Advances in intracellular temperature measurements with NV colour centres in diamond (Invited Paper)

Intracellular temperature is a crucial parameter that influences metabolic processes, enzymatic activity, and cellular signaling. Advances in nanoscopic thermometry using nitrogen-vacancy (NV) centers in diamond provide unprecedented precision in mapping temperature variations within living cells. NV centers, atomic-scale defects in the diamond lattice, exhibit quantum properties sensitive to temperature, enabling non-invasive and high-resolution thermal measurements. These properties, combined with the biocompatibility and stability of nanodiamonds, make them ideal for probing cellular thermodynamics in real time. By integrating NV-based thermometry with multi-electrode array (MEA) techniques, it is possible to correlate intracellular temperature variations with changes in cellular metabolism and electrophysiological activity. This combination offers unique insights into how metabolic processes influence cellular function, particularly under varying physiological and pathological conditions. For example, mapping temperature heterogeneity within cellular microenvironments can shed light on mitochondrial thermogenesis or metabolic alterations in disease states. This approach also holds promise for studying the role of intracellular temperature in the development and progression of neurodegenerative diseases, where metabolic dysfunction is a peculiar indicator. Another intriguing application could involve the functionalization of nanodiamonds to target specific organelles, enabling even more precise investigations of localized thermal dynamics in the future. For now, current advancements in NV-based thermometry already demonstrate its robustness as a tool for exploring the dynamic interplay between intracellular temperature and metabolism. These insights provide a foundation for advancing our understanding of cellular energetics and for developing innovative approaches in diagnostics and therapeutics.