Per Olaf Ekstrøm

  • Senior scientist; Dr. philos.
  • +47 2278 1847


I was introduced to research in 1991 when I start working at The Norwegian Radium hospital (DNR) as a research technician. Parallel to this work I was able to complete my Ph.D. with the title “The use of microdialysis to investigate extracellular pharmacokinetics of methotrexate” in 1997. This was followed by a 2-year post doc period at MIT. Here I work with separating DNA by capillary electrophoresis and thouched upon US cancer mortality curves as shown on Prof. Thillys web page.  In 1999 I returned to DNR and continued the development of DNA separation in multi capillary instruments. This lead to the first publication on the method of separation of DNA by cycling temperature capillary electrophoresis (December 2002, (PMID: 14599347)). Optimized and explored the separation principles of cycling temperature capillary electrophoresis which resulted in more than a dozen publications (PMID: 18600220, 22539319). Given the intimate knowledge of the method and the instrumentation, I can be regarded as an expert in this field. In the course of my research career I have embraced methods, methods development and technical skill on chemistry, troubleshooting and instrument maintains. Four Ph.D students have graduated under my supervision and used cycling temperature capillary electrophoresis (CTCE) as their main analysis method.

Below is an illustartion of separation by CTCE of two DNA molecules with the same length and one base pair difference. The separation takes place during one temperature cycle, in a capillary filled with an appropriate sieving matrix while the DNA migrates in an electric field (electrophoresis). The more cycles applied the better separation between the DNA variants.

Effect of cycling temperature on DNA

Color change indicate temperature change (blue-cold, red=warmer)

Velocity (v) of DNA is dependent on the entanglemet with the sieving matrix during electrophoresis.





Distribution of mitochondrial mutant fractions within tumors.

Instrumentation, Cycling temperature capillary electrophoresis (CTCE).

MegaBACE 1000 resource page

Distribution of somatic mutant fractions within a mouse tumor model.


Testing of in-house chemistry for Sars-Cov-2 analysis.

Real-time PCR


For information

Mitocohndrial research, the struckture usally depicted as a bean but it is NOT.

A cell was videoed through a confocal scanning microscope. DNA in the nucleus (blue), the powerhouses/overlords of the cell, mitochondria (yellow), and actin filaments (purple) are shown.

Different video, from @MAG2ART

Quantification of mitochondrial copy numbers with in-house chemistry

Data and recipe

(Work in progress)


Us of mitochondrial DNA variants as marker for clonality

(Work in progress)








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