Recent advancements in bioengineering have seen the development of a groundbreaking class of molecular quantum nanosensors (MoQNs) that have the ability to operate within living cells. This innovative research, conducted by teams from the National Institutes for Quantum Science and Technology (QST) and The University of Tokyo in collaboration with Kyushu University, offers new possibilities for understanding cellular environments.

Overview of the Research

The study published in Science Advances demonstrates how MoQNs can facilitate accurate temperature measurements and detect radical-related spin signals in living cancer cells. These nanosensors operate with unparalleled specificity, showcasing their potential as vital tools in biomedical research.

Challenges in Cellular Sensing

Quantifying physical and chemical states within living cells has historically been a daunting challenge in modern biology. Existing intracellular quantum sensors such as nanodiamonds, quantum dots, and fluorescent proteins, while effective, suffer from limitations related to:

  • Material heterogeneity: Inconsistencies in sensor materials can lead to variable results.
  • Thermometric specificity: Difficulty in achieving precise temperature measurements.
  • Biocompatibility: Ensuring that sensors do not adversely affect cellular health.

To address these challenges, the research team engineered MoQNs from pentacene molecular spin qubits embedded in para-terphenyl nanocrystals, coated in the biocompatible surfactant Pluronic F127. This innovative design not only provides molecular-level uniformity but also preserves quantum coherence under physiological conditions.

Validation of Cellular Compatibility

The researchers validated the capability of MoQNs to be introduced into live cells without compromising cell viability. Through extensive testing, they found that cells containing MoQNs maintained:

  • Plasma membrane integrity
  • Metabolic activity
  • Normal cell-cycle progression

Moreover, MoQNs exhibited robust quantum functionalities inside the cells, including continuous-wave optically detected magnetic resonance (ODMR) detection, Rabi oscillations, spin-echo measurements, and T1 relaxometry.

High-Precision Temperature Mapping

Using deuterated MoQNs (dMoQNs), the researchers achieved precise temperature sensing within the cytoplasm of live cancer cells, observing that intracellular temperatures were consistently higher than those of the surrounding medium. Additionally, they extended their methodology to organelle-specific measurements, successfully mapping temperatures within the nuclei of living cancer cells and revealing localized thermal heterogeneity.

Measurement Area Temperature Range Significance
Cytoplasm ~37.5°C Higher than surrounding medium, indicative of cellular activity.
Nucleus Variable, depending on location Demonstrates thermal heterogeneity within the nucleus.

Probing Radicals and Future Applications

Beyond temperature sensing, the MoQN platform also demonstrated the ability to detect radical-related external spins within living cells. By inducing radical-generating conditions using hydrogen peroxide, significant spot-dependent changes in spin relaxation and coherence were observed both in the cytoplasm and nucleus. This capability implies that MoQNs can effectively monitor intracellular redox environments as well as temperature variations.

“This work shows that MoQNs can operate directly inside living cells while maintaining the precision needed for absolute thermometry,” remarks Dr. Ishiwata, Team Leader of the Quantum Bioengineering Team at QST. “We believe this opens a new route toward quantitative quantum measurement of intracellular environments.”

Conclusion

The development of MoQNs has the potential to revolutionize the fields of nanoscale thermometry and biochemical sensing within biological systems. With their molecular-level tunability, biocompatibility, and reliable performance under physiological conditions, MoQNs pave the way for future quantum-enabled biological and medical measurements.

Publication Details

Molecular Quantum Nanosensors Functioning in Living Cells, Science Advances (2026).

For more information, visit the original research article.

Relevant Topics

This advancement could greatly enhance our understanding of cellular mechanisms and the development of targeted therapies in areas such as cancer treatment and regenerative medicine.