A fluorescent nanodiamond foundation for quantum sensing in cells

Free radicals play a major role in the aging process as well as a most diseases. However, we barely know anything about them. These tiny molecules have an extremely short lifespan and are difficult to measure, while their role in health related processes is considerable. Fluorescent nanodiamonds are very small diamonds which can shed a light on this research question. These diamonds emit a constant light in a controlled setting. This is possible due to a small defect in the structure of the diamond, which makes it fluorescent. When free radicals are present, the light changes, which allows measurement of the radicals. During my PhD I have laid the basis for these biological measurements. Not all cells automatically take up diamonds or the diamonds tend to aggregate in cellular medium. By changing the solutions in which we administer the diamonds, we can prevent these obstacles. I have also performed a very detailed analysis of the cellular response on diamond uptake. Conveniently, the cells hardly show any response to the diamond uptake, an important result for our future measurements. In addition, I have developed new ways of targeting the diamonds to specific places in the cells, to obtain location specific information. Finally I have determined the subcellular location of the diamonds using a new technique, based on integrated electron microscopy. During my work I have laid the foundation for promising cellular research of ageing and disease using fluorescent nanodiamonds

Improving surface and defect center chemistry of fluorescent nanodiamonds for imaging purposes-a review

Diamonds are widely used for jewelry owing to their superior optical properties accounting for their fascinating beauty. Beyond the sparkle, diamond is highly investigated in materials science for its remarkable properties. Recently, fluorescent defects in diamond, particularly the negatively charged nitrogen-vacancy (NV-) center, have gained much attention: The NV- center emits stable, nonbleaching fluorescence, and thus could be utilized in biolabeling, as a light source, or as a Forster resonance energy transfer donor. Even more remarkable are its spin properties: with the fluorescence intensity of the NV- center reacting to the presence of small magnetic fields, it can be utilized as a sensor for magnetic fields as small as the field of a single electron spin. However, a reproducible defect and surface and defect chemistry are crucial to all applications. In this article we review methods for using nanodiamonds for different imaging purposes. The article covers (1) dispersion of particles, (2) surface cleaning, (3) particle size selection and reduction, (4) defect properties, and (5) functionalization and attachment to nanostructures, e.g., scanning probe microscopy tips

Editorial: HIV-1 genetic diversity, volume II

EditorialS