Nanotechnology Now







Heifer International

Wikipedia Affiliate Button


DHgate

Home > Press > Rice unveils ‘green' microcapsule production method

Abstract:
Mix-and-shake procedure leads to instant glass microbubbles

Rice unveils ‘green' microcapsule production method

Houston, TX | May 26, 2005

Chemical engineers from Rice University have developed a fundamentally new approach — the most environmentally sensitive yet devised — for making tiny hollow spheres called microcapsules. Microcapsule research is one of the most active fields in applied nanotechnology, with dozens of companies either developing or using the tiny containers – usually smaller than living cells – to deliver everything from drugs and imaging agents to perfumes and flavor enhancers.

In research appearing on the cover of this month's issue (Vol. 17, Issue. 9) of the journal Advanced Materials, Michael Wong and his research group describe an approach for making microcapsules that involves mixing a solution of polymer and salt with tiny particles of silica that contain just a few hundred atoms apiece.

Microcapsules are typically made by depositing layers of a coating onto a template or core, which has to be removed to form the hollow center of the structure. The core is usually burned out with high heat processes or dissolved with harsh chemicals. Both processes can damage both the microcapsules and their cargo.

“Our process takes place almost instantaneously, at room temperature, under normal pressure, in water, and at mild pH values,” said Wong, assistant professor of chemical and biomolecular engineering, and chemistry. “The spheres naturally become hollow during the self-assembly, which is highly unusual and is an advantage over existing methods.”

Wong's approach has advantages over other microcapsule production methods that involve spraying techniques. While these techniques can be scaled up, it is difficult to adjust the materials properties of the resulting microcapsules.

“We've shown that we can tailor the properties of our self-assembled microcapsules – make them smaller, larger, thicker or thinner – simply by changing the ingredients we start with or by adjusting the mixing procedure,” Wong said. “The underlying chemistry is so easy to perform that anyone who can pour, mix, and shake can make these microcapsules in less than a minute.”

Wong's process involves 'self-assembly,' meaning the hollow spheres form spontaneously when the nanoparticle building blocks are mixed with polymer and salt. Because the process takes place in water, any chemical or drug that's suspended in the water gets trapped inside the hollow sphere when it forms.

Besides encapsulating drugs, flavor compounds and other molecular cargo, Wong's team hopes to develop their microcapsules for drug delivery. They are already exploring ways — like using changes in pH or temperature — to trigger the microcapsules to open and release drugs. In addition, they've made magnetic microcapsules by using iron oxide nanoparticles instead of silica. This could allow doctors to use magnets to precisely position drugs prior to their release.

“We can also use fluorescent nanoparticles called quantum dots to make glowing hollow spheres, which could be useful for combined drug delivery and imaging,” Wong said.

Another potential application includes the delivery of medical imaging agents. For example, most contrast agents that doctors use to improve diagnoses from magnetic resonance imaging are highly toxic. If a small quantity can be sealed away in a microcapsule, safe from contact with any living cells, it could alleviate illness and side effects that patients experience today.

The microcapsules could also be used to encapsulate enzymes, complex biomolecules that that govern many cellular processes. Because enzymes are fragile and expensive, engineers would like to protect them during chemical reactions so they can be used many times over.

Wong's group has shown they can do that to by storing enzymes inside the microcapsules. Their data show that enzymes didn't leak through the walls of the microcapsules, but smaller molecules did, meaning the enzymes could still carry out their prime function and act as a catalyst for chemical reactions. Wong believes the technology could be used to make micro-bioreactors that could be used in large-scale chemical or drug production.

“In comparison with the other methods of making microcapsules, the scale-up for our process is simple and inexpensive,” said Wong. “We believe this gives us a very competitive advantage over competing processes, and a number of companies have expressed an interest in the process.”

Wong's research was funded by Halliburton Energy Services. Oak Ridge Associated Universities, Kraft Foods and Rice University.

####

About Rice:
Rice University is consistently ranked one of America's best teaching and research universities. It is distinguished by its: size - 2,850 undergraduates and 1,950 graduate students; selectivity -10 applicants for each place in the freshman class; resources‹an undergraduate student-to-faculty ratio of 6-to-1, and the fifth largest endowment per student among American universities; residential college system, which builds communities that are both close-knit and diverse; and collaborative culture, which crosses disciplines, integrates teaching and research, and intermingles undergraduate and graduate work. Rice's wooded campus is located in the nation's fourth largest city and on America's South Coast.

Contact:
Jade Boyd
(713) 348-6778
jadeboyd@rice.edu

Copyright © Rice University

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related News Press

Possible Futures

Nanotechnology in Medical Devices Market is expected to reach $8.5 Billion by 2019 March 25th, 2015

Nanotechnology Enabled Drug Delivery to Influence Future Diagnosis and Treatments of Diseases March 21st, 2015

Nanocomposites Market Growth, Industry Outlook To 2020 by Grand View Research, Inc. March 21st, 2015

Nanotechnology Drug Delivery Market in the US 2012-2016 : Latest Report Available by Radiant Insights, Inc March 16th, 2015

Self Assembly

Designer's toolkit for dynamic DNA nanomachines: Arm-waving nanorobot signals new flexibility in DNA origami March 27th, 2015

Four Scientists With Major Contributions to Research at Brookhaven Lab Named American Physical Society Fellows March 17th, 2015

Nanotubes self-organize and wiggle: Evolution of a nonequilibrium system demonstrates MEPP February 10th, 2015

Engineering self-assembling amyloid fibers January 26th, 2015

Nanomedicine

Novel nanoparticle therapy promotes wound healing March 27th, 2015

Graphene reduces wear of alumina ceramic March 26th, 2015

Application of Graphene Oxide in Body Implants in Iran March 26th, 2015

Nanorobotic agents open the blood-brain barrier, offering hope for new brain treatments March 25th, 2015

Announcements

Nanoscale worms provide new route to nano-necklace structures March 29th, 2015

Solving molybdenum disulfide's 'thin' problem: Research team increases material's light emission by twelve times March 29th, 2015

A first glimpse inside a macroscopic quantum state March 28th, 2015

DFG to Establish One Clinical Research Unit and Five Research Units: New Projects to Investigate Complications in Pregnancy, Particle Physics, Nanoparticles, Implants and Transport Planning / Approximately 13 Million Euros in Funding for an Initial Three-Year Period March 28th, 2015

Environment

Young NTU Singapore spin-off clinches S$4.3 million joint venture with Chinese commercial giant March 23rd, 2015

New processing technology converts packing peanuts to battery components March 22nd, 2015

EU Funded PCATDES Project has completed its half-period with success March 19th, 2015

Are current water treatment methods sufficient to remove harmful engineered nanoparticle? March 10th, 2015

NanoNews-Digest
The latest news from around the world, FREE




  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoTech-Transfer
University Technology Transfer & Patents
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More










ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project







© Copyright 1999-2015 7th Wave, Inc. All Rights Reserved PRIVACY POLICY :: CONTACT US :: STATS :: SITE MAP :: ADVERTISE