Navigation Links
Probing the promise and perils of nanoparticles

For all its promise, the prospect of using nanoparticles in biomedical applications and consumer products has raised concerns about possible harmful effects of the miniscule materials. Scientists at the University of Michigan are addressing those concerns by investigating how certain kinds of nanoparticles damage cell membranes---enough to cause cell death in some cases---and how the damage can be prevented.

"If you're inventing these sorts of materials, you need to be concerned about their impact," said Mark Banaszak Holl, a U-M professor of chemistry and of macromolecular science and engineering. "We're trying to do both: make important new materials and be excited about what can be done with them, but at the same time, understand what their potential downsides might be." Banaszak Holl and graduate students Pascale Leroueil and Seungpyo Hong will discuss their research at the 229th national meeting of the American Chemical Society in San Diego March 13-17.

In collaboration with other researchers at U-M's Center for Biologic Nanotechnology, Banaszak Holl's lab has been studying nanoparticles known as dendrimers, tiny spheres whose width is ten thousands times smaller than the thickness of a human hair. Dendrimers have shown promise for precisely delivering drugs to their targets inside the body, but high concentrations of these nanoparticles can be toxic. In earlier work, U-M researchers discovered that dendrimers punch nanoscale holes in cell membranes, making the membranes more permeable. At high enough concentrations, they can completely destroy the membranes, killing cells in the process. But the damage can be prevented by engineering dendrimers in particular ways, such as modifying their surfaces to make them neutral instead of charged, the scientists found. And, added Banaszak Holl, "not only does engineering make them less harmful, but it also makes them better at what we want them to do. You don't lose anything; it's all a gain."

More recently, Leroueil studied other types of charged nanoparticles called polycationic polymers---already being used to deliver drugs and genes---to see if they behaved like dendrimers. "It turns out that they cause the same permeability and, in general, they cause membrane destruction as well," said Banaszak Holl. Neutral polymers, however, did not damage membranes.

Both Leroueil's work and the earlier research used model membranes to probe the effects of nanoparticles. Now, the research group is exploring their interactions with living cells.

"Just because we see hole formation in the model system doesn't mean that it really happens in the cell," said Banaszak Holl. But early results of experiments with living cells suggest that the same types of nanoparticles that punch holes in model membranes also damage membranes in living cells and make the membranes more permeable. Hong is now trying to learn more about the biological mechanisms involved. The usual explanation for how polycationic polymers and similar nanoparticles get into cells involves a process called polycation-mediated endocytosis. But Hong's experiments suggest that nanoscale hole formation may be at least as important in allowing materials to travel through membranes.

The work that Banaszak Holl, Hong and Leroueil will discuss is one of several major research programs under way in the U-M Center for Biologic Nanotechnology---a multi-disciplinary group includes researchers from the Medical School, the College of Engineering, and the College of Literature, Science, and the Arts, and focuses on biomedical applications of nanomaterials. Collaborators on this work include James R. Baker, Jr., the Ruth Dow Doan Professor of Biologic Nanotechnology; Bradford Orr, professor of physics and director of the Applied Physics Program; research associate Jennifer Peters and research investigators Anna Bielinska and Istvan Majoros.


Source:University of Michigan

Related biology news :

1. Probing The Promise And Perils Of Nanoparticles
2. Priming embryonic stem cells to fulfill their promise
3. Polymers with copper show promise for implanted sensors
4. New drug shows promise as powerful anticancer agent
5. Test for early detection of prostate cancer shows promise
6. Confocal imaging promises early detection of skin cancer
7. Its electric: Cows show promise as powerplants
8. Unusual antibiotics show promise against deadly superbugs
9. Novel compounds show promise as safer, more potent insecticides
10. Compound from Chinese medicine shows promise in head and neck cancer
11. Discovery of T-cell traffic control boosts new drug promise
Post Your Comments:

(Date:11/17/2015)... LIVERMORE, Calif. , Nov. 17, 2015  Vigilant ... has joined its Board of Directors. ... Vigilant,s Board after recently retiring from the partnership at ... owning 107 companies with over $140 Billion in revenue.  ... performance improvement across all the TPG companies, from 1997 ...
(Date:11/12/2015)... -- A golden retriever that stayed healthy despite having the ... a new lead for treating this muscle-wasting disorder, report ... MIT and Harvard and the University of São Paolo ... Cell, pinpoints a protective gene that boosts muscle ... Boston Children,s lab of Lou Kunkel , PhD, ...
(Date:11/11/2015)... MedNet Solutions , an innovative SaaS-based eClinical technology company that ... announce that it will be a Sponsor of the ... held November 17-19 in Hamburg , Germany.  ... iMedNet , MedNet,s easy-to-use, proven and affordable eClinical ... able to deliver time and cost savings of up to ...
Breaking Biology News(10 mins):
(Date:11/24/2015)... Worcester, Mass. (PRWEB) , ... November 24, 2015 ... ... need to maintain healthy metabolism. But unless it is bound to proteins, copper ... Institutes of Health (NIH), researchers at Worcester Polytechnic Institute (WPI) will conduct a ...
(Date:11/24/2015)... RALEIGH, N.C. , Nov. 24, 2015  Clintrax Global, Inc., ... Raleigh, North Carolina , today announced that the company has ... earnings represented a 391% quarter on quarter growth posted for Q3 ... Kingdom and Mexico , with the ... place in December 2015. --> United Kingdom ...
(Date:11/24/2015)... Muncie, IN (PRWEB) , ... November 24, 2015 , ... ... its newest Special Interest Group (SIG), MultiGP, also known as Multirotor Grand Prix, to ... in the last few years. Many AMA members have embraced this type of racing ...
(Date:11/24/2015)... 24, 2015  Tikcro Technologies Ltd. (OTCQB: TIKRF) today announced that its ... at 11:00 a.m. Israel time, at the law ... Allon Street, 36 th Floor, Tel Aviv, Israel ... and Izhak Tamir to the Board of Directors; ... directors; , approval of an amendment to certain terms of options ...
Breaking Biology Technology: