Engineers Combat Infertility with Motorized Spermbots

Helical motors help with low sperm motility.

(Image courtesy of American Chemical Society.)

(Image courtesy of American Chemical Society.)

A team of scientists and engineers has developed motorized “spermbots” to deliver otherwise healthy poor swimmers to the ovum.

Building on previous research on microscopic motors, the researchers constructed tiny metal helices just large enough to fit around the tail of a sperm. The movement of these helices can be controlled using a rotating magnetic field.

Laboratory testing showed that the motors can be directed to slip around a sperm cell. With the motor attached, the cell can be driven to an egg for potential fertilization.

Check out the video below to see the spermbots in action:

Engineering a Solution to Infertility

Low sperm motility is one of the leading causes of infertility.

The typical medical response to this problem is to turn to artificial insemination or in-vitro fertilization. The former is simple and relatively inexpensive. It involves introducing sperm into the uterus with a medical instrument.

However, according to the Human Fertilisation & Embryology Authority of the United Kingdom the average success rate for artificial insemination is under 30 percent.

In-vitro fertilization is more effective, but it’s also more complicated and expensive since it requires actually removing eggs from the ovaries with a needle. The eggs are then fertilized outside the body and the resulting embryos are transferred to a uterus a few days later.

Bioengineer Mariana Medina-Sanchez and her colleagues at the Institute for Integrative Nanosciences at IFW Dresden wanted to find a better solution. Although much more work is needed before their spermbots reach the clinical testing phase, the success of the research team’s initial demonstration is an encouraging start.

A spermbot delivering a slow swimmer to an ovum. (Image courtesy of American Chemical Society.)

A spermbot delivering a slow swimmer to an ovum. (Image courtesy of American Chemical Society.)

It’s not hard to imagine a possible final outcome: rather than women having undergo artificial insemination or in-vitro fertilization procedures, men could be given a simple injection of metal helices in saline. Rotating magnetic fields could then direct the helices to the appropriate anatomical location and have them link up with low motility sperm cells.

The lingering question is how the spermbots would be directed toward the ovum, unless the researchers plan to have rotating magnetic fields in the bedroom.

The research is published as a report in the American Chemical Society journal, Nano Letters.

Written by

Ian Wright

Ian is a senior editor at engineering.com, covering additive manufacturing and 3D printing, artificial intelligence, and advanced manufacturing. Ian holds bachelors and masters degrees in philosophy from McMaster University and spent six years pursuing a doctoral degree at York University before withdrawing in good standing.