Proteins are an interesting class of drugs because they demonstrate high biological activity and are highly specific in their effects. It has become possible to produce more and more proteins with tailored pharmacological properties; however transport and controlled release of the protein drugs in the body have remained a challenge.
In the journal Angewandte Chemie, Helmuth Möhwald of the Max Planck Institute of Colloids and Interfaces in Golm/Potsdam (Germany) and Dmitry V. Volodkin and Regine von Klitzing of the TU Berlin (Germany) have now introduced an alternative to the usual transport agents, such as liposomes: by using a simple, inexpensive, gentle process, they were able to produce pure protein microspheres of uniform size.
Loading nano- and microscale transport systems with proteins is the most common strategy used to bring drugs to their target area and achieve a longer period of activity. The challenge is to produce particles with a precisely defined quantity of protein, size, morphology, composition, and density. These characteristics are critical for the attainment of high bioavailability and a defined rate of release at the desired location. Unfortunately, they are difficult to control when using conventional methods for the production of protein particles, such as crystallization, spray drying, or incorporation in liposomes or polymer matrices. Another disadvantage is that these processes generally require organic solvents, high temperatures, or other conditions that can compromise the stability of the proteins.
The researchers were looking for a method that would deliver uniform protein particles without destructive additives and under mild conditions. The team has now developed such a method, which is also very simple and inexpensive, and successfully tested it on insulin, a classic therapeutic protein. The secret to their success lies in porous calcium carbonate microspheres of defined size, and a change of pH value. In a slightly alkaline aqueous environment (high pH value), the protein insulin is soluble. When the calcium carbonate spheres are added to such a protein solution, their pores are filled with the insulin solution. When the solution is then neutralized with acid, the insulin becomes insoluble and precipitates out in the pores. If the solution is acidified further, until the calcium carbonate spheres slowly begin to dissolve in the slightly acidic solution. The insulin remains behind as a loose matrix, which shrinks down into compact micrometer-scale spheres. This results in protein particles of uniform size and high protein density.
Author: Dmitry V. Volodkin, Technische Universität Berlin (Germany), http://www.chemie.tu-berlin.de/klitzing/menue/ueber_uns/arbeitsgruppe/volodkin/
Title: Pure Protein Microspheres by Calcium Carbonate Templating
Angewandte Chemie International Edition, Permalink to the article: http://dx.doi.org/10.1002/anie.201005089
Dmitry V. Volodkin | Angewandte Chemie
Pollen taxi for bacteria
18.07.2018 | Technische Universität München
Biological signalling processes in intelligent materials
18.07.2018 | Albert-Ludwigs-Universität Freiburg im Breisgau
For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.
To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...
For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.
Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...
Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.
A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...
Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.
"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....
Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.
Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...
13.07.2018 | Event News
12.07.2018 | Event News
03.07.2018 | Event News
18.07.2018 | Life Sciences
18.07.2018 | Life Sciences
18.07.2018 | Information Technology