Showing posts with label Bioprinting. Show all posts
Showing posts with label Bioprinting. Show all posts

Monday, 15 October 2018

Discovery of a new Printing Technology Making use of Sound Waves

Printing Technology
Engineers from the University of Harvard have come out with a new printing technology that makes use of sound waves. This is a great revolution in printing where the sound waves control the droplet flow of highly viscous liquids. In other words, the new printing Technology involves a printer which uses sound to print with the help of tiny droplets of highly viscous liquids.

The new printing technology will help in the manufacturing of biopharmaceuticals and bioprinting. Here they use biopolymer and cell-laden solutions which are 100 times denser than water.

According to Jennifer Lewis, a senior author and professor of Biologically Inspired Engineering at Harvard University, the new printing technology that they have created helps printing in a drop-on-demand manner.

In the new Printing Technology, how the liquid can be manipulated with the help of sound waves: 

We see in Inkjet printing which patterns liquid droplets, the liquids are about 10 times more viscous than water. The researchers are far more interested in liquids that are more viscous. In the case of biopharmaceuticals and bioprinting, biopolymer and cell-laden solutions are about 100 times more viscous than water. There are some sugar-based biopolymers which have the same viscosity as honey which is about 25,000 times more viscous than water. Viscosity of fluids is influenced by temperature and composition changes. With the result, controlling the droplet size becomes difficult and hence it is not possible to optimize the printing parameters.

The researchers therefore wanted to develop a new printing technology independent of the viscosity of the fluid. They thus turned their attention to using sound waves. When we consider a liquid under gravitational force, the droplet size is large and the flow of the droplet is difficult to control.

The researchers have thus turned to generating sound waves in order to enhance drop formation. Pressure waves have been used to defy the earth’s gravitational force, as is seen in Acoustic Levitation. These same sound waves are being used by the researchers to assist gravity and the new technology adopted is known as acoustophoretic printing.

The researchers have built a sub-wavelength acoustic resonator that can generate a highly confined acoustic field that can pull a force that is 100 times more than the gravitational force at the tip of the printer nozzle. In this new printing technology, the controlled force then pulls each droplet from the nozzle on attaining a specific size. It is then ejected on the area for printing. If the amplitude of the sound waves is high then the droplet size is small, irrespective of the fluid’s viscosity.

The new Printing Technology can have a wider scope: 

The new printing Technology was carried out on different materials like honey, stem-cell inks, biopolymers, optical resins and liquid metals. It was seen that the sound waves do not travel through the droplet and hence the method was safe to use even in the case of sensitive living cells or proteins. They hope that the new printing technology can help in the manufacture of new biopharmaceuticals, cosmetics and food.