Toggle light / dark theme

Scalability and device integration have been prevailing issues limiting our ability in harnessing the potential of small-diameter conducting fibers. We report inflight fiber printing (iFP), a one-step process that integrates conducting fiber production and fiber-to-circuit connection. Inorganic (silver) or organic {PEDOT: PSS [poly(3,4-ethylenedioxythiophene) polystyrene sulfonate]} fibers with 1- to 3-μm diameters are fabricated, with the fiber arrays exhibiting more than 95% transmittance (350 to 750 nm). The high surface area–to–volume ratio, permissiveness, and transparency of the fiber arrays were exploited to construct sensing and optoelectronic architectures. We show the PEDOT: PSS fibers as a cell-interfaced impedimetric sensor, a three-dimensional (3D) moisture flow sensor, and noncontact, wearable/portable respiratory sensors. The capability to design suspended fibers, networks of homo cross-junctions and hetero cross-junctions, and coupling iFP fibers with 3D-printed parts paves the way to additive manufacturing of fiber-based 3D devices with multilatitude functions and superior spatiotemporal resolution, beyond conventional film-based device architectures.

Small-diameter conducting fibers have unique morphological, mechanical, and optical properties such as high aspect ratio, low bending stiffness, directionality, and transparency that set them apart from other classes of conducting, film-based micro/nano structures (1–3). Orderly assembling of thin conducting fibers into an array or three-dimensional (3D) structures upscales their functional performance for device coupling. Developing new strategies to control rapid synthesis, patterning, and integration of these conducting elements into a device architecture could mark an important step in enabling new device functions and electronic designs (4, 5). To date, conducting micro/nanoscaled fibers have been produced and assembled in a number of ways, from transferring of chemically grown nanofibers/wires (6, 7), writing electrohydrodynamically deposited lines (8, 9), to drawing ultralong fibers (10, 11), wet spinning of fibers (12–14), and 2D/3D direct printing (15–18).

Researchers at the National Institute of Standards and Technology (NIST) have developed a new method of 3D-printing gels and other soft materials. Published in a new paper, it has the potential to create complex structures with nanometer-scale precision. Because many gels are compatible with living cells, the new method could jump-start the production of soft tiny medical devices such as drug delivery systems or flexible electrodes that can be inserted into the human body.

A standard 3D printer makes solid structures by creating sheets of material — typically plastic or rubber — and building them up layer by layer, like a lasagna, until the entire object is created.

Using a 3D printer to fabricate an object made of gel is a “bit more of a delicate cooking process,” said NIST researcher Andrei Kolmakov. In the standard method, the 3D printer chamber is filled with a soup of long-chain polymers — long groups of molecules bonded together — dissolved in water. Then “spices” are added — special molecules that are sensitive to light. When light from the 3D printer activates those special molecules, they stitch together the chains of polymers so that they form a fluffy weblike structure. This scaffolding, still surrounded by liquid water, is the gel.

In the coming 2020s, the world of medical science will make some significant breakthroughs. Through brain implants, we will have the capability to restore lost memories.

~ The 2020s will provide us with the computer power to make the first complete human brain simulation. Exponential growth in computation and data will make it possible to form accurate models of every part of the human brain and its 100 billion neurons.

~ The prototype of the human heart was 3D printed in 2019. By the mid- 2020s, customized 3D- printing of major human body organs will become possible. In the coming decades, more and more of the 78 organs in the human body will become printable.

…As we enter into the next few decades, we will have the technologies that grant us the possibility of immortality, albeit one that is highly subjective.

With our ability to 3D print new body organs, our ability to use nanotechnology in fighting death at cellular levels, our ability to use CRISPR or other gene-editing technology to rewrite our definition of humans and even our ability to capture and extend our consciousness beyond the confines of the biological weakness of our human bodies — immortality may be within reach of our fingers as depicted in the painting of Michelangelo.

Researchers at the National Institute of Standards and Technology (NIST) have developed a new method of 3D-printing gels and other soft materials. Published in a new paper, it has the potential to create complex structures with nanometer-scale precision. Because many gels are compatible with living cells, the new method could jump-start the production of soft tiny medical devices such as drug delivery systems or flexible electrodes that can be inserted into the human body.

A standard 3D printer makes solid structures by creating sheets of material—typically plastic or rubber—and building them up layer by layer, like a lasagna, until the entire object is created.

Using a 3D printer to fabricate an object made of gel is a “bit more of a delicate cooking process,” said NIST researcher Andrei Kolmakov. In the standard method, the 3D printer chamber is filled with a soup of long-chain polymers—long groups of molecules bonded together—dissolved in water. Then “spices” are added—special molecules that are sensitive to light. When light from the 3D printer activates those special molecules, they stitch together the chains of polymers so that they form a fluffy weblike . This scaffolding, still surrounded by , is the gel.

Volumetric Bioprinting


Recreating human body parts using a 3D printer. This is possible in the Netherlands with the new bioprinter developed by Utrecht University and UMC Utrecht. This printer can be used to make models of organs or bones, amongst other things. These printed models can be made up of living cells on which medication can be tested, for instance.

Conventional 3D printers work by stacking plastic layers on top of each other. This build-up of layers creates a three-dimensional figure. There are already countless possibilities with these standard 3D printers. Science has been looking for years at how this technique can be applied across different areas.

Printing living cells

Researchers from China continue in the quest to improve methods for bone regeneration, publishing their findings in “Cryogenic 3D printing of dual-delivery scaffolds for improved bone regeneration with enhanced vascularization.”

A wide range of projects have emerged regarding new techniques for bone regeneration—especially in the last five years as 3D printing has become more entrenched in the mainstream and bioprinting has continued to evolve. Bone regeneration is consistently challenging, and while bioprinting is still relatively new as a field, much impressive progress has been made due to experimentation with new materials, nanotubes, and innovative structures.

Cell viability is usually the biggest problem. Tissue engineering, while becoming much more successful these days, is still an extremely delicate process as cells must not only be grown but sustained in the lab too. For this reason, scientists are always working to improve structures like scaffolds, as they are responsible in most cases for supporting the cells being printed. In this study, the authors emphasize the need for both “excellent osteogenesis and vascularization” in bone regeneration.

A high-power laser, optimized optical pathway, a patented adaptive resolution technology, and smart algorithms for laser scanning have enabled UpNano, a Vienna-based high-tech company, to produce high-resolution 3D-printing as never seen before.

“Parts with nano- and microscale can now be printed across 12 orders of magnitude—within times never achieved previously. This has been accomplished by UpNano, a spin-out of the TU Wien, which developed a high-end two-photon polymerization (2PP) 3D-printing system that can produce polymeric parts with a volume ranging from 100 to 1012 cubic micrometers. At the same time the printer allows for a nano- and microscale resolution,” the company said in a statement.

Recently the company demonstrated this remarkable capability by printing four models of the Eiffel Tower ranging from 200 micrometers to 4 centimeters—with perfect representation of all minuscule structures within 30 to 540 minutes. With this, 2PP 3D-printing is ready for applications in R&D and industry that seemed so far impossible.