Nanotechnology Now

Our NanoNews Digest Sponsors



Heifer International

Wikipedia Affiliate Button


android tablet pc

Home > Press > Small and efficient - water nanodroplets cool biomolecules ultrafast

Upper left: Schematic of a reverse micelle consisting of phospholipid molecules. The phosphate groups of the lipid molecules (blue spheres) are arranged at the inner surface of the micelle. Water molecules are located in the inner part of the micelle. Upper right: Enlarged view of the structure of a phospholipid molecule. Oxygen atoms are shown in red, hydrogen atoms in white, carbon atoms in grey, the nitrogen atom in blue, and the phosphorus atom in orange. The angled water molecules are arranged around the phosphate (PO4) group. Lower part: Scheme of energy transfer. In the experiments, the (asymmetric) phosphate vibration is initially excited (red oxygen atoms). The energy released in the decay of the vibration is transferred to the surrounding water shell (red H2O molecules) within 1 ps.
Upper left: Schematic of a reverse micelle consisting of phospholipid molecules. The phosphate groups of the lipid molecules (blue spheres) are arranged at the inner surface of the micelle. Water molecules are located in the inner part of the micelle. Upper right: Enlarged view of the structure of a phospholipid molecule. Oxygen atoms are shown in red, hydrogen atoms in white, carbon atoms in grey, the nitrogen atom in blue, and the phosphorus atom in orange. The angled water molecules are arranged around the phosphate (PO4) group. Lower part: Scheme of energy transfer. In the experiments, the (asymmetric) phosphate vibration is initially excited (red oxygen atoms). The energy released in the decay of the vibration is transferred to the surrounding water shell (red H2O molecules) within 1 ps.

Abstract:
Researchers of the Max-Born-Institute at Berlin, Germany, have observed how biomolecules transfer energy into extremely small water droplets in their environment. A water shell consisting of only 3 water molecules around a phospholipid molecule is sufficient for energy transfer within 1 ps.

Small and efficient - water nanodroplets cool biomolecules ultrafast

Berlin, Germany | Posted on December 2nd, 2012

Biochemical processes occur mainly in an aqueous environment. Particular groups of a biomolecule are embedded in a shell of water molecules, a process called hydration. The water shell stabilizes the biomolecular structure and enables an exchange of energy between the biomolecule and its environment. Examples are the double helix of DNA, the carrier of basic genetic information, in an aqueous medium and the membranes of living cells which consist of phospholipids. The molecular mechanisms, the speed and the efficiency of energy exchange between the biomolecule and the water shell are understood only in part and, thus, a topic of current basic research.

Scientists of the Max-Born-Institute have shown that extremely small water droplets embedding a phospholipid molecule enable efficient energy transfer on a time scale of 1 ps (1 ps = 10-12 s = 1 millionth of a millionth of a second). René Costard, Christian Greve, Ismael Heisler, and Thomas Elsaesser report in the current issue of Journal of Physical Chemistry Letters (vol.3, page 3646, 2012) that 3 water molecules around the phosphate group of the phospholipid are sufficient for transferring the energy of vibrations from the phospholipid into this minimal water shell. The transferred energy heats the water shell by 10 to 20 centigrades. The thermal energy is stored in tilting motions of water molecules, so called librations, and leads to a weakening of the interaction between the water molecules, the so called hydrogen bonds. The overall molecular structure of the water shell remains practically unchanged. This extremely efficient mechanism of energy disposal allows for the transfer of even larger amounts of energy, protecting the biomolecule against damage by overheating.

The researchers studied a phospholipid model system consisting of the DOPC molecules shown in Fig. 1. The molecules are arranged in so-called reverse micelles which contain the water molecules hydrating the phosphate groups. In this geometry, the hydration level, i.e., water content, can be changed in a wide range. For studying energy transfer, either phosphate vibrations of the phospholipid or OH stretching vibrations of water are excited by an infrared pulse of a 0.1 ps duration. The vibrations decay within a fraction of a picosecond and the energy released in this decay is transferred into the water shell. The transfer and redistribution of energy is mapped via transient two-dimensional infrared spectra of the OH stretching vibration of water. The weakening of hydrogen bonds in the heated water shell leads to a shift of the OH stretching spectra to higher frequencies. Measuring the change of the two-dimensional spectra as a function of time provides direct insight into the energy transfer dynamics.

Full bibliographic informationR. Costard, C. Greve, I. A. Heisler, T. Elsaesser: Ultrafast energy redistribution in local hydration shells of phospholipids: a two-dimensional infrared study. J. Phys. Chem. Lett. 3, 3646 (2012).

####

For more information, please click here

Contacts:
Thomas Elsaesser

Copyright © AlphaGalileo

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

News and information

Iranian Researchers Synthesize Stable Ceramic Nanopowders at Room Temperature September 20th, 2014

Arrowhead to Present at BioCentury's NewsMakers in the Biotech Industry Conference September 19th, 2014

SouthWest NanoTechnologies (SWeNT) Receives NIST Small Business Innovation Research (SBIR) Phase 1 Award to Produce Greater than 99% Semiconducting Single-Wall Carbon Nanotubes September 19th, 2014

Toward optical chips: A promising light source for optoelectronic chips can be tuned to different frequencies September 19th, 2014

New research points to graphene as a flexible, low-cost touchscreen solution September 19th, 2014

Physics

Toward optical chips: A promising light source for optoelectronic chips can be tuned to different frequencies September 19th, 2014

Elusive Quantum Transformations Found Near Absolute Zero: Brookhaven Lab and Stony Brook University researchers measured the quantum fluctuations behind a novel magnetic material's ultra-cold ferromagnetic phase transition September 15th, 2014

Discoveries

Iranian Scientists Separate Zinc Ion at Low Concentrations September 20th, 2014

Iranian Researchers Synthesize Stable Ceramic Nanopowders at Room Temperature September 20th, 2014

Toward optical chips: A promising light source for optoelectronic chips can be tuned to different frequencies September 19th, 2014

New research points to graphene as a flexible, low-cost touchscreen solution September 19th, 2014

Announcements

Iranian Scientists Separate Zinc Ion at Low Concentrations September 20th, 2014

Arrowhead to Present at BioCentury's NewsMakers in the Biotech Industry Conference September 19th, 2014

SouthWest NanoTechnologies (SWeNT) Receives NIST Small Business Innovation Research (SBIR) Phase 1 Award to Produce Greater than 99% Semiconducting Single-Wall Carbon Nanotubes September 19th, 2014

Toward optical chips: A promising light source for optoelectronic chips can be tuned to different frequencies September 19th, 2014

Water

Malvern Instruments & Aurora Water conference presentation illustrates value and cost-saving potential of on-line zeta potential in water treatment: 2014 RMSAWWA/RMWEA Joint Annual Conference, Albuquerque, New Mexico, USA September 7th – 10th September 3rd, 2014

New Nanosorbent Helps Elimination of Colorants from Textile Wastewater August 25th, 2014

Eco-friendly 'pre-fab nanoparticles' could revolutionize nano manufacturing: UMass Amherst team invents a way to create versatile, water-soluble nano-modules August 13th, 2014

PerkinElmer to Display Innovative Detection and Informatics Offerings at ACS National Meeting & Exposition Detection, Data Visualization and Analytics for Chemistry Professionals August 8th, 2014

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 1999-2014 7th Wave, Inc. All Rights Reserved PRIVACY POLICY :: CONTACT US :: STATS :: SITE MAP :: ADVERTISE