The nanogels — only 200 nanometers in diameter — possess many unique properties that make them ideal drug-delivery tools, according to Daniel Siegwart, a graduate student in University Professor Krzysztof Matyjaszewski’s laboratory at Carnegie Mellon. Siegwart will present his research Monday, Aug. 20 at the 234th national meeting of the American Chemical Society in Boston.
ATRP, a controlled living radical polymerization process, allows chemists to precisely regulate the composition and architecture of the polymers they are creating. Siegwart and colleagues used ATRP in inverse miniemulsion to make nanogels with a uniform network of cross-linked polymer chains within a spherical nanoparticle.
“A uniform mesh size within the nanogels should improve the controlled release of the encapsulated drugs,” said Siegwart. “The major advance of this system is that ATRP allows one to prepare nanogels that are uniform in diameter. The size of the particles can be tuned, and we are currently investigating how nanogels of different sizes enter cells. The results may allow us to better understand the mechanism of endocytosis and to target specific tissues, such as cancer cells that have a more permeable membrane.”
In their most recent advance, the Carnegie Mellon team incorporated the model carbohydrate drug rhodamine isothiocyanate-labeled dextran into the nanogel’s uniform mesh core. When the nanogels degraded, the model carbohydrate drug was released over time. The experiments were carried out with Jung Kwon Oh, a former postdoctoral associate in the Matyjaszewski lab who developed ATRP in inverse miniemulsion.
The new nanogels, which are nontoxic and biodegradable, can also accommodate molecules on their surfaces. During nanogel synthesis, the ATRP process allows scientists to incorporate “targeting groups” on the nanogel surface that can interact with specific receptors, such as those on the surface of a cancer cell. In addition, the nanogels can escape the notice of the body’s immune system, thus prolonging circulation time within the bloodstream.
“The basic composition of the nanogels is based on an analogue of poly(ethylene oxide), a well-established biocompatible polymer that can enhance blood circulation time and prevent clearance by the reticuloendothelial system, the part of the immune system that engulfs and removes foreign objects from the body,” said Siegwart.
In a recent article published in the Journal of the American Chemical Society, the Carnegie Mellon team demonstrated that its novel nanogels could be used to encapsulate doxorubicin, an anticancer drug. When the scientists mixed the doxorubicin-loaded nanogels with HeLa cancer cells in the laboratory, the doxorubicin was released, penetrating the cancer cells and significantly inhibiting their growth. They carried out this work in collaboration with Jeffrey Hollinger, professor of biomedical engineering and biological sciences and director of the Bone Tissue Engineering Center at Carnegie Mellon.
Flavins keep a handy helper in their pocket
25.04.2018 | University of Freiburg
Complete skin regeneration system of fish unraveled
24.04.2018 | Tokyo Institute of Technology
At the Hannover Messe 2018, the Bundesanstalt für Materialforschung und-prüfung (BAM) will show how, in the future, astronauts could produce their own tools or spare parts in zero gravity using 3D printing. This will reduce, weight and transport costs for space missions. Visitors can experience the innovative additive manufacturing process live at the fair.
Powder-based additive manufacturing in zero gravity is the name of the project in which a component is produced by applying metallic powder layers and then...
Physicists at the Laboratory for Attosecond Physics, which is jointly run by Ludwig-Maximilians-Universität and the Max Planck Institute of Quantum Optics, have developed a high-power laser system that generates ultrashort pulses of light covering a large share of the mid-infrared spectrum. The researchers envisage a wide range of applications for the technology – in the early diagnosis of cancer, for instance.
Molecules are the building blocks of life. Like all other organisms, we are made of them. They control our biorhythm, and they can also reflect our state of...
University of Connecticut researchers have created a biodegradable composite made of silk fibers that can be used to repair broken load-bearing bones without the complications sometimes presented by other materials.
Repairing major load-bearing bones such as those in the leg can be a long and uncomfortable process.
Study published in the journal ACS Applied Materials & Interfaces is the outcome of an international effort that included teams from Dresden and Berlin in Germany, and the US.
Scientists at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) together with colleagues from the Helmholtz-Zentrum Berlin (HZB) and the University of Virginia...
Novel highly efficient and brilliant gamma-ray source: Based on model calculations, physicists of the Max PIanck Institute for Nuclear Physics in Heidelberg propose a novel method for an efficient high-brilliance gamma-ray source. A giant collimated gamma-ray pulse is generated from the interaction of a dense ultra-relativistic electron beam with a thin solid conductor. Energetic gamma-rays are copiously produced as the electron beam splits into filaments while propagating across the conductor. The resulting gamma-ray energy and flux enable novel experiments in nuclear and fundamental physics.
The typical wavelength of light interacting with an object of the microcosm scales with the size of this object. For atoms, this ranges from visible light to...
13.04.2018 | Event News
12.04.2018 | Event News
09.04.2018 | Event News
25.04.2018 | Physics and Astronomy
25.04.2018 | Physics and Astronomy
25.04.2018 | Information Technology