Optical coherence tomography with enhanced contrast using oriented magnetic nanorods

In recent years, the utilization of nanoparticles with varying morphologies in optical coherence tomography (OCT) has gained prominence, primarily aimed at enhancing imaging contrast and depth. Various factors associated with nanoparticles, encompassing their shape, orientation, and distribution within biological tissues, significantly influence OCT performance. A thorough investigation of these parameters has yielded substantial findings, particularly regarding the enhancement of OCT images facilitated by the presence of nanorods (NRs). In this study, we conducted OCT imaging of chicken breast tissue employing Fe₃O₄ NRs under different polarization states, utilizing solenoids to apply a magnetic field to the nanoparticles. The results demonstrate that orienting nanoparticles can improve the Contrast-to-Noise Ratio (CNR) and signal-to-noise ratio (SNR) of OCT signal more than twofold compared to scenarios lacking specified orientation. Furthermore, this article addresses the challenge of prolonged nanoparticle distribution in tissue when using ultrasound probes, successfully reducing the distribution time from approximately 45 min to about 5 min. The findings presented herein show significant promises for advancing optical coherence tomography across a variety of applications.