Polymerically modified superparamagnetic iron oxide nanoparticles as a multi-model molecular probe for functionalized optical coherence tomography

We demonstrate the synthesis, characterization, and potential application of polymerically modified superparamagnetic nanoparticles over bare SPIONs, as a multi-model molecular probe for functionalized optical coherence tomography (fOCT). The synthesized magnetic nanoparticles (MNPs) also have the ability of photo thermionic excitation under near-infrared irradiation (980 nm). By having dual excitation properties, the SPIONs are used as exogenous contrast agents for magnetomotive optical coherence tomography (MMOCT) as well as photothermal optical coherence tomography (PTOCT). We developed a functionalized OCT system and signal processing algorithms for MMOCT and PTOCT. Further, non-invasive in-vivo imaging was performed on swiss-albino mice to demonstrate the potential application of polymerically modified SPIONs. A diffusion dynamics study and contrast-to-noise ratio (CNR) study of the dispersed synthesized SPIONs inside skin tissue of mice as a function of time and depth is also reported. We found that PEG-SPIONs are excellent candidate for molecular contrast agent of functional OCT.