Research Group

Magnetic Resonance by Optics

Group leader: Kirstine Berg-Sørensen

We do bio-sensing with color-centers in diamond.

In one line of research, we study the linkage between intracellular mechanics and biochemical properties within the cell, for example through signaling evidenced by free radicals. The former is measured by means of optical trapping, the latter by means of so-called T1-relaxometry, inspired by traditional NMR methodology. We can use both methods at once since in both cases, the probe particle is a nanodiamond with embedded color centers, so-called NV-centers. The nanodiamonds are typically around 50-120 nm in diameter and are naturally engulfed by the single cells which we study.

In another line of research, we explore biosensing with diamond crystals enriched by a surface layer of NV-centers and position the biologically relevant object on top of the crystal.

In both cases, our ultimate target is to do nanoscale-NMR on or inside cells by means of the NV-centers in either the nanodiamonds or the diamond crystal. We are driven by method development for a deeper understanding of details of cellular life.

Magnetic Resonance by Optics group

Ongoing research projects

Intracellular mechanics and nanodiamond sensing

Left: Principle of the measurement assays in the optical setup. Right: Illustration of study of uptake of nanodiamonds by monocytes as function of time. Sketches by Maria Niora and Kirstine Berg-Sørensen
Nanodiamond sensing in THP-1 monocytes and derived cells

The project aims to demonstrate simultaneous sensing of viscoelastic properties of the cellular cytoskeleton along with intracellular diamond sensing. The project is interdisciplinary as it involves aspects ranging from instrument and assay development to quantitative single cell biology..

Sensing free radicals in the scarred hearts

Left: Sketch of the overall principle of diamond sensing in cardiac fibroblast cells or in myofibroblast cells. Right: Sketch illustrating the principle of combined force spectroscopy and nanodiamond sensing in the form of T1-relaxometry. Figure by Aldona Mzyk.
The project aims to simultaneously map the mechanical properties and the existence of free radicals inside cardiac cells, with the goal to explore the mechanobiological processes during development of scars in the heart. 

Micron-scale NMR with NV centers in diamond and enhanced by dDNP-hyperpolarization

Overall sketch of the principle of hyperpolarization-enhanced NMR spectroscopy by means of NV centers in diamond. The assay may be applied for NMR of both biomolecules and of single cells. Figure by Luca Troise.

Cell metabolism at the micron scale
The project aims to develop micron-scale NMR by means of NV centers in a diamond crystal, and enhance the NMR signal with dissolution DNP. The ultimate goal is to use the equipment which we develop for studies of metabolism in single cells.

Group Leader

Kirstine Berg-Sørensen

Kirstine Berg-Sørensen Groupleader, Associate Professor Department of Health Technology Mobile: +45 22275868

Kirstine Berg-Sørensen is associate professor in biological physics. Her earliest research experience dealt with quantum mechanical and semi-classical models of laser cooled atoms and the physics of such laser cooled atoms while she in 1999 changed direction to biological physics. This change was kick-started by a 6Mkr grant from the Danish Research Agencies to initiate the first optical tweezers activity in Denmark, at the Niels Bohr Institute, University of Copenhagen. Within biological physics, in particular analysis and models of data from single molecule experiments, both in in vitro and in vivo systems, has caught her interest. Her main emphasis has been on experiments conducted using optical tweezers, optical traps in microfluidic systems and with micro-particle-velocimetry.

At DTU Health Tech, she focuses on experimental work to couple biophysics and optical trapping in biological systems with quantum sensing by means of color centers in diamonds. These activities have received support from the Carlsberg Foundation, the Independent Research Fund Denmark, and the Novo Nordisk Foundation. Further, her lab hosts experiments to develop NMR spectroscopy with color centers in diamond and enhanced by dissolution DNP. This work is supported by an ERC Synergy grant (headed by a colleague in the Department). Additional funding to the group is provided by a Marie Curie COFUND postdoc grant.

Apart from her research activities, Kirstine Berg-Sørensen is an active teacher and has at DTU served as Head of Studies for the MSc education in Physics and Nanotechnology.

Updates on Linkedin


  • Alexander Huck, DTU Physics
  • Nir Bar-Gill, Hebrew University
  • Fedor Jelezko, Uni Ulm
  • Romana Schirhagl, Uni Groningen
  • Johan Ulrik Lind, DTU Health Tech 
  • Giovanni d'Angelo, EPFL
  • Alicia Lundby, Uni Copenhagen