Nitrogen-Vacancy color center in diamond—emerging nanoscale applications in bioimaging and biosensing

Abstract

1Nitrogen-Vacancy (NV) color center in diamond is a flourishing research area that, in recent years, has displayed remarkable progress. The system offers great potential for realizing futuristic applications in nanoscience, benefiting a range of fields from bioimaging to quantum-sensing. The ability to image single NV color centers in a nanodiamond and manipulate NV electron spin optically under ambient condition is the main driving force behind developments in nanoscale sensing and novel imaging techniques. In this article we discuss current status on the applications of fluorescent nanodiamonds (FND) for optical super resolution nanoscopy, magneto-optical (spinassisted) sub-wavelength localization and imaging. We present emerging applications such as single molecule spin imaging, nanoscale imaging of biomagnetic fields, sensing molecular fluctuations and temperatures in live cellular environments. We summarize other current advances and future prospects of NV diamond for imaging and sensing pertaining to bio-medical applications.

Enhanced photoelectric detection of NV magnetic resonances in diamond under dual-beam excitation

“…The negatively charged nitrogen-vacancy (NV -) center in diamond has attracted particular attention as a room temperature solid-state qubit [1] that can be read out by optical detection of magnetic resonances (ODMR) [2]. Numerous applications in the field of solid-state quantum information processing [3] and sensing [4][5][6][7][8][9][10] are being studied.We have recently developed a method for the photoelectric detection of NV -electron spin magnetic resonances (PDMR) [11], performed directly on a diamond chip equipped with electric contacts and based on the electric detection of charge carriers promoted to the diamond conduction band (CB) by two-photon ionization of NV -under green illumination (single-beam PDMR, or s-PDMR) (Fig. 1) To explore the photophysics behind the PDMR scheme and optimize its performances, we performed ab initio calculations of N 0 s , NV -, and NV 0 ionization cross sections, and compared the results to experimental characterizations of the ionization bands.…”

“…The negatively charged nitrogen-vacancy (NV -) center in diamond has attracted particular attention as a room temperature solid-state qubit [1] that can be read out by optical detection of magnetic resonances (ODMR) [2]. Numerous applications in the field of solid-state quantum information processing [3] and sensing [4][5][6][7][8][9][10] are being studied.…”

Near-Infrared Fluorescence from Nanodiamond for Multimodal Bioimaging

“…The most well-studied and utilized defect to date is nitrogen-vacancy (NV) color centers which appear in neutral (NV 0 ) and negative (NV -) charge states with zerophonon lines (ZPL) at 575 nm (2.156 eV) and 637 nm (1.945 eV), respectively [3,5,7]. NV color centers emit stable emission with broad spectral ranges at room temperature and are recently used for bioimaging and biosensing [8]. However, the limitation is the fluorescence wavelength predominantly are between 400 to 550 nm, this overlaps with most biomolecules that absorb light between 280 to 500 nm ranges [9], some obstacles do exist for bioapplications using NV centers.…”

“…Synthetic diamond grown by the high-pressure hightemperature technique uses a nickel-containing metallic catalyst, and nickel is usually inevitably included in the resulting diamond. Particularly, dispersed nickel atoms can be incorporated in diamond producing color centers with emission in the infrared region, result in the 1.4 eV Ni-related center (with ZPL near 885 nm) with negative nickel ion in the center of a diamond divacancy, and nickel-nitrogen complex NE 8 with ZPL at 796 nm formed by a substitutional nickel atom with four adjacent nitrogen atoms using chemical vapor deposition (CVD) method. It is also possible to fabricate single nickel-nitrogen defects in diamond [11].…”

Versatile Multicolor Nanodiamond Probes for Intracellular Imaging and Targeted Labeling

“…[7][8][9] To date, there is abundance of research on the application of FNDs containing nitrogen-vacancy (NV) defects for bioimaging and drug delivery. [10][11][12][13][14][15][16][17] However, NV FNDs have excitation and emission in visible range that can contribute to tissue absorption and auto-fluorescence. Therefore, FNDs containing centers with narrowband emission at the near IR (NIR) spectral range are particularly advantageous to achieve a better signal to noise ratio imaging for long term cellular imaging.…”