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bioRxiv · 10.1101/2025.07.27.666994

Tracking Chemotherapy-Induced Oxidative Stressin Glioblastoma Cells Using NV-Based QuantumSensors

Parhi, J.·Ghosh, A.·Zaveri, D.·Majumder, A.·Saha, S.·Tallur, S.·Saha, K.
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Abstract

Glioblastoma (GBM) is a highly aggressive cancer with poor prognosis despite temozolomide(TMZ) treatment. TMZ induces oxidative stress, causing persistent redox alterations. We report the first use of nitrogen-vacancy centers in nanodiamonds as quantum sensors for T1 relaxometry in fixed GBM cells, detecting stable paramagnetic signatures linked to chemotherapy-induced persistent oxidative damage. U87-MG cells treated with TMZ show dose-dependent T1 shortening, consistent with conventional ROS fluorescence assays. TBHP studies confirm that the T1 response reflects accumulated redox adducts. Measurements remain robust across fixation and permeabilization protocols. Since drug-resistant GBM cells preserve antioxidant signatures, unchanged T1 times after treatment may indicate early resistance phenotypes. This fixed-tissue compatible readout could stratify patient response, guide adaptive therapy, and support biopsy-based diagnostics and post-treatment drug analysis in routinely preserved clinical specimens enabling retrospective studies and better outcomes for future personalized oncology decision making pathways.

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Parhi, J., Ghosh, A., Zaveri, D., Majumder, A., Saha, S., Tallur, S., Saha, K.. 2025-07-31. Tracking Chemotherapy-Induced Oxidative Stressin Glioblastoma Cells Using NV-Based QuantumSensors. https://doi.org/10.1101/2025.07.27.666994

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