Sperm cells are basically motorized packets of DNA. Once their fuse is lit, they burn full bore like a solid fuel bottle rocket until they reach their target. If used as directed, they eventually meet up with an egg for a quick round of Castle Seige, then expire like salmon after a spawn. Researchers from the Dresden Institute for Integrative Nanosciences, a stronghold of Germany ingenuity, realized that if these minions could be trained, or rather, entrained, they might be harnessed to creative end.
The Dresden researchers came up with something they call a spermbot. It is really more of a sperm boat, made from tapered tubes of iron and titanium. Since sperm deploy just a single flagellum, and don’t have a reverse gear, if they don one of these tubes, they wear it for life. The researchers can then control the exact heading of the sperm by manipulating external magnetic fields which tug at the iron nanoparticles embedded in the tube. They can also increase the speed of the sperm by increasing the temperature. In principle local temperature control through focused laser might even allow individual sperm to be directly selected for a higher purpose.
Applications for this new technology are developing at a furious pace. Those who thoughtin vitro fertilization was cool can’t wait to try their hand at in vivo magnetically-enhanced insemination. Targeted drug delivery may also be possible using specialized sperm shuttles. Even non-biologic tools based on sperm propulsion could built to act as microassemblers. There is also just the sheer entertainment value of robotsperm for use in next generation battlebots.
Some of the more precision capabilities of sperm came to light recently with the claims that mice can pass on an acquired fear of specific events through some unknown agent in their sperm. The question remains as to how all this programming is actually done. With an experimental platform like the Dresden spermbot gymnasium, not only might sperm reveal some of their secrets through their behaviors, but those skills might actually be selected for, or even influenced.
Before any such hunger games come to be, the question of what these manipulations might do to the natural course of healthful events in fertilization needs to be asked. However, astride current accepted in vitro techniques, where frozen worn out sperm, or triplex-parented eggs with full mitochondrial transplants are now par for the course, spermbots should not seem all that dramatic. The field has come a long way since the great Leewenhoek crafted his microscope and stole the first glimpse of nature’s flagellated emissaries, yet much still remains to be discovered.