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Human Cells Naturally 'Eat' Silicon Nanowires (ieee.org)
the_newsbeagle writes: By showing that human cells naturally engulf minuscule silicon nanowires, a material scientist from the University of Chicago has opened the way to intracellular electronics. Applications could include very specialized drug delivery, electrically stimulating the organelles inside the cell, or recording the signals that pass between those internal structures. From IEEE Spectrum: "Using both an electron microscope and a specialized optical imaging tool designed by the team, the group recorded the eating of the nanowires in detail. It appears that the cell's outer membrane folds itself like a pocket, grabs the nanowire, and envelops it in a membrane-lined bubble. The process is called phagocytosis; it's the same method used by immune cells to grab a bit of bacteria and swallow it up. Once the nanowire is inside, the cell's machinery then shuttles it through its system with sudden bursts of speed -- up to 99.4 nanometers per second -- and deposits it just outside the cell's nucleus. Tian's group made a video of the process (complete with melodramatic accompaniment)."
They swallow them, but they don't break them down, which means that when the cell dies (which it will), the material goes on a second journey and so on.
Religion is what happens when nature strikes and groupthink goes wrong.
I seem to once remember hearing another example of nanostructures finding their way into cells easily, and it didn't go well for the cell, in the longer run. I certainly hope they're doing extended life testing with this.
Most nano-particles don't transfect into cells (go actively into the cytoplasm itself). Generally, if there is cellular uptake, the nano-particles end up "in jail," trapped inside endosomes, and not actively in the cell's guts proper.
There are some materials that make for nice, rounded and non-cytotoxic nano-particles that can be functionalized and transfected into the cytoplasm. Such materials are the "Holy Grails" of drug delivery, cancer treatment, and diagnostics. I work on one of them...