WO2017143356A1

WO2017143356A1 - High temperature module for a 3d biological printer deposition system

Info

Publication number: WO2017143356A1
Application number: PCT/US2017/021270
Authority: WO
Inventors: Wei Sun; Qudus Hamid
Original assignee: Sunp Biotech, Llc
Priority date: 2016-01-25
Filing date: 2017-03-08
Publication date: 2017-08-24

Abstract

This present invention provides a high temperature module for a 3D biologies printer's deposition system. This module is designed to be adaptive and integrative to current biological printers while providing the ability to maintain a "hot" environment within the fabrication head. A "hot" environment is defined as changing and maintain the temperature within the printer's fabrication system of at least one degrees Celsius (1 degree C) above ambient temperature.

Description

HIGH TEMPERATURE MODULE FOR A 3D BIOLOGICAL PRINTER

DEPOSITION SYSTEM

BACKGROUND

Researchers in the field of tissue engineering and regenerative medicine have begun to realize that complex, multicellular systems are needed for improved testing and growing large organs and tissues (have been difficult to develop due to lack of a blood supply to transport oxygen and nutrients). Conceptually, 3D printing could print complex structures required to transport oxygen and nutrients and could print cells, extracellular matrix, and growth factors precisely to create samples that better mimic in vivo tissue.

The key of successfully building a functional tissue construct, is having the right tool. In order to assemble cells into a functional array, the material delivery system must sustain cell life and have full control of the fluid/bio-suspension being printed. Most importantly, a printer's deposition system must have the capabilities to handle and/or utilize an expansive library of biologically compatible materials. This library will increase the printer's abilities to fabricate more complex physiologically relevant tissue constructs. Due to the nature of many biological materials, cells, and the design of many biological printers; there is a need for a temperature module. One that can adapt to current fabrication system. This temperature module will be primarily responsible for heating of the fabrication head. Heat can be used to maintain a cell friendly temperature or even heat polymers such that its viscosity changes, making it printable.

This article presents a high temperature module for a 3D biologies printer's deposition system. This module is designed to be adaptive and integrative to current biological printer while providing the abilities to maintain a "hot" environment within the fabrication head. A "hot" environment is defined as changing and maintain the temperature within the printer's fabrication system of at least one degrees Celsius (1°C) above ambient temperature.

BRIEF DESCRIPTION OF THE DRAWINGS

For a fuller understanding of the nature and desired objects of the present invention, reference is made to the following detailed description taken in conjunction with the accompanying drawing figures wherein like reference characters denote corresponding parts throughout the several views and wherein:

Figure 1 depicts a round heating element with heating wires enclosed within the walls;

Figure 2 depicts a rectangular heating element with a ceramic heating wire

embedded at the corner;

Figure 3 depicts the configuration of the PID controller with the heating element; Figure 4 depicts the heating system with all its components;

Figure 5 depicts the heating element mounted on a 3D Printer's fabrication heat;

DETAILED DESCRIPTION

This high temperature module has two classification, namely; 1) heating and maintaining a "hot" environment up to forty degrees Celsius (40 °C), and 2) heating and maintaining a "hot" environment up to five hundred degrees Celsius (500 °C).

The first classification of heating and maintaining a "hot" environment up to forty degrees Celsius (40 °C) is and will be referred to in this article as the cell-friendly temperature. Human cells prefer an environment where the temperature is 37 °C, however, some cells can survive an environment where is about 40 °C. Due to this, the first classification is referred to the cell-friendly temperature.

The second classification of heating and maintaining a "hot" environment up to five hundred degrees Celsius (500 °C) is and will be referred to the hot-melt temperature. When using this process of the high temperature module there will not be any cell in the fabrication system. Any living organism used with temperature setting of the hot-melt settings will die. The hot-melt processes are primarily used to change the viscosity of the bio-polymer within the fabrication system, rendering it printable. Most bio-polymer are rigid at ambient temperature and cannot be printed on a biological printer. Some processes used to make these material printable are chemical synthesis. Most chemical process will change the material properties, or even worst, introduce hard toxins, making it useless for the use of cells. Introducing a hot-melt system directly to the fabrication system provides new incentives to use a wider range of material to fabricate more complex physiologically relevant tissue constructs. Figure 1 and Figure 2 shows two designs of the heating elements. Figure 1 is a round heating element with the heating wires enclosed within its walls. This design is best for fast heating, high heating, and limited space applications. Figure 2 is designed with a ceramic heating wire that conducts heats thru the heating block. This design is for relatively low heating applications. Figure 3 shows the system configuration and the closed-loop feedback PID controller.

The design and operation of the cell-friendly and hot-melt high temperature module is the same. The major difference between the two, is the range of operational temperature. This high temperature module for a 3D biological printer's deposition system has a proportional-integral-derivative (PID) temperature control unit,

thermocouple, relay system, heating element, heating body, and mounting apparatus.

The PID temperature control unit is integrated with the biological printer such that all settings and processes can be controlled by the end-user and/or with the printer's control system. The PID system provides a unique feedback control system that reduces error and over-shooting temperature settings. Over-shooting temperature can create an environment that is too hot, hence causing cell dead or burning the material in the fabrication system. Coupled with the PID system is the relay system. Together these two systems provides and maintain thermal equilibrium (set by the end user). Figure 4 shows the heating elements and its system components.

The heating element is designed based on the operator's main objectives. If the desire is for hot-melt, a high wattage heating element will be used. If the desire if for cell- friendly temperature, a low wattage heating element will be used. The heating element is a thermal electric system that generates heat from electricity. This heating element is place inside the heating body where it heats the heating body. The heating body will conduct and uniformly transfer and maintain the heat (energy) onto the fabrication system. The heating body is fabrication from high conductive bio-compatible material. Also on the heating body is a thermocouple. The thermocouple reports current conditions about the heating body back to the PID controller. The thermocouple provides real-time temperature monitoring. To maintain a tight fit on the fabrication system, a mounting apparatus is used. Figure 5 shows an image of the heating element mounted onto the fabrication head of an existing 3D cell printer.

Claims

I . A method of changing and maintain the temperature within a 3D biological printer's fabrication system of at least one degrees Celsius (1 °C) above ambient temperature.

2. The method of claim 1, provides a cell-friendly environment (temperature of up to 40 °C).

3. The method of claim 1, provides a hot-melt environment (temperature of up to 500 °C).

4. The method of claim 1, wherein the extruded bioactive filament maintains cell

viability of at least 70%.

5. The method of claim 1, wherein the extruded bioactive filament includes one or more selected from the group consisting of: a polymer, a solution, a cell-lade solution, a chemically reactive solution, an aqueous solution, sodium alginate solutions, a sacrificial support material, a cell, alginate, a cross-linker, a cross-linking solution, a calcium chloride solution, and a hydrogel.

6. The method of claim 1, wherein the extruded bioactive filament is produced by

uniform mass flow rate.

7. The method of claim 1, wherein the extruded bioactive filament is produced by a gradient mass flow rate.

8. The method of claim 1, wherein the extruded bioactive filament is produced by

backwards mass flow rate.

9. The method of claim 1, wherein the extruded bioactive filament in-part comprised of one or more living cells.

10. The method of claim 1, wherein the extruded bioactive filament has no living

biologies.

I I . The method of claim 1, wherein the extruded bioactive filament is symmetrical along a longitudinal axis

12. The method of claim 1, wherein the extruded bioactive filament is asymmetrical along a longitudinal axis.

13. The method of claim 1, wherein the extruded bioactive filament has one-dimensional pattern.

14. The method of claim 1, wherein the extruded bioactive filament has two-dimensional pattern.

15. The method of claim 1, wherein the extruded bioactive filament has three- dimensional pattern.

16. The method of claim 1, wherein the extruded bioactive filament has a largest cross- sectional dimension less than about 1 mm.

17. The method of using one of more fabrication head using the method in claim 1 : producing methods of claim 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, and 16.

18. The method of claim 1, wherein the bioactive filament is used to produce:

microfluidic tissue constructs, tissue scaffolds, tissue-on-chip, organ-on-a-chip.