They’ve been able to recover blood from the 5000 year old Iceman Mummy and answer a question regarding his (Ötzi’s) death according to the May 8, 2012 news item on Nanowerk,

His DNA has been decoded; samples from his stomach and intestines have allowed us to reconstruct his very last meal. The circumstances of his violent death appear to have been explained. However, what had, at least thus far, eluded the scientists, was identifying any traces of blood in Ötzi, the 5,000 year old glacier mummy. Examination of his aorta had yielded no results. Yet recently, a team of scientists from Italy and Germany, using nanotechnology, succeeded in locating red blood cells in Ötzi’s wounds, thereby discovering the oldest traces of blood to have been found anywhere in the world …

The research paper “Preservation of 5300 year old red blood cells in the Iceman” ([free access] Interface: Journal of the Royal Society) written by Marek Janko, Robert W. Stark, and Albert Zink helps outsiders like me better understand why there is excitement about finding blood, from the Introduction to the paper (footnotes have been edited out),

Examining mummies with sensitive analytic tools enables the reconstruction of their ancestry and genetic relationships, diet, diseases, living conditions, state of preservation and the mummification processes. While many studies provided molecular evidence for the presence of infectious diseases in ancient populations, leading to deep insights into the evolution of such diseases, only a few reports on the recovery of blood from mummified bodies are available. Previous investigations, based on optical or electron microscopy data, postulated that blood remains or fragments could be preserved in mummies as old as 2000 years. [emphases mine] Although molecular verification of blood findings was not performed, detection of blood components was of major interest because it could give new perspectives on the lives and fates of our ancestors. Blood can indicate the general health status of an individual and it can be analysed to detect pathological conditions or to provide valuable information in forensic crime scene investigations.

So finding blood in the 5000 year old Iceman Mummy means this sample is more than double the age of previous samples. It also answers a question about his death, from the May 8, 2012 news item on Nanowerk,

Whilst examining the wound at the point where the arrow entered the body, the team of scientists also identified fibrin, a protein involved in the clotting of blood. “Because fibrin is present in fresh wounds and then degrades, the theory that Ötzi died some days after he had been injured by the arrow, as had once been mooted, can no longer be upheld,” explains Albert Zink.

They used an atomic force microscope for part of this project,

The team of scientists used an atomic force microscope to investigate thin tissue sections from the wound where the arrow entered Ötzi’s back and from the laceration on his right hand. This nanotechnology instrument scans the surface of the tissue sections using a very fine probe. As the probe moves over the surface, sensors measure every tiny deflection of the probe, line by line and point by point, building up a three-dimensional image of the surface. What emerged was an image of red blood cells with the classic “doughnut shape”, exactly as we find them in healthy people today.

Here’s an image of the blood,

This finding, as exciting as it is from an historical perspective, also hints at possible future applications for modern forensic science, from the May 8, 2012 news item on Nanowerk,

“Up to now there had been uncertainty about how long blood could survive – let alone what human blood cells from the Chalcolithic period, the Copper Stone Age, might look like.” This is how Albert Zink, Head of the Institute for Mummies and the Iceman at the European Academy, Bozen-Bolzano (EURAC) explains the starting point for the investigations which he undertook with Marek Janko and Robert Stark, materials scientists at the Center of Smart Interfaces at Darmstadt Technical University.

Even in modern forensic medicine it has so far been almost impossible to determine how long a trace of blood had been present at a crime scene. Scientists Zink, Janko and Stark are convinced that the nanotechnological methods which they tested out on Ötzi’s blood to analyse the microstructure of blood cells and minute blood clots might possibly lead to a break-through in this area.

EURAC’s Institute for Mummies and the Iceman is rather interesting, from the Institute for Mummies and the Iceman webpage,

The EURAC-Institute for Mummies and the Iceman gathers and coordinates all currently available scientific data on the Iceman and various other mummies.
Founded in 2007, it also supplies new impulses for anthropological, palaeopathological, genetic and medical research. In addition, it promotes innovative techniques for mummy conservation.

The EURAC-Institute for Mummies and the Iceman strongly supports and promotes the use of non-and minimal invasive investigation methods, such as computer tomography, nanotechnology, molecular and biological approaches, as well as ancient DNA research.  It collaborates with several renowned universities and museums worldwide.

The creation of a mummy research centre in Bolzano was generally welcomed, in particular by those who were more or less directly involved with studies on the Iceman, not least because the EURAC-Institute for Mummies and the Iceman assures optimal conservation conditions for the mummy.

One of the EURAC-Institute for Mummies and the Iceman’s tasks is gathering all available scientific data on the Iceman. This includes archaeological site material, as well as papers, notes, documentation material from research groups from all over the world.

The Iceman was found in 1991 in the Alps and is the oldest wet mummy ever discovered (dated 3.300-3.150 BC). He spent seven years in Innsbruck (A) thereafter, where he was extensively studied at the Research Institute for Alpine Prehistory. Meanwhile, the South Tyrolean Museum of Archaeology was established in Bolzano and a specially designed refrigerating chamber was created in order to preserve this unique mummy. In 1998, once the mummy had been moved to Bolzano, the Research Institute for Alpine Prehistory in Innsbruck was closed and all studies concerning the Iceman were carried out at different Universities.

That excerpt from the Institute’s webpage was a bit off tangent but I do find the “specially designed refrigerating chamber” a rather intriguing detail.