Integrating tumor hypoxic sensing and photothermal therapy using a miniaturized fiber-optic theranostic probe

Abstract Efficient delivery of photons to visceral organs is critical for the treatment of deep-seated tumors taking advantage of photo-theranostics. Optical fiber can be regarded as a direct and facile photon pathway for targeting tumor lesion with negligible body invasion. However, current fiber theranostic strategies rely on the spatially separated optical fibers to realize diagnosis and therapy independently, resulting in low compactness, poor continuity of medical process, and incompatibility with current medical technologies. Herein, we develop an integrated fiber-optic theranostic (iFOT) probe that merges tumor microenvironment (TME) sensing and photothermal therapy (PTT) by functionalizing the fiber with graphene/gold nanostar hybrid materials and hypoxic-responsive fluorophores. The iFOT probe can quickly detect the hypoxia of xenograft tumors of mice with high sensitivity. The tumors can be photothermally killed on-site through the same fiber probe tightly followed by detection, which presents a high cure rate without the risk of recurrence. More importantly, the iFOT is highly adaptable to the conventional medical imaging and endoscopic techniques, such as laparoscope, magnetic resonance imaging, and ultrasound imaging, which facilitates the imaging-assisted navigation and manipulation by use of the interventional trocar. The proposed integrated fiber-optic theranostic strategy can be used as an effective endoscopic and interventional tool for tackling deep-situated tumor and may open a revolutionized pathway to bridge the separate diagnosis and therapy process in the current stage.