25-30 August 2019
Henry Ford Building
Europe/Berlin timezone

13C Longitudinal Relaxation Times for Advanced Applications of Nanodiamonds in Medicine

Not scheduled
4h
Harnack House and Henry Ford Building

Harnack House and Henry Ford Building

Board: 479
Poster Posters

Speaker

Dr Pavleta Tzvetkova (Institute of Organic Chemistry and Institute for Biological Interfaces 4 – Magnetic Resonance, Karlsruhe Institute of Technology)

Description

Nanodiamonds (NDs) are a subject of increased application interest based on the possibilities of their use in medical imaging [1] and as drug delivery systems [2, 3]. Fluorescent NDs are addressed as they emit single-photon luminescence due to a number of optically sensitive paramagnetic defects, particularly nitrogen-vacancy centres. The knowledge on how the defect types and distribution in the structure affects the relaxation is of crucial importance as they affect the physical properties of the NDs and play an important role in the choice of NDs types.

The pure diamonds have long 13C spin lattice relaxation times, measured with NMR, due to the low 13C natural abundance. On the other hand, the presence of defects in the diamonds, either inherent or intentionally induced allows additional relaxation pathways and thus accelerates nuclear relaxation. The most common natural paramagnetic defects in diamonds include sp3-type dangling bonds on carbons, and single nitrogen substitutions known as P1 centres.

We investigated the dependence of the 13C longitudinal relaxation times of a series of non-fluorescent and fluorescent NDs in solid state and in solution. Severe change in the linewidths for the non-fluorescent to the fluorescent NDs as powder samples and upon their solution was observed. The 13C longitudinal relaxation times of the NDs were measured with saturation recovery experiment and the obtained values from the exponential data fitting were compared.

References:
1. Nat. Commun. 6:8459 doi: 10.1038/ncomms9459 (2015).
2. Crit. Rev. Solid State Mater. Sci., 34:18–74 (2009).
3. Int. J. Nanomed., 8:203–220 (2013).

Primary authors

Dr Pavleta Tzvetkova (Institute of Organic Chemistry and Institute for Biological Interfaces 4 – Magnetic Resonance, Karlsruhe Institute of Technology) Christian Jentgens (Microdiamant AG) Ilai Schwarz (NVision Imaging Technologies GmbH and Institute of Theoretical Physics, Ulm University) Prof. Martin Plenio (NVision Imaging Technologies GmbH and Institute of Theoretical Physics, Ulm University) Prof. Burkhard Luy (Institute of Organic Chemistry and Institute for Biological Interfaces 4 – Magnetic Resonance, Karlsruhe Institute of Technology)

Presentation Materials

There are no materials yet.