Quantum-Enhanced Optical Monitoring of Bone Marrow–Derived and Pluripotent Stem Cells at 1 µm Resolution Using Squeezed-Light Interferometric Microscopy v1

We report the experimental implementation of a quantum-enhanced interferometric microscopy platform for monitoring mesenchymal stem cells (MSCs), induced pluripotent stem cells (iPSCs), and bone marrow–derived stem cells (BMSCs) at 1 µm spatial resolution. A 5.1 dB quadrature-squeezed illumination source was integrated into a phase-stabilized Mach–Zehnder interferometer coupled with high-NA microscopy optics and sCMOS detection. The system achieves a 1.76× phase sensitivity improvement beyond the shot-noise limit (SNL), corresponding to a 2.8× signal-to-noise ratio enhancement in live-cell imaging. Sub-micron refractive index sensitivity (5.2 × 10⁻⁴ RIU) enabled early detection of mitochondrial remodeling and cytoskeletal disorganization in differentiating and stress-induced stem cells. These results demonstrate the translational potential of quantum-enhanced optical metrology in regenerative medicine and stem cell monitoring.