The nanoparticles, which are capable of delivering and exchanging complementary molecules, emit a fluorescent signal that can be observed with a microscope.
Complementarity in molecular biology involves bringing together pairs of molecules that are mirror opposites of each other that yet fit together perfectly. Think of matching nucleotides within DNA strands. Besides transcribing and repairing genetic information, complementary molecules can be used to deliver bursts of energy by snapping the molecule pairs together. Researchers from University of Miami have developed special self-assembling nanoparticles for carrying and depositing complementary particles into living cells.
The nanoparticles are made of amphiphilic polymers and are hydrophobic on the inside to help contain the cargo, while being hydrophilic on the outside for safe travel through the body. Being only 15 nanometers in diameter, the nanoparticles are small enough to penetrate through cellular membranes. The researchers believe that this technology has wide implications in medicine, including for the delivery and precise activation of drugs only within the interior of cells.
More details from University of Miami:
Essential to this mechanism are the noncovalent bonds that loosely hold the supramolecular constructs together. These weak bonds exist between molecules with complementary shapes and electronic properties. They are responsible for the ability of supramolecules to assemble spontaneously in liquid environments. Under the right conditions, the reversibility of these weak noncovalent contacts allows the supramolecular constructs to exchange their components as well as their cargo.
The experiments were conducted with cell cultures. It is not yet known if the nanoparticles can actually travel through the bloodstream.
The next phase of this investigation involves demonstrating that this method can be used to do chemical reactions inside cells, instead of energy transfers.
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