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Tiny sponges trap toxins in the body

A California team of scientists has developed a nano sponge that disguises itself as a red blood cell. The tiny sponge is only 85 billionths of a meter tall and acts as bait in the bloodstream for poisons from animals or bacteria that can be dangerous to the organism. In an experiment on mice, almost 90 percent of the animals survived an actually lethal dose of poison.

US engineers have developed a plastic nano-sponge that is injected into the bloodstream, where it soaks up with toxins. The sponges are excreted through the liver.

Photo: University of San Diego / Screenshot: ingenieur.de

The engineers working with Liangfang Zhang from the University of San Diego constructed the nano sponge as a kind of universal antiserum. The tiny ball is in the bloodstream as bait for all kinds of pore-forming toxins. These toxins, which perforate and destroy the cell walls, are found in bee and snake poison, for example. They are also released by some bacteria. Certain strains of these germs such as MSRA (methicillin-resistant Staphylococcus aureus) are now resistant to almost all antibiotics.

Parts of red blood cells camouflage the nanosponges

The core of the small sponge is made of a plastic that the body can break down. As a camouflage, the researchers covered the tiny globule with components of the cell envelope of red blood cells. Thousands of nanosponges can be covered with the material of a single cell envelope. Each nanosponge is now 3,000 times smaller than a red blood cell.

A research team from the University of San Diego, consisting of (from left) Brian Luk, Che-Ming Jack Hu, Ronnie Fang, Jonathan Copp and Liangfang Zhang developed the nano-sponges that can flush toxins from the blood.

Source: University of San Diego

If the globules are injected into the bloodstream, the body's own immune system does not develop a defense against the intruder, because his camouflage makes him unsuspecting. The nanosponges flood the bloodstream and are quickly detected by alpha-hemolysin, the toxic substance of the MSRA staphylococci, which attacks the coats of red blood cells. The alpha hemolysin reacts as usual, digs into the shell of the nano sponges and is stored inside. About 40 hours later, half of the nano sponges have already disappeared again. The liver has broken down the artificial globules and their poisonous contents.

89 percent of the mice survived the lethal dose

In an experiment on mice that had recently been injected with nanosponges, 89 percent of the mice survived an otherwise fatal dose of alpha-hemolysin. If the infusion was given after the poison was already in the body, 44 percent survived. In the experiments, a nanosponge was able to absorb around 85 alpha-hemolysin substances. For bee venom, the ratio was around 850 toxins per nanosponge.

A major advantage of their method is that it can neutralize a wide range of toxins, the Californian scientists report. So far, a special treatment has to be developed for each individual toxin. In the next step, the researchers want to start clinical studies.

A contribution from:

  • Gudrun von Schoenebeck

    Gudrun von Schoenebeck has been a journalist in print and online media since 2001. In addition to architecture, art and design, she has above all opened up the exciting field of space travel.