Navigation Links
Bristly spheres as capsules
Date:3/6/2009

This release is available in German.

Amphiphilic molecules, which have one water-friendly (hydrophilic) end and one water-repellant (hydrophobic) end, spontaneously aggregate in aqueous solutions to make superstructures like capsules or bilayers. This phenomenon is responsible for the effects of detergents and soaps. Dirt is enclosed in little capsules of surfactant, which makes it water-soluble. Cell membranes are also based on this principle: they are simply lipid bilayers, an aggregation of lipid molecules that line up with their hydrophobic tails all together and their hydrophilic heads protruding into the aqueous environment. As reported in the journal Angewandte Chemie, researchers at the Universities of Hamburg and Freiburg (Germany) led by Horst Weller and Stephan Frster have now produced amphiphilic hybrid particles made of a water-insoluble inorganic nanoparticle at the core surrounded by a bristle-like layer of hydrophilic polymer chains.

The inorganic nanoparticles are made of cadmium selenide and cadmium sulfide. Polyethylene oxide chains are attached to the nanoparticles through amino groups. The nature of the superstructures formed in aqueous solution depends on how densely the surfaces of the little spheres are covered with the polymer "bristles". If they are densely packed, the hybrid particles remain in solution as individuals, because the bristles repel each other. If the bristles are less dense, dimers and trimers are formed; still sparser bristles result in long wormlike aggregates of many particles that grow into a network through occasional Y-shaped branches. For the particles to aggregate in this way, the bristles on the surfaces of the inorganic cores have to reorganize significantly: they move aside a little to free up points of contact so the cores can attach to each other. Aggregation then continues until the resulting ensemble of cores is, as a whole, surrounded by a sufficiently dense layer of bristles, which acts as a shield toward additional particles.

Cores with an even smaller number of polymer bristles aggregate into extended curved layers that close themselves off into capsule-shaped vesicles. The walls of the vesicles consist of a monolayer of the bristly particles.

The polymer-coated spheres offer a new, simple method for the controlled production of superstructures. The vesicles could be used to encapsulate drugs, for example, as contrast agents, or as ordered liquid crystalline phases for the production of nanostructured hybrid materials.


'/>"/>

Contact: Stephan Foerster
forster@chemie.uni-hamburg.de
49-404-283-83460
Wiley-Blackwell
Source:Eurekalert  

Related biology technology :

1. First U.S. Implants of Newly Approved Embozene(TM) Color-Advanced Microspheres Embolization Platform
2. SoluLinK Introduces NanoLink(TM) Streptavidin Magnetic Microspheres
3. CeloNova BioSciences Announces Worlds First Line of Fully Color-Coded Embolic Particles at CIRSE: Embozene(TM) Color-Advanced Microspheres
4. FDA Approves KAPIDEX(TM) (Dexlansoprazole) delayed release capsules for the Treatment of GERD
5. China Pharma Holdings, Inc. Receives SFDA Production Approval for Tiopronin Enteric-Coated Capsules
6. Cephalon and Eurand Announce Notification of Generic Filing for Cyclobenzaprine Hydrochloride Extended-Release Capsules
7. NicOx Signs Agreement With Capsugel for the Commercial Manufacture of Naproxcinod Oral Capsules
8. Barr Receives Approval for Generic Version of Razadyne(R) ER Capsules
9. FDA Approves ALOXI(R) (Palonosetron HCl) Capsules for Prevention of Acute Chemotherapy-induced Nausea and Vomiting
10. Ranbaxy Launches Omeprazole 40 mg Capsules
11. Par Pharmaceutical Receives Final Approval to Market Generic Marinol(R) CIII (Dronabinol) Capsules
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
Bristly spheres as capsules
(Date:10/12/2017)... ... October 12, 2017 , ... ... genomics analysis platform specifically designed for life science researchers to analyze and ... researcher Rosalind Franklin, who made a major contribution to the discovery of ...
(Date:10/11/2017)... ... ... wash is a basic first aid supply for any work environment, but most personal eye ... first if a dangerous substance enters both eyes? It’s one less decision, and likely quicker ... eye piece. , “Whether its dirt and debris, or an acid or alkali, getting anything ...
(Date:10/11/2017)... INDIANAPOLIS , Oct. 11, 2017  VMS BioMarketing, a ... of a nationwide oncology Clinical Nurse Educator (CNE) network, which ... growing need for communication among health care professionals to enhance ... physicians, nurses, office staff, and other health care professionals to ... for breast cancer. ...
(Date:10/11/2017)... ... October 11, 2017 , ... ... and pregnancy rates in frozen and fresh in vitro fertilization (IVF) ... maternal age to IVF success. , After comparing the results from the fresh ...
Breaking Biology Technology:
(Date:10/4/2017)... Oct. 4, 2017  GCE Solutions, a global clinical research organization ... document anonymization solution on October 4, 2017. Shadow is designed to ... comply with policy 0070 of the European Medicines Agency (EMA) in ... ... ...
(Date:6/30/2017)... , June 30, 2017 Today, ... developer and supplier of face and eye tracking ... Featured Product provider program. "Artificial ... innovative way to monitor a driver,s attentiveness levels ... from being able to detect fatigue and prevent ...
(Date:5/16/2017)... May 16, 2017  Veratad Technologies, LLC ( www.veratad.com ... age and identity verification solutions, announced today they will ... 2017, May 15 thru May 17, 2017, in ... International Trade Center. Identity impacts the ... in today,s quickly evolving digital world, defining identity is ...
Breaking Biology News(10 mins):