Nanophotonic catheters: A lens into the body for biosensing and biomedical imaging

Optical biosensors integrated into catheter systems enable highly sensitive, multiplexed, and real-time detection of biochemical analytes and physiological parameters within the body through minimally invasive approaches. Fiber optic sensing modalities, such as fiber Bragg gratings, fluorescence, Raman spectroscopy, and confocal microscopy, have shown remarkable capabilities in measuring pressure, temperature, force, molecular composition, and mapping tissue microstructures via compact catheter devices. However, translating these advantages into widespread clinical use requires overcoming the challenges of miniaturization, biocompatibility, reliable signal acquisition, and seamless integration without compromising catheter functionality. Recent innovations have leveraged nanotechnology and materials science to develop next-generation smart-optical-sensor catheters. Nanoparticle coatings endow optical fibers with enhanced sensing performance, enabling ultrasensitive plasmonic biodetection and multiplexed fluorescence monitoring. Multifunctional nanocomposites that exhibit complementary properties catalyze multimodal catheter imaging and localization. Looking ahead, machine learning approaches applied to large multi-parametric datasets could provide new clinical insights. Implantable wireless optoelectronic catheters integrated with drug delivery systems present opportunities for theranostic closed-loop systems. Ultimately, interdisciplinary research across photonics, nanotechnology, bioelectronics, AI, and translational medicine are critical to realizing the transformative potential of optical biosensor catheters for robotic surgical guidance and autonomous interventions.