Electrical Part 1:
We designed the handheld bioprinter based on the comfortability and ease of use. This was tested based on how comfortable it was to hold the bioprinter and by printing an entire syringe of hydrogel. Based on our tests, the bioprinter could be held comfortably but couldn’t be fully enclosed within one hand. As such, we determined that we could optimize comfortability by rounding the edges to make it easier to hold on the sides.
We tested extrusion by determining if it could extrude the hydrogel smoothly and at a consistent rate throughout the nozzle. Speed could be adjusted through the code by changing the rate of revolution of the stepper motor. Tested at the fastest setting of 15 rpm, extrusion rate was 0.882 mm/s.
Line Test [1]:Accuracy and precision of the bioprinter was tested by printing sketches of sample bioart and comparing expected results to printed products. From this, resolution, precision, and accuracy could be determined.
Due to its high water content, good biocompatibility, controllable mechanical properties, and biodegradability, hydrogels have received extensive attention in tissue engineering fields and additive 3D printing. 3D bioprinting systems, in particular, can create a construct out of a hydrogel containing live cells [2]. Controlling the properties of the bio-ink is one of the requirements of the bioprinting process. This can be accomplished by varying the types of base materials used to make the bio-ink in order to achieve the desired biological and physiological properties in various tissues. Our primary goal is to develop a range of hydrogels with different crosslinking times and ingredient ratios. And applying hydrogels to various syringes to test the best extrusion process. According to our experimental data, the properties of any bio- derived hydrogels can be easily predicted, and thus the printing time can be estimated.
HydrogelsFor the preparation of hydrogels, a novel method was proposed that uses water present in swollen hydrogels as a porogen for shape templates. Crosslinking gelatin with glutaraldehyde in an aqueous solution, followed by rinsing and washing, was used to create biodegradable hydrogels [3]. The aim of our work was to produce hydrogels with various properties. The following steps were used to create our gelatin and GA hydrogels:
Resource Guide to Bio-Art Ethics
Through our interviews, we learned that ethics within the field of bio-art is an important topic. Therefore, we developed a resource guide that discusses the various ethical arguments and discussions that exist regarding the topic of bio-art. This guide was developed in an effort for us to reach our goal of opening up a dialogue about how combining art and science can lead to different perspectives on what power scientists or bio-artists should hold.
Bio-Art Ethical Discussion Slides
Bio-Art Ethical Discussion Slides These slides provide a framework for discussing the ethical implications of bio-art. These slides were developed for use during an outreach event with an older audience. Other teams interested in opening a dialogue about bio-art ethics will be able to use these slides as a basis for discussion.
Outreach Lesson Plan for Younger Audience with Hands-On Activities
This is an outline of a lesson plan that Cornell iGEM developed in order to engage younger students with synthetic biology and STEM in general through hands-on activities that tie together art and science. Since the materials and methods are inexpensive and accessible, other teams may use this lesson plan to develop activities for their own outreach events.
Guide to Starting a Bio-Art Lab
We have developed a guide that compiles all the resources and suggestions needed if a University or group of students/bio-artists are looking to create a bio-art lab at their institution. Though we could not set one up ourselves at Cornell University due to lack of funding and lack of lab space, we created this plan so that any iGEM participants who have the resources available can begin the establishment of their own bio-art labs.
For teams looking to analyze the policy surrounding their bio-art related projects, we created a policy handbook to help direct teams to the proper resources needed to conduct a thorough policy analysis.
We are working to design a novel plasmid that synthesizes the bioink for our 3D printer. Using Gibson Assembly, we will combine the curli nanofiber parts Fibrin knob domain, Fibrin hole domain, csgC, csgE, and csgG with the chromoproteins BBa_K1033902, BBa_K1033910, and BBa_K1033922 (aeBlue, amajLime, asPink respectively). The combination allows for the colorful chromoproteins to be embedded within the curli nanofiber monomers that make up the gel. The complete curli nanofiber mechanism would contain two operons: csgAC and csgEG, with the chromoproteins fused onto the csgA alpha. Also part of the construct will be the inducible promoter BBa_K2042004, the double terminator, BBa_B0014, and the chloramphenicol resistant plasmid backbone pSB1C3 to get only E. coli colonies with the transformed plasmid growing in plates with chloramphenicol. All part numbers listed above can be found in the iGEM parts registry [4].
| Name | Type | Description | Designer | Length(BP) |
|---|---|---|---|---|
| BBa_K4322000 | Coding | Fibrin Knob Domain (Alpha) | Abraham Sinfort | 33 |
| BBa_K4322001 | Coding | Fibrin Hole Domain (Gamma) | Abraham Sinfort | 384 |
| Name | Type | Description | Designer | Length(BP) |
|---|---|---|---|---|
| BBa_K4322002 | Composite | csgAα-asPink fusion protein with glycine-serine linker | Abraham Sinfort | 1395 |
| BBa_K4322003 | Composite | csgAα-aeBlue fusion protein with glycine-serine linker | Abraham Sinfort | 1392 |
| BBa_K4322004 | Composite | csgAα-amajLime fusion protein with glycine-serine linker | Abraham Sinfort | 1386 |
| BBa_K4322005 | Composite | CsgA-α (CsgA-Fibrin Knob Domain Fusion Protein) | Abraham Sinfort | 588 |
| BBa_K4322006 | Composite | CsgA-γ (CsgA-Fibrin Hole Domain Fusion Protein) | Abraham Sinfort | 1011 |
[1] O'Connell C;Ren J;Pope L;Li Y;Mohandas A;Blanchard R;Duchi S;Onofrillo C; (no date) Characterizing Bioinks for extrusion bioprinting: Printability and rheology, Methods in molecular biology (Clifton, N.J.). U.S. National Library of Medicine. Available at: https://pubmed.ncbi.nlm.nih.gov/32207108/ (Accessed: October 6, 2022).
[2] Mikula, K., Skrzypczak, D., Ligas, B., & Witek-Krowiak, A. (2019, May 25). Preparation of hydrogel composites using ca2+ and cu2+ ions as crosslinking agents - SN Applied Sciences. SpringerLink. Retrieved October 6, 2022, from https://link.springer.com/article/10.1007/s42452-019-0657-3
[3] Kang, H.-W., Tabata, Y., & Ikada, Y. (1999, June 17). Fabrication of porous gelatin scaffolds for tissue engineering. Biomaterials. Retrieved October 6, 2022, from https://www.sciencedirect.com/science/article/pii/S0142961299000368?fr=RR-2&ref=pdf_download&rr=727e21a7d98115cf
[4] Registry of Standard Biological Parts. (n.d.). Retrieved from http://parts.igem.org/Main_Page.