, and the construct was immersed in a CaCl2 solution to crosslink. After that, the channel was formed by removing the sacrificial material. This approach can potentially provide a strategy for fabricating 3D vascularized channels and advance the development of culturing thick tissues in vitro.

Highlights

A million patients need transplants because of organ failure, but the number of transplants available is still far from enough
Three-dimensional (3D) printing can produce complex multi-material structures with controllable shape structures and controllable material components, which has become the first choice of tissue engineering [1,2,3]
The development of a biomimetic 3D vascular system would be of vital importance [6,7]

Summary

Introduction

A million patients need transplants because of organ failure, but the number of transplants available is still far from enough. Extrusion-based bioprinting, the most common technique, consists of dispensing a continuous filament through a nozzle using a piston, a screw, or pneumatic system to construct a 3D structure layer-by-layer This technique provides an accurate ink deposition (resolution > 100 μm) and a homogenous cell distribution with faster printing speed. Schöneberg et al used drop-based bioprinting to generate blood vessel models in vitro mimicking a native vascular channel [16] Their method was to deposit droplets of three different hydrogels containing three different cell types in a definite spatial layout to simulate the different layers of a native vascular channel. We propose a novel bioprinting approach on how to print sacrificial ink into the hydrogel matrix to fabricate perfusable channels, based on the combination of extrusion and inkjet techniques. We report an important advance as our approach can create user-defined (shape, size, and location) and perfusable channels embedded within a hydrogel matrix in an integrated manufacture process

Bioprinting System

Materials Preparation

Parameters Optimization

Paarameterrss Optiimmiizzaattiioon

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