{"id":5750,"date":"2018-10-09T02:00:14","date_gmt":"2018-10-09T09:00:14","guid":{"rendered":"https:\/\/athis-consulting.com\/news\/?p=5750"},"modified":"2018-10-10T02:08:20","modified_gmt":"2018-10-10T09:08:20","slug":"harvard-researchers-develop-method-for-3d-printing-with-soundwaves","status":"publish","type":"post","link":"https:\/\/athis-technologies.com\/news\/innovation\/science\/2018\/harvard-researchers-develop-method-for-3d-printing-with-soundwaves\/","title":{"rendered":"Harvard researchers develop method for 3d printing with soundwaves"},"content":{"rendered":"

Researchers from\u00a0Harvard University\u2019s<\/a>\u00a0John A Paulsen School of Engineering and Applied Sciences<\/a>\u00a0(SEAS) in Massachusetts, have created an\u00a0acoustophoretic 3D printing technique which uses sound waves to form drops of a wide range of viscous fluids into additively manufactured structures.<\/p>\n

According to the\u00a0study<\/a>\u00a0published in the latest edition of\u00a0Science Advances,\u00a0<\/i>this new patterning method \u201cwill drive scientific advances in the areas of optics, electronics, biology, and beyond.\u201d<\/p>\n

\u201cOur goal was to take viscosity out of the picture by developing a printing system that is independent from the material properties of the fluid,\u201d said Daniele Foresti, First Author of the paper, the\u00a0Branco Weiss Fellow<\/a>, and Research Associate in Materials Science and Mechanical Engineering at SEAS and the\u00a0Wyss Institute<\/a>.<\/p>\n

A myriad of inks<\/b><\/p>\n

Inkjet 3D printing\u00a0utilizes fluid liquid\u00a0droplets of microliter-to-nanoliter volume to form solids; however, this process is limited to low viscosity inks that are approximately\u00a010 to 100 times higher than the viscosity of water, according to the study. This rules out the 3D printing capabilities of vital biopolymer and cell-laden inks used within\u00a0biopharmaceuticals\u00a0and\u00a03D bioprinting\u00a0as well as sugar-based biopolymers, such as honey, which is 25,000 times more viscous than water.<\/p>\n

Furthermore, the study states that such viscous fluids experience dramatic changes with temperature and composition, making it more challenging to optimize printing parameters to control droplet sizes.<\/p>\n

To enable \u201cmyriad materials\u201d experimentation, the SEAS research team built a subwavelength acoustic resonator capable of generating highly confined acoustic fields which can create pulling forces exceeding \u201c100 times the normal gravitation forces (1G) at the tip of the printer nozzle \u2013 four times the gravitational force on the surface of the sun.\u201d<\/p>\n

\u201cThe idea is to generate an acoustic field that literally detaches tiny droplets from the nozzle, much like picking apples from a tree,\u201d added Foresti.<\/p>\n

\"Honey
Honey drops patterned on a glass substrate using the controlled acoustophoretic printing head. Photo via Daniele Foresti & Jennifer A. Lewis\/Harvard University<\/figcaption><\/figure>\n

Drip by drip<\/b><\/p>\n

The researchers tested the acoustophoretic 3D printing process on a wide range of materials, including honey to stem-cell inks, a cell-laden collagen solution, a UV-curable optical adhesive, and liquid metals. The controllable force from the custom resonator pulls each droplet off of the \u201cacoustophoretic printing head\u201d with a specified radius from 800\u00b5m to less than 65\u00b5m nozzle, and ejects it toward the printing target.<\/p>\n

The researchers found that the higher the amplitude of the sound waves, the smaller the droplet size, no matter the viscosity of the fluid. In addition, as sound waves do not travel through the droplet, the researchers deemed this method as safe to use with sensitive biological cargo, such as living cells or proteins.<\/p>\n

\u201cOur technology should have immediate impact on the pharmaceutical industry,\u201d said Jennifer Lewis, Senior Author of the paper and the\u00a0Hansjorg Wyss Professor of Biologically Inspired Engineering at SEAS. \u201cHowever, we believe that this will become an important platform for multiple industries[i.e.,\u00a0microfluidics<\/a>\u00a0and\u00a0lab on chip devices<\/a>].\u201d<\/p>\n