Navigation Links
Implantable silk optics multi-task in the body
Date:11/28/2012

MEDFORD/SOMERVILLE, Mass. (November 28, 2012) Tufts University School of Engineering researchers have demonstrated silk-based implantable optics that offer significant improvement in tissue imaging while simultaneously enabling photo thermal therapy, administering drugs and monitoring drug delivery. The devices also lend themselves to a variety of other biomedical functions.

Biodegradable and biocompatible, these tiny mirror-like devices dissolve harmlessly at predetermined rates and require no surgery to remove them.

The technology is the brainchild of a research team led by Fiorenzo Omenetto, Frank C. Doble Professor of Engineering at Tufts. For several years, Omenetto; David L. Kaplan, Stern Family Professor of Biomedical Engineering and Biomedical Engineering chair, and their colleagues have been exploring ways to leverage silk's optical capabilities with its capacity as a resilient, biofriendly material that can stabilize materials while maintaining their biochemical functionality.

The technology is described in the paper "Implantable Multifunctional Bioresorbable Optics," published in the Proceedings of the National Academy of Sciences online Early Edition the week of November 12, 2012.

"This work showcases the potential of silk to bring together form and function. In this case an implantable optical form -- the mirror -- can go beyond imaging to serve multiple biomedical functions," Omenetto says.

Turning Silk into Mirrors

To create the optical devices, the Tufts bioengineers poured a purified silk protein solution into molds of multiple micro-sized prism reflectors, or microprism arrays (MPAs). They pre-determined the rates at which the devices would dissolve in the body by regulating the water content of the solution during processing. The cast solution was then air dried to form solid silk films in the form of the mold. The resulting silk sheets were much like the reflective tape found on safety garments or on traffic signs.

When implanted, these MPAs reflected back photons that are ordinarily lost with reflection-based imaging technologies, thereby enhancing imaging, even in deep tissue.

The researchers tested the devices using solid and liquid "phantoms" (materials that mimic the scattering that occurs when light passes through human tissue). The tiny mirror-like devices reflected substantially stronger optical signals than implanted silk films that had not been formed as MPAs.

Preventing Infection, Fighting Cancer

The Tufts researchers also demonstrated the silk mirrors' potential to administer therapeutic treatments.

In one experiment, the researchers mixed gold nanoparticles in the silk protein solution before casting the MPAs. They then implanted the gold-silk mirror under the skin of mice. When illuminated with green laser light, the nanoparticles converted light to heat. Similar in-vitro experiments showed that the devices inhibited bacterial growth while maintaining optical performance.

The team also embedded the cancer-fighting drug doxorubicin in the MPAs. The embedded drug remained active even at high temperatures (60 degree C), underscoring the ability of silk to stabilize chemical and biological dopants.

When exposed to enzymes in vitro, the doxorubicin was released as the mirror gradually dissolved. The amount of reflected light decreased as the mirror degraded, allowing the researchers to accurately assess the rate of drug delivery.

"The important implication here is that using a single biofriendly, resorbable device one could image a site of interest, such as a tumor, apply therapy as needed and then monitor the progress of the therapy," says Omenetto.


'/>"/>

Contact: Alex Reid
alexander.reid@tufts.edu
617-627-4173
Tufts University
Source:Eurekalert  

Related biology news :

1. Pilot Results Move GHX Closer to Delivery of Healthcare Industrys First Implantable Device Supply Chain Solution
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
Implantable silk optics multi-task in the body
(Date:4/19/2017)... , April 19, 2017 ... its vendor landscape is marked by the presence of ... is however held by five major players - 3M ... these companies accounted for nearly 61% of the global ... leading companies in the global military biometrics market boast ...
(Date:4/13/2017)... MONICA, Calif. , April 13, 2017 ... New York will feature emerging and evolving ... Summits. Both Innovation Summits will run alongside the expo ... of speaker sessions, panels and demonstrations focused on trending ... coast,s largest advanced design and manufacturing event will take ...
(Date:4/11/2017)... 2017 Research and Markets has announced the ... to their offering. ... eye tracking market to grow at a CAGR of 30.37% during ... Market 2017-2021, has been prepared based on an in-depth market analysis ... and its growth prospects over the coming years. The report also ...
Breaking Biology News(10 mins):
(Date:10/11/2017)... ... October 11, 2017 , ... The ... context, enabling overexpression experiments and avoiding the use of exogenous expression plasmids. The ... transformative for performing systematic gain-of-function studies. , This complement to loss-of-function studies, ...
(Date:10/11/2017)... ... 2017 , ... Proscia Inc ., a data solutions ... “Pathology is going digital. Is your lab ready?” with Dr. Nicolas Cacciabeve, Managing ... how Proscia improves lab economics and realizes an increase in diagnostic confidence.* ...
(Date:10/11/2017)... ... October 11, 2017 , ... Disappearing forests and increased emissions are ... 5.5 million people each year. Especially those living in larger cities are affected by ... in one of the most pollution-affected countries globally - decided to take action. , ...
(Date:10/10/2017)... DIEGO, CALIF. (PRWEB) , ... October 10, 2017 , ... ... as part of its corporate rebranding initiative announced today. The bold new look ... its reach, as the company moves into a significant growth period. , It will ...
Breaking Biology Technology: