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S C HW E R P U N K T 24 Further information: www.pharmazie.uni-jena.de/Abteilungen/ Pharmazeutische Technologie/Prof_ Dr_ Dagmar Fischer/Forschung Contact Prof. Dr Dagmar Fischer Institute of Pharmacy Lessingstr. 8, D-07743 Jena, Germany Phone: +49 36 41 9-49901 Email: dagmar.fischer@uni-jena.de www.pharmazie.uni-jena.de A method developed in Jena is used to test whether particles are toxic The Jena scientists developed this refi- nement to the research method them- selves. They can now observe the ef- fects on the egg and draw conclusions about what would happen if the par- ticles met human mucous membranes, for example in the mouth or eyes. »If the nanoparticles are toxic, they can destroy the surface«, explains Rabel. »Or they penetrate the bloodstream and stop it.« Furthermore, various pro- cesses could cause the blood or tissue to clot, which would cause a thrombo- sis or embolism. The diversity of the nanoparticles means that the range of reactions is vast. As part of one project, the pharmacists tested a variety of iron oxide particles and their polymers, which can serve as a coating. The team working with Prof. Dagmar Fischer has already spent ten years studying nanoparticles. Ten to twelve members of staff are currently wor- king on egg experiments. »We believe it is very important that all early-career scientists working within our field carry out the experiments themselves, so that they can learn and understand the method«, says Dagmar Fischer. In addition to the work on their own research, for example within the fra- mework of the »PolyTarget« collabo- rative research centre, they are also carrying out tests for other disciplines, such as material sciences or photonics, and for other research facilities as well as for private companies. Experiments using the chicken egg model help to reduce animal testing This has led to the creation of an ex- tensive database of information about nanoparticles. Despite the many im- portant insights that can be gained from the chicken egg models, scien- tists will still need to use animal tes- ting in the final stages to find out how the various nanoparticles affect the human body. But, thanks to the egg experiments, the number of these ex- periments required will be significant- ly less. »We clarify many properties of the particles in advance«, says Martin Rabel. »This speeds up the research and makes it more cost-effective.« It also highlights the ethically respon- sible approach, which is omnipresent with the work with the eggs. The diligence shown in the laboratory is clear, despite the routine. They work quietly and deliberately. Each move must be accurate—so no more eggs than necessary are used. Paul Warncke has already once again started filling a stack of petri dishes with the trans- parent nutrient solution, which feeds the egg and prevents it from drying out whilst in the solution. The docto- ral students will open a few hundred eggs today alone. »One thing’s for sure, I don’t eat eggs at home on days like this«, says Martin Rabel.  A great deal of sensitivity and a steady hand required: using a ring with a diameter of just a few millimetres, the pharmacists create a tiny pool on the egg yolk in which they can test the toxicity of nanoparticles.