The long-dreamed-of capability of monitoring the molecular machinery in living systems has not been realized yet, mainly due to the technical limitations of current sensing technologies. However, recently emerging quantum sensors are showing great promise for molecular detection and imaging. One of such sensing qubits is the nitrogen-vacancy (NV) center, a photoluminescent impurity in a diamond lattice with unique room-temperature optical and spin properties. This atomic-sized quantum emitter has the ability to quantitatively measure nanoscale electromagnetic fields via optical means at ambient conditions. Moreover, the unlimited photostability of NV centers, combined with the excellent diamond biocompatibility and the possibility of diamond nanoparticles internalization into the living cells, makes NV-based sensors one of the most promising and versatile platforms for various life-science applications. In this review, we will summarize the latest developments of NV-based quantum sensing with a focus on biomedical applications, including measurements of magnetic biomaterials, intracellular temperature, localized physiological species, action potentials, and electronic and nuclear spins. We will also outline the main unresolved challenges and provide future perspectives of many promising aspects of NV-based bio-sensing.

College of Polymer Science and Engineering College of Biomedical Engineering State Key Laboratory of Polymer Materials and Engineering Sichuan University 610065 Chengdu China

Department of Electrical and Electronic Engineering Joint Appointment with School of Biomedical Sciences The University of Hong Kong Pokfulam Road Hong Kong China

Department of Electrical and Electronic Engineering The University of Hong Kong Pokfulam Road Hong Kong China

Institute of Organic Chemistry and Biochemistry Czech Academy of Sciences 166 10 Prague Czech Republic

National Engineering Research Center for Nanomedicine Key Laboratory of Molecular Biophysics of Ministry of Education Hubei Key Laboratory of Bioinorganic Chemistry and Materia Medical College of Life Science and Technology Huazhong University of Science and Technology 430074 Wuhan China

UGC DAE Consortium for Scientific Research Kolkata Centre Sector 3 LB 8 Bidhan Nagar Kolkata 700106 India

References provided by Crossref.org

Transition in morphology and properties in bottom-up HPHT nanodiamonds synthesized from chloroadamantane

Nanodiamond-Quantum Sensors Reveal Temperature Variation Associated to Hippocampal Neurons Firing

Dynamic nitrogen vacancy magnetometry by single-shot optical streaking microscopy

Quantum Sensing of Free Radicals in Primary Human Dendritic Cells