Noninvasive Detection and Thermal Ablation Therapy of Endometriosis Using Silica-Coated Gold Nanorods

Endometriosis (EM) is a gynecological disease where endometrial tissue grows outside the uterus. Current diagnostic methods are mainly through surgical visualization with histological verification; there's a need for noninvasive approaches. Herein, we report photoacoustic imaging (PAI) can be a noninvasive imaging modality for deep-seated EM by employing FITC-tagged, silica-coated gold nanorods (AuNR@Si(F)-PEG) as the contrast agent. When the nanoparticles are injected intravenously into mice with EM, the strong PA signals from AuNRs are detected from the EM tissues by particle accumulation in the EM lesions through the enhanced permeability and retention effect. Additionally, due to the presence of FITC, the NPs facilitate easy identification and isolation of endometriosis tissue under a fluorescence dissection microscope. Owing to the high photothermal ablation property of AuNRs, the NPs can be used for laser-induced thermal ablation therapeutics to shrink the endometriosis lesions, validated by imaging, pro-apoptotic marker cleaved caspase-3, and H&E staining. This technique provides new avenues for studying endometriosis development, progression, and the related treatment modalities.