3D Printing

3D printing in water opens opportunities in medical research

Can you 3D print in water? According to researchers at the Hebrew University of Jerusalem’s Center for Nanoscience and Nanotechnology, you can. They have developed a photoinitiator for 3D printing in water.

3D printing structures in water has always been challenging due to a lack of water soluble molecules known as photoinitiators — the molecules that induce chemical reactions necessary to form solid printed material by light.

Prof. Uri Banin and Prof. Shlomo Magdassi at the Hebrew University’s Institute of Chemistry have developed an efficient means of 3D printing in water using semiconductor-metal hybrid nanoparticles (HNPs) as the photoinitiators.

Hybrid nanoparticles as photoinitiators. a. Electron microscope image of hybrid nanocrystal. The inset shows a schematic of semiconductor nanorod with a metal tip. b. Bucky ball structure produced by rapid 3D printing in water using HNPs as photoinitiators. c. Spiral printed with HNPs by two photon printer providing high resolution features. Adapted with permission from Pawar et al., Nano Lett. DOI: 10.1021/acs.nanolett.7b01870. Copyright (2017) American Chemical Society.

A key market for 3D printing in water is medical. Such technology opens opportunities for tailored fabrication of medical devices and for printing scaffolds for tissue engineering. For example, the researchers envision personalized fabrication of joint replacements, bone plates, heart valves, artificial tendons and ligaments, and other artificial organ replacements.

Unlike regular photoinitiators, the novel hybrid nanoparticles developed by Prof. Banin and Prof. Magdassi present tunable properties, wide excitation window in the UV and visible range, high light sensitivity, and function by a unique photocatalytic mechanism that increases printing efficiency while reducing the amount of materials required to create the final product. The whole process can also be used in advanced polymerization modalities, such as two photon printers, which allows it to produce high-resolution features.

The professors published a research paper that was featured in the American Chemical Society (ACS) Editor’s Choice peer-reviewed research journal.

Prof. Magdassi is the Enrique Berman Chair in Solar Energy at the Hebrew University. Prof. Banin is the incumbent of the Alfred & Erica Larisch Memorial Chair at the Institute of Chemistry at the Hebrew University.

Researchers involved in this study are affiliated with the Center for Nanoscience and Nanotechnology and The Institute of Chemistry at the Hebrew University of Jerusalem, in Israel, and the Institute of Systems Research and Department of Mechanical Engineering at the University of Maryland, in the United States.

The Hebrew University of Jerusalem
new.huji.ac.il/en