Scientists investigate transport of nanoparticles in the human body

March 19, 2010
During the investigation polystyrene nanoparticles were injected into the mother’s blood supply. Scientists then observed whether these were able to pass into the baby's blood supply.

The question of whether or not nanoparticles have an effect on the human body - and if so, how - is still largely unanswered. There is little information, for instance, on whether pregnant women exposed to these minute particles pass them on to their unborn babies. Scientists from Empa and the University Hospital Zurich (Switzerland) now show first results.

Nanotechnology is not only expected to help overcome existing challenges in the realms of medicine, energy supply and environmental protection; it is also considered one of the motors of innovation for the Swiss economy. This new technology will, however, only be able to establish itself in the long run if potential risks associated with it - such as those posed by free - are fully investigated and understood.

Over several years, Empa researchers have been studying the effects of numerous nanoparticles on and tissue. These investigations will help scientists to understand what problems - if any - these tiny things might cause when released into the (and in the environment). In a study recently published in the journal “” scientists from Empa and the University Hospital Zurich have investigated a very special organ, the human placenta. It acts as a filter of sorts between a mother and her unborn child. Responsible for supplying the fetus with sufficient nutrients and oxygen, the placenta also ensures that the circulatory systems of mother and child do not mix. The researchers wanted to know if nanoparticles were able to cross the placental barrier.

Is it a tight barrier for nanoparticles?

Established animal models, such as those for mice and rats, cannot be used for this purpose as the placenta in these creatures is fundamentally different from that of humans. Normally it is not easy to carry out scientific investigations on placental tissue, but several mothers who gave birth to their babies in the hospital agreed to allow the researchers to use their placentas for this study. In the laboratory it is possible to maintain both the mother’s and the baby’s circulatory systems (which are closely linked) for several hours in these donated organs.

The investigation required the researchers to add fluorescent polystyrene nanoparticles to the mother’s blood circulation and then observe if they were able to pass into the fetal circulation. Polystyrene particles are particularly suitable for this kind of test as they do not cause stress in the surrounding tissue and are easily detected. The particles injected into the placenta were of different sizes, ranging from 50 nanometers up to half a micron (500 nanometers) in diameter. The first result of the study was that the cutoff size of the beads was between 200 and 300 nanometers. Particles smaller than this, crossed the placental barrier and entered the fetal circulation while larger particles were held back.

Learning to understand the transport mechanism

The fact that particles below a certain size are able to pass through to the placental tissue to the is not really unexpected, but the phenomenon must certainly be subject to further study, the investigators say. They are therefore keen to understand the mechanism, by which the particles are transported across the barrier - in both directions. They are not doing this purely for the love of research, though. They would like to determine how, in future, nanoparticles might be used for therapeutic purposes. The tiny particles could feasibly be employed as a vehicle to transport drugs in a targeted fashion to the circulatory system of an unborn child, without this affecting the mother’s health.

Explore further: Something in the air: Nanoparticles and ...?

More information:Barrier Capacity of Human Placenta for Nanosized Materials”, Peter Wick, Antoine Malek, Pius Manser, Danielle Meili, Xenia Maeder-Althaus, Liliane Diener, Pierre-André Diener, Andreas Zisch, Harald F. Krug, and Ursula von Mandach, Environmental Health Perspectives, Volume 118, Number 3, March 2010

Related Stories

Something in the air: Nanoparticles and ...?

July 26, 2006

The world's first machine to simultaneously measure two vital properties of airborne nanoparticle pollution is going on an overseas trip to a leading atmospheric chemistry laboratory in Switzerland.

New placenta screening for high-risk pregnancies

April 2, 2007

For the first time ever, a team of Toronto researchers are using a combination of ultrasound and blood tests to screen high-risk pregnant mothers for placental damage. By completing these non-invasive tests, most high-risk ...

Clues to ancestral origin of placenta emerge in Stanford study

April 14, 2008

Researchers at the Stanford University School of Medicine have uncovered the first clues about the ancient origins of a mother's intricate lifeline to her unborn baby, the placenta, which delivers oxygen and nutrients critical ...

Nanoparticles may cause DNA damage across a cellular barrier

November 5, 2009

( -- Scientists have shown in the laboratory that metal nanoparticles damaged the DNA in cells on the other side of a cellular barrier. The research, by the University of Bristol, is published online this week ...

Recommended for you

Physicists develop new technique to fathom 'smart' materials

November 26, 2015

Physicists from the FOM Foundation and Leiden University have found a way to better understand the properties of manmade 'smart' materials. Their method reveals how stacked layers in such a material work together to bring ...

Mathematicians identify limits to heat flow at the nanoscale

November 24, 2015

How much heat can two bodies exchange without touching? For over a century, scientists have been able to answer this question for virtually any pair of objects in the macroscopic world, from the rate at which a campfire can ...

New sensor sends electronic signal when estrogen is detected

November 24, 2015

Estrogen is a tiny molecule, but it can have big effects on humans and other animals. Estrogen is one of the main hormones that regulates the female reproductive system - it can be monitored to track human fertility and is ...


Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.