In a groundbreaking advancement merging quantum technology with cellular biology, researchers have engineered a multi-plane wide-field microscope that enables volumetric, three-dimensional quantum sensing within biological systems using fluorescent nanodiamonds (FNDs). This innovative optical platform transcends the long-standing limitation of two-dimensional wide-field quantum sensing techniques, offering unprecedented access to nanoscale intracellular processes in their full spatial complexity.
The heart of this technological leap lies in its ability to simultaneously image eight focal planes across a vertical span of 5 micrometers while covering a lateral area of 50 by 50 micrometers. Traditional wide-field microscopes capture a single focal plane at a time, constraining observations to flat, two-dimensional sections which omit critical depth information intrinsic to biological function. By integrating a beam-splitting prism into the optical path, the system effectively partitions the emitted fluorescence into multiple depth-resolved images captured concurrently. This allows real-time, volumetric acquisition without necessitating mechanical scanning along the z-axis, thereby preserving temporal resolution essential for dynamic biological phenomena.
The microscope’s design capitalizes on the Coherent Verdi G5 laser source, whose stable, high-intensity illumination ensures robust excitation of the nitrogen-vacancy (NV) centers in the nanodiamonds. These NV centers, renowned for their quantum coherence even in ambient conditions, serve as atomic-scale sensors that respond to minute variations in magnetic and electric fields, temperature, and strain with exceptional sensitivity. Coupled with a high numerical aperture objective (Olympus LUCPLFLN40X), the system optimizes photon collection efficiency, critical for maintaining signal integrity across multiple focal depths.
Achieving nanometer-scale localization in three dimensions required the development of a sophisticated fluorescent particle positioning method based on Fourier-transform principles. By transforming spatial fluorescence distributions into frequency domain signatures, the algorithm deciphers subtle position-dependent phase shifts in the emitted light. This yields a lateral localization precision as fine as 9 nanometers and axial accuracy down to 12 nanometers—a remarkable feat surpassing the diffraction limits typical of conventional optical microscopy. The implementation of this computational approach enables precise tracking of individual intracellular nanodiamonds amidst the complex and heterogeneous cellular environment.
Experimental validation was conducted in mouse cardiomyocytes, where the researchers introduced FNDs as intracellular quantum probes. Utilizing the developed multi-plane microscope, they successfully performed correlated 3D mapping of these nanoparticles within the cellular architecture. Subsequent optically detected magnetic resonance (ODMR) measurements were performed on NV centers nestled inside the FNDs, revealing detailed local magnetic field distributions within the cytoplasm. This dual capability of spatial positioning combined with quantum sensing within living cells demonstrates a powerful new modality for biological investigation.
Importantly, the platform’s volumetric imaging capacity enables continuous single-particle tracking within a three-dimensional cellular context. This capability is pivotal for unraveling dynamic intracellular transport mechanisms, molecular interactions, and spatial heterogeneities at the nanoscale—domains previously obscured in two-dimensional snapshots. The potential to monitor magnetically sensitive quantum markers in living cells over time opens avenues for high-resolution studies of physiological and pathological processes with quantum-enhanced sensitivity.
Moreover, this work underscores the practical feasibility of applying wide-field quantum sensors beyond traditional physics laboratories into mainstream biomedical research. The non-invasive nature of FND probes, coupled with their biocompatibility and photostability, promotes long-term intracellular studies without compromising cell viability, overcoming limitations posed by organic fluorescent dyes prone to photobleaching. The ability to measure physical parameters like magnetic fields and temperature inside living cells with nanometric precision stands to revolutionize the diagnostic and therapeutic landscape.
The integration of a beam-splitting prism to simultaneously access multiple imaging planes marks a technical milestone in optical microscopy, bridging the gap between wide-field speed and confocal or multiphoton depth-sectioning resolution. This hybrid approach balances the need for rapid, high-throughput imaging with the spatial discrimination necessary to resolve complex intracellular environments. As quantum sensors evolve, coupling them with sophisticated microscopy architectures is fundamental to unlocking their full potential in life sciences.
This innovative platform’s implications extend far beyond cardiomyocytes. Its adaptability suggests potential applications in neuroscience, immunology, and cellular biomechanics, where spatially resolved quantum sensing could elucidate subtle physico-chemical cues critical for cellular function and signaling. Furthermore, the capability to perform in vivo quantum magnetic resonance measurements at subcellular resolution foreshadows transformative insights into diseases rooted in dysregulated ionic fluxes and magnetic field anomalies.
Looking ahead, continued refinement of this multi-plane quantum imaging system could involve scaling up imaging volume, enhancing temporal resolution, and integrating complementary contrast mechanisms. Implementing adaptive optics to correct sample-induced aberrations and deploying machine learning algorithms for real-time data processing may further boost localization performance and sensing fidelity. Such advancements will propel the platform toward routine application in complex biological models and clinical diagnostics.
In conclusion, this development in multi-plane wide-field microscopy coupled with quantum sensing via intracellular fluorescent nanodiamonds heralds a new era of nanoscale bioimaging. By capturing fast, volumetric, and quantum-sensitive observations within living cells, this technology bridges disciplines of quantum physics, optics, and cell biology, presenting unprecedented opportunities to decode the intricacies of life at the quantum frontier.
Subject of Research: Not applicable
Article Title: 3D positioning and optically detected magnetic resonance of intracellular fluorescent nanodiamonds using a multi-plane microscope
News Publication Date: 1-Feb-2026
Web References: http://dx.doi.org/10.52601/bpr.2025.250012
Image Credits: HIGHER EDUCATION PRESS
Keywords: Cell biology
Tags: 3D quantum sensing in biological systemsbeam-splitting prism optical designCoherent Verdi G5 laser excitationfluorescent nanodiamonds intracellular imaginghigh-resolution quantum microscopymulti-plane wide-field microscopynanoscale intracellular process visualizationnitrogen-vacancy centers quantum sensorsoptical magnetic resonance microscopyquantum technology in cellular biologyreal-time volumetric fluorescence acquisitionvolumetric imaging without mechanical scanning
