Contact: to feature here

Thread Rating:
  • 0 Vote(s) - 0 Average
  • 1
  • 2
  • 3
  • 4
  • 5
Biomimicing tissues using 3-D printed lipid droplets
Biomimicry is a field of biotechnology long present in the scientific world. Copying existing mechanisms present in organisms has been around since technology first evolved, thus in some sense it predates even the notion of biotechnology itself. Technological solutions based on the elegant solutions present in nature range from mimicking hooks of certain plants to produce adhering textiles to mimicking the structure and function of living tissues to produce synthetic copies. One such research has spawned an interesting breakthrough recently. Scientists at Oxford University have come up with a novel approach to building synthetic copies of tissue using another relatively novel technique, the 3-D printer.

A three-dimensional material could, in theory, one day mimic the function and structure of living tissues and cells. The tissue-like material was developed in an Oxford laboratory by Hygan Bayley and associates, using a 3-D printer to “print” thousands of tiny water droplets into a layer of lipids, inciting the lipids to array around the water droplets, creating a cell-like structure. Further, they have figured out how to inject different biochemical solutions into those droplets, and insert proteins into the lipid layers, furthering the mimicking potential. These inserted proteins can form pores, and connect the water droplets within the layer, thus establishing a kind of “cellular” communication. Then, they printed several different types of droplets, colored differently and with different biochemical solutions and concentrations, establishing a “realistic” copy of a tissue. As a finishing touch, they made the tissue move and contract, forming a closing and opening flower-like structure.

These same authors, in an earlier publication, described a similar network of water droplets encapsulated within a layer of oil, forming lipid droplets which adhere to one-another and assemble to form a lipid bilayer reminiscent of a cellular membrane on the surface of the solution. They named them “multisomes”. These droplets could then form semi-permanent pores to allow cellular communication. This theory was now proven, and improved upon by actually printing the fake tissue and forming communicating, functioning “tissues”.

This new approach can be used in drug delivery systems, as scaffolding for cellular regrowth or even to interface and replace damaged tissues, the scientist propose.

The scientist custom built a 3-D printer for this job, as no commercially available printer had the precision required for this job. Then they mixed batches of biochemicals and injected them into the lipid layer. The lipid droplets, or multisomes, can be released by changing the Ph, temperature or chemical content of the surrounding solution. The printed network of droplets, after printing, is moved on to a mobile tray, and adhering droplets are separated by a single thin membrane, inserting pores that connect the content of each droplet. So formed structures have shown several interesting traits, for example the ability to contract and move by changing the volume of a part of the cells, or the ability to transfer and conduct an impulse, just like nerve cells.

By now, the team has created tissues containing up to 35000 individual droplets, but as Bayley states: “The amount of integrated cells is limited only by time and money”. In their experiments they used only two different kinds of droplets, but up to fifty can be used without affecting the integrity of the created tissue.

In an interesting setup, the researchers used two kinds of droplets, differently colored, and injected different concentrations of salt in the two different groups. Then the two different types of droplets were integrated into two separate layers, who were then combined to form a bilayer, with one type of cells comprising the upper layer and the other the bottom one. The droplets formed petal like structures, resembling a flower. By opening and closing pored between then, they were able to use the concentration gradient to mimic osmotic pressure in cells and made the bilayer contract. The petals of the lipid droplet flower closed and opened, mimicking the closing and opening of a flower.

Gabriel Villar of Oxford University's department of chemistry, the inventor of the 3D printer used in the research stated, “We have created a scalable way of producing a new type of soft material. The printed structures could in principle employ much of the biological machinery that enables the sophisticated behavior of living cells and tissues.”

G. Villar, A. D. Graham and H. Bayley. A tissue-like printed material. Science. Vol. 340, April 5, 2013, p.48. doi: 10.1126/science.1229495
Like Post Reply

Users browsing this thread:
1 Guest(s)

Biomimicing tissues using 3-D printed lipid droplets00