Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Tufts University bioengineers discover secret of spider, silkworm fiber strength

28.08.2003


Findings could drive new tissue engineering applications, organ repair and high-strength materials



Tufts University bioengineers have discovered how spiders and silkworms are able to spin webs and cocoons made of incredibly strong fibers. The answer lies in how they control the silk protein solubility and structural organization in their glands.

"This finding could lead to the development of processing methods resulting in new high-strength and high-performance materials used for biomedical applications, and protective apparel for military and police forces," said David Kaplan, professor and chair of biomedical engineering, and director of Tufts’ Bioengineering Center.


"We identified key aspects of the process that should provide a roadmap for others to optimize artificial spinning of silks as well as in improved production of silks in genetically engineered host systems such as bacteria and transgenic animals," said Kaplan, also a professor of chemical and biological engineering.

He and former postdoctoral fellow Hyoung-Joon Jin published their findings, "Mechanism of Processing of Silks in Insects and Spiders," in the Aug. 28 issue of the international science journal Nature.

The research was funded with $1 million from the National Institutes of Health Dental Institute and $200,000 from the U.S. Air Force Office of Scientific Research. Kaplan collaborated with Tufts colleagues across the University – from chemical, biological and biomedical to the veterinary and dental schools.

Silk is the strongest natural fiber known, but its strength has yet to be replicated in a laboratory. One reason may be the previous lack of understanding how spiders and silkworm process the silk.

The Tufts team has identified the way that spiders and silkworms control the solubility, concentration and structure of the proteins in their glands that spin the silk.

According to Kaplan, silk proteins are organized into pseudo-micelle or soap-like structures that form globular and gel states during processing in the glands. This semi-stable state, with sufficiently entrapped water and liquid crystalline structures, prevents the proteins from crystallizing too early, until the spinning process.

The structures formed in the process can be easily converted artificially into fibers with physical shear (moving the silk gel between two plates of glass) or during fiber spinning in the native process. The control of water content and structure development are essential because premature crystallization of the protein could cause a permanent blockage of the spinning system, leading to catastrophic consequences for the spider or silkworm.

This process, when combined with the novel polymer design features in silk proteins, retains sufficient water to keep the protein soluble, while allowing the protein to self-organize and reach spinnable concentrations. Achieving sufficient concentration of protein is key to the proper spinning of fibers and to the spider’s and silkworm’s survival.

Kaplan says this new insight into silk processing could result in:


New high-strength and high-performance materials such as sports equipment, hiking gear and protective clothing for law enforcement;

New biomaterial applications for cell growth in tissue engineering, as well as general biomaterial needs for tissue and organ repair;

Environmentally sound processes to generate fibers and films from these types of polymers, since the entire process occurs in water.
"Kaplan’s research is distinctive because it addresses a fundamental problem common to all prior research in this field," said Jamshed Bharucha, Tufts provost and senior vice president.

In 2002, Kaplan and his team of researchers from Tufts’ schools of engineering and medicine developed a tissue engineering strategy to repair one of the world’s most common knee injuries -- ruptured anterior cruciate ligaments (ACL) -- by mechanically and biologically engineering new ones using silk scaffolding for cell growth. This ligament at the center of the knee connects the leg to the thigh and stabilizes the knee joint in leg extension and flexion.

Approximately 200,000 ACL surgeries were done in the U.S. in 2001, costing an estimated $3.5 billion, plus another $200 million for subsequent therapy. The costs associated with surgery can range from $10,000 to $25,000 per procedure, and up to $1,200 in physical therapy.


Tufts University, located on three Massachusetts campuses in Boston, Medford/Somerville, and Grafton, and in Talloires, France, is recognized among the premier research universities in the United States. Tufts enjoys a global reputation for academic excellence and for the preparation of students as leaders in a wide range of professions. A growing number of innovative teaching and research initiatives span all Tufts campuses, and collaboration among the faculty and students in the undergraduate, graduate and professional programs across the University’s eight schools is widely encouraged.


Craig LeMoult | EurekAlert!
Further information:
http://www.tufts.edu/

More articles from Life Sciences:

nachricht Rainbow colors reveal cell history: Uncovering β-cell heterogeneity
22.09.2017 | DFG-Forschungszentrum für Regenerative Therapien TU Dresden

nachricht The pyrenoid is a carbon-fixing liquid droplet
22.09.2017 | Max-Planck-Institut für Biochemie

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: The pyrenoid is a carbon-fixing liquid droplet

Plants and algae use the enzyme Rubisco to fix carbon dioxide, removing it from the atmosphere and converting it into biomass. Algae have figured out a way to increase the efficiency of carbon fixation. They gather most of their Rubisco into a ball-shaped microcompartment called the pyrenoid, which they flood with a high local concentration of carbon dioxide. A team of scientists at Princeton University, the Carnegie Institution for Science, Stanford University and the Max Plank Institute of Biochemistry have unravelled the mysteries of how the pyrenoid is assembled. These insights can help to engineer crops that remove more carbon dioxide from the atmosphere while producing more food.

A warming planet

Im Focus: Highly precise wiring in the Cerebral Cortex

Our brains house extremely complex neuronal circuits, whose detailed structures are still largely unknown. This is especially true for the so-called cerebral cortex of mammals, where among other things vision, thoughts or spatial orientation are being computed. Here the rules by which nerve cells are connected to each other are only partly understood. A team of scientists around Moritz Helmstaedter at the Frankfiurt Max Planck Institute for Brain Research and Helene Schmidt (Humboldt University in Berlin) have now discovered a surprisingly precise nerve cell connectivity pattern in the part of the cerebral cortex that is responsible for orienting the individual animal or human in space.

The researchers report online in Nature (Schmidt et al., 2017. Axonal synapse sorting in medial entorhinal cortex, DOI: 10.1038/nature24005) that synapses in...

Im Focus: Tiny lasers from a gallery of whispers

New technique promises tunable laser devices

Whispering gallery mode (WGM) resonators are used to make tiny micro-lasers, sensors, switches, routers and other devices. These tiny structures rely on a...

Im Focus: Ultrafast snapshots of relaxing electrons in solids

Using ultrafast flashes of laser and x-ray radiation, scientists at the Max Planck Institute of Quantum Optics (Garching, Germany) took snapshots of the briefest electron motion inside a solid material to date. The electron motion lasted only 750 billionths of the billionth of a second before it fainted, setting a new record of human capability to capture ultrafast processes inside solids!

When x-rays shine onto solid materials or large molecules, an electron is pushed away from its original place near the nucleus of the atom, leaving a hole...

Im Focus: Quantum Sensors Decipher Magnetic Ordering in a New Semiconducting Material

For the first time, physicists have successfully imaged spiral magnetic ordering in a multiferroic material. These materials are considered highly promising candidates for future data storage media. The researchers were able to prove their findings using unique quantum sensors that were developed at Basel University and that can analyze electromagnetic fields on the nanometer scale. The results – obtained by scientists from the University of Basel’s Department of Physics, the Swiss Nanoscience Institute, the University of Montpellier and several laboratories from University Paris-Saclay – were recently published in the journal Nature.

Multiferroics are materials that simultaneously react to electric and magnetic fields. These two properties are rarely found together, and their combined...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

“Lasers in Composites Symposium” in Aachen – from Science to Application

19.09.2017 | Event News

I-ESA 2018 – Call for Papers

12.09.2017 | Event News

EMBO at Basel Life, a new conference on current and emerging life science research

06.09.2017 | Event News

 
Latest News

Rainbow colors reveal cell history: Uncovering β-cell heterogeneity

22.09.2017 | Life Sciences

Penn first in world to treat patient with new radiation technology

22.09.2017 | Medical Engineering

Calculating quietness

22.09.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>