Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Hard Shell, Soft Core

25.06.2008
Enzyme used as nanoreactor for semiconductor synthesis at room temperature

Semiconductors have become indispensable for modern technology. For example, oxide semiconductors such as zinc oxide (ZnO) are the materials of choice for transparent conducting layers for blue LEDs, liquid crystal displays, and solar cells.

The large-scale production of such oxide semiconductors is an energy-intensive process. In order to decrease the energy expenditure, the search is on for new production processes that work under mild conditions. Researchers at the City University of New York's Hunter College have now developed a new approach that delivers zinc oxide at room temperature.

Hiroshi Matsui and Roberto de la Rica report in the journal Angewandte Chemie that they use the enzyme urease as a “nanoreactor” for the production of crystalline zinc oxide.

... more about:
»Oxide »Semiconductor »enzyme »urease »zinc

Urease is found in plant seeds, bacteria, and various sea creatures. It splits urea into carbon dioxide and ammonia. Ammonia is an alkaline substance; when urease is active, the pH value on the surface of the enzyme rises.

Because of the negative charge on its surface, urease has a high affinity for positively charged metal ions. In a zinc nitrate solution, the zinc ions aggregate around the urease. The local pH value on the surface of the enzyme can be finely tuned to values ideal for the formation of zinc oxide. The increasing zinc ion concentration at a suitable pH value catalyzes the formation and growth of ZnO crystals. The enzyme cores thus become surrounded by nanoshells of zinc oxide. These have a diameter of about 18 nm. By using slightly modified urease molecules, the size of the zinc oxide shells can be varied.

Author: Hiroshi Matsui, Hunter College, City University of New York (USA), http://www.hunter.cuny.edu/chem/faculty_files/matsui/matsui.html

Title: Urease as a Nanoreactor for Growing Crystalline ZnO Nanoshells at Room Temperature

Angewandte Chemie International Edition 2008, 47, No. 29, 5415–5417, doi: 10.1002/anie.200801181

Hiroshi Matsui | Angewandte Chemie
Further information:
http://pressroom.angewandte.org
http://www.hunter.cuny.edu/chem/faculty_files/matsui/matsui.html

Further reports about: Oxide Semiconductor enzyme urease zinc

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 >>>