Light-mediated theranostic platforms involve the use of agents (small molecules/nanomaterials) that can absorb light to produce heat or reactive chemical species (RCS), as well as emit fluorescence. These platforms are advantageous in personalized medicine, offering enhanced diagnostic capabilities, improved therapeutic efficiencies, and the ability to monitor treatment outcomes using imaging modalities. Agents that absorb near-infrared (NIR) light provide minimal scattering, low autofluorescence, superior spatio-temporal resolution, and deeper tissue penetration depths. Gold nanorods (GNR) and indocyanine green (ICG) are two such agents known for their NIR light absorption properties. GNR offers tunable plasmonic properties, while ICG is an FDA-approved NIR fluorophore.

However, the use of ICG and GNR is hampered by various limitations, including photobleaching, non-specificity, toxicity, and aggregation in solution. To overcome these challenges, we present NIR light-activatable niosomes loaded with GNR and ICG for cancer theranostic applications. Both agents were encapsulated into biocompatible niosomes based on non-ionic surfactants to form ICG-GNR@Nio, achieving superior loading efficiencies and enhanced properties. ICG-GNR@Nio exhibits excellent storage stability, photostability, elevated temperature rise, and generation of reactive oxygen species (ROS) upon 1064 nm laser irradiation.

Subsequently, the enhanced phototherapeutic capabilities of ICG-GNR@Nio were validated in in vitro cellular experiments. Overall, ICG-GNR@Nio-based theranostic platforms represent a significant advancement in improving diagnosis and therapeutic capabilities for biomedical clinicians in combating various diseases.