德国杜塞尔多夫大学医学物理学/医学生物化学研究博士后职位

Introduction:

Nanodiamonds are diamond crystals with sizes in the range of a few nanometers to a few 100 nm in diameter. Omnipresent defects in nanodiamonds can be excited by a laser to fluoresce in the red or other spectral regions. This fluorescence is intense, and, in contrast to other fluorescent labels, does not exhibit photobleaching.

The combination of three salient features makes nanodiamonds an extremely powerful novel approach to biological sensing and imaging.

First, nanodiamonds have been shown to be nontoxic if their size is not too small. Nanodiamonds can be inserted in cells which continue with normal activity. Again, this is in contrast to other nanoparticles investigated recently, such as quantum dots.

Second, the surface of nanodiamonds can be functionalized so that a large variety of molecules can be bound to it. These molecules can be chosen to bind to desired target molecules in cells. These functionalized nanodiamonds then serve as biomarkers.

Third, the flurorescent defects have a spin structure that allows optically detected magnetic resonance. The resonance frequency is modified by an applied magnetic field. If a spatially varying magnetic field gradient is applied to a specimen, the position of the nanodiamonds previously injected and bound to target molecules, can be determined by its magnetic resonance frequency. This means that optically detected magnetic resonance imaging is possible. Similar to conventional MRI, it is possible to image deep inside a body, in a non-invasive manner. Different from conventional MRI, the detection is done by ultrasensitive photon detection, and thus even very low concentrations of nanodiamonds are detectable.



In this project, the goal is to

(1) build an optical magnetic resonance imaging system for detecting functionalized nanodiamonds even deep in tissue. Tests will be performed on phantoms in strongly scattering media such as chicken breast.

(2) develop techniques to functionalize nanodiamonds so that they become markers for pathologies of interest, e.g. endometriosis and tumors. The functionalization and imaging will be studied and verified on cell cultures.



If appropriate permission is obtained, this work can be extended to tests on humans.