Corporate Banner
Satellite Banner
Scientific Communities
Become a Member | Sign in
Home>News>This Article

Slow-Release "Jelly" Novel Drug Deliverer

Published: Wednesday, January 30, 2013
Last Updated: Wednesday, January 30, 2013
Bookmark and Share
Biomedical engineers have developed a novel method to overcome the major hurdles facing a promising new class of peptide drugs to treat diseases such as diabetes and cancer.

For example, the hormone insulin is a peptide, which regulates the metabolism of carbohydrates in the body and is used as a drug to treat diabetes. There are more than 40 peptide drugs approved for use in humans and more than 650 are being tested in clinical studies.

However, despite their effectiveness, these peptide drugs cannot achieve their full potential for a number of reasons. First, they are rapidly degraded in the blood stream. A second major drawback is their rapid clearance from the body, which requires multiple, frequent injections. Because of this, their concentrations in the blood can rise precipitously right after injection and fall dramatically soon thereafter, causing unwanted side effects for patients.

One popular method to solve this problem involves loading peptide drugs into polymer microspheres that are injected under the skin and slowly degrade and release the peptide drug.   Microsphere-release technology has proven useful, but has many issues related to its manufacture and ease of patient use, the researchers said.

“We wanted to know if we could create a system that does what the polymer microspheres do, but gets rid of the microspheres and is more patient friendly,” said Ashutosh Chilkoti, Theo Pilkington Professor of Biomedical Engineering at Duke’s Pratt School of Engineering.

The new approach involves making a “fusion protein” that consists of multiple copies of a peptide drug fused to a polymer that makes the fusion protein sensitive to body heat. The fusion molecule is a liquid in a syringe but transforms into a “jelly” when injected under the skin.  Enzymes in the skin attack the depot and liberate copies of the peptide, which provides a constant and controllable release of drug over time.

Miriam Amiram, former Chilkoti graduate student and first author on the paper, dubbed the new delivery system POD, for protease-operated depot.

In the latest experiments, published on-line in the journal Proceedings of the National Academy of Science, the researchers fused glucagon-like peptide-1 (GLP-1), a hormone that regulates the release of insulin, with a genetically engineered heat sensitive polymer to create the POD.

“Remarkably, a single injection of the GLP-1 POD was able to reduce blood glucose levels in mice for up to five days, which is 120 times longer than an injection of the peptide alone,” Chilkoti said.  “For a patient with type 2 diabetes, it would be much more desirable to inject such a drug once a week or once a month rather than once or twice a day.

“Additionally, this approach avoids the peaks and valleys of drug concentrations that these patients often experience,” Chilkoti said.

Unlike peptide-loaded microspheres, PODs are also easy to manufacture, as the peptide drug and the heat-sensitive polymer are all made of amino acids, so that they are expressed as one long stretch of amino acids in bacteria.

“Our experiments demonstrate that this new delivery system provides the first entirely genetically encoded alternative to existing peptide drug encapsulation approaches for sustained delivery of peptide drugs,” Chilkoti said.

Further Information
Access to this exclusive content is for Technology Networks Premium members only.

Join Technology Networks Premium for free access to:

  • Exclusive articles
  • Presentations from international conferences
  • Over 2,600+ scientific posters on ePosters
  • More Than 3,800+ scientific videos on LabTube
  • 35 community eNewsletters

Sign In

Forgotten your details? Click Here
If you are not a member you can join here

*Please note: By logging into you agree to accept the use of cookies. To find out more about the cookies we use and how to delete them, see our privacy policy.

Related Content

Molecular ‘Kiss Of Death’ Flags Pathogens For Destruction
Researchers have discovered that our bodies mark pathogen-containing vacuoles for destruction by using a molecule called ubiquitin, commonly known as the "kiss of death."
Wednesday, September 30, 2015
Newly Identified Biochemical Pathway Could Be Target for Insulin Control
Researchers at Duke Medicine and the University of Alberta are reporting the identification of a new biochemical pathway to control insulin secretion from islet beta cells in the pancreas, establishing a potential target for insulin control.
Tuesday, September 29, 2015
Protein Structures Assemble and Disassemble On Command
Gene sequences may enable control of building bio-structures.
Wednesday, September 23, 2015
Molecular Tinkering Doubles Cancer Drug’s Efficacy
Researchers have packaged a widely used cancer drug into nanoparticles, more than doubling its effectiveness at destroying tumors.
Thursday, August 06, 2015
Researchers Learn To Measure Aging Process In Young Adults
Biological measures may be combined to determine whether people are aging faster or slower than their peers.
Tuesday, July 07, 2015
Outsmarting HIV With Vaccine Antigens Made to Order
AIDS vaccine researchers may be one step closer to outwitting HIV, thanks to designer antibodies and antigens made to order at Duke University.
Thursday, July 02, 2015
Animals’ Genomic Buffers May Help Humans
Researchers at Duke University School of Medicine and Brigham and Women’s Hospital, Harvard Medical School have identified a mechanism that explains why some mutations can be disease-causing in one genome but benign in another.
Wednesday, July 01, 2015
New Gene Influences Apple or Pear Shape, Risk of Future Disease
Duke researchers have discovered that a gene called Plexin D1 controls both where fat is stored and how fat cells are shaped.
Tuesday, March 24, 2015
Boy or Girl? Lemur Scents Have the Answer
A new study finds that a pregnant lemur’s signature scent depends in part on whether she’s carrying a girl or a boy.
Friday, February 27, 2015
Duke Awarded $10.4 Million Contract To Continue Developing Radiation Test
The blood test will be able to tell in hours how much radiation a person has absorbed from a nuclear incident.
Friday, February 20, 2015
Bacterial Defense Mechanism Targets Duchenne Muscular Dystrophy
Gene therapy approach could treat 60 percent of Duchenne Muscular Dystrophy patients.
Friday, February 20, 2015
First Contracting Human Muscle Grown in Laboratory
Researchers at Duke University report the first lab-grown, contracting human muscle, which could revolutionize drug discovery and personalized medicine.
Wednesday, January 14, 2015
Drugs to Block Angiogenesis Could Provide New Treatment for TB
Blood supply gives invaders oxygen and a way out.
Monday, November 24, 2014
Gene Required for Recovery from Bacterial Infection Identified
Duke researchers have uncovered the genes that are normally activated during recovery from bacterial infection in the C. elegans worm. The finding could be key to new antibiotics and countering auto-immune disorders.
Monday, October 27, 2014
Nanoparticles Accumulate Quickly in Wetland Sediment
Aquatic food chains might be harmed by molecules "piggybacking" on carbon nanoparticles.
Friday, October 10, 2014
Scientific News
Genetic Defences of Bacteria Don’t Aid Antibiotic Resistance
Genetic responses to the stresses caused by antibiotics don’t help bacteria to evolve a resistance to the medications, according to a new study by Oxford University researchers.
Detecting HIV Diagnostic Antibodies with DNA Nanomachines
New research may revolutionize the slow, cumbersome and expensive process of detecting the antibodies that can help with the diagnosis of infectious and auto-immune diseases such as rheumatoid arthritis and HIV.
Snapshot Turns T Cell Immunology on its Head
New research may have implications for 1 diabetes sufferers.
Tolerant Immune System Increases Cancer Risk
Researchers have found that individuals with high immunoCRIT ratios may have an increased risk of developing certain cancers.
Developing a Gel that Mimics Human Breast for Cancer Research
Scientists at the Universities of Manchester and Nottingham have been funded to develop a gel that will match many of the biological structures of human breast tissue, to advance cancer research and reduce animal testing.
Cell's Waste Disposal System Regulates Body Clock Proteins
New way to identify interacting proteins could identify potential drug targets.
New Approach to Treating Heparin-induced Blood Disorder
A potential treatment for a serious clotting condition that can strike patients who receive heparin to treat or prevent blood clots may lie within reach by elucidating the structure of the protein complex at its root.
Horse Illness Shares Signs of Human Disease
Horses with a rare nerve condition have similar signs of disease as people with conditions such as Alzheimer’s, a study has found.
How a Molecular Motor Untangles Protein
Diseases such as Alzheimer’s, Parkinson’s and prion diseases, all involve “tangled” proteins.
Compound Doubles Up On Cancer Detection
Researchers have found that tagging a pair of markers found almost exclusively on a common brain cancer yields a cancer signal that is both more obvious and more specific to cancer.
Scroll Up
Scroll Down
Skyscraper Banner

Skyscraper Banner
Go to LabTube
Go to eposters
Access to the latest scientific news
Exclusive articles
Upload and share your posters on ePosters
Latest presentations and webinars
View a library of 1,800+ scientific and medical posters
2,600+ scientific and medical posters
A library of 2,500+ scientific videos on LabTube
3,800+ scientific videos