3D printed hydrogel nanocomposites helps to detoxify the blood like a liver
Researchers at the University of California, San Diego have developed a 3D printed detoxification device, inspired by the human liver to remove dangerous toxins from the blood. The device uses nanoparticles to trap pore-forming toxins that can damage cellular membranes, which are a key factor in illnesses that result from animal bites and stings, and bacterial infections.
Nanoparticles have already been shown to be effective at neutralizing pore-forming toxins in the blood, but if those nanoparticles cannot be effectively digested, they can accumulate in the liver creating a risk of secondary poisoning, especially among patients who are already at risk of liver failure.
The research team led by nanoengineering professor Shaochen Chen, has created a 3D-printed hydrogel matrix to house nanoparticles, forming a device that mimics the structure and function of the liver. It has a larger surface area designed to efficiently sense, attract and trap toxins routed from the blood. The device turns red every time when the toxins are captured.
The device, which is designed to be used outside the body, is in the proof-of-concept stage. In an in vitro study, It completely neutralized pore-forming toxins.
"The concept of using 3D printing to encapsulate functional nanoparticles in a biocompatible hydrogel is novel," said Chen. "This will inspire many new designs for detoxification techniques since 3D printing allows user-specific or site-specific manufacturing of highly functional products," Chen said.
A 3D printed device inspired by the liver (Photo: The University of California)
Dynamic optical projection stereolithography
Chen's biofabrication technology, called dynamic optical projection stereolithography (DOPsL), uses a computer projection system and precisely controlled micromirrors to shine light on a selected area of a solution containing photo-sensitive biopolymers and cells. This photo-induced solidification process forms one layer of solid structure at a time, but in a continuous fashion.
This DOPsL technology can be used to produce the micro- and nanoscale resolution required to print tissues that mimic nature's fine-grained details, including blood vessels, which are essential for distributing nutrients and oxygen throughout the body.
IN 2012, Chen's team demonstrated the DOPsL technology that can fabricate, in mere seconds,microscale three dimensional structures out of soft, biocompatible hydrogels.
Without the ability to print vasculature, an engineered liver or kidney, for example, is useless in regenerative medicine. With DOPsL, Chen's team was able to achieve more complex geometries common in nature such as flowers, spirals and hemispheres. Other current 3D fabrication techniques, such as two-photon photopolymerization, can take hours to fabricate a 3D part.
The project is supported by a four-year, $1.5 million grant from the National Institutes of Health, and a grant from the National Science Foundation.
Their findings were published May 8 in the journal Nature Communications.