Plasmon-Resonant Nanorods as Contrast Agents

描述（由申请人提供）：将使用新兴的生物医学成像方法（光学相干断层扫描或OCT）和新型造影剂（功能化金纳米棒），开发一种集成的微创方法，用于检测，诊断和治疗病变状态下的细胞和组织。OCT能够在近红外（NIR）下进行细胞分辨率成像，并且具有在疾病早期诊断异常细胞和组织的潜力，给予足够的对比度。各向异性金纳米棒表现出可调谐的等离子体响应，可以在选择的近红外频率下进行强吸收或散射，从而提高OCT和相关技术的灵敏度和范围。新的OCT方法将基于增强的各向异性纳米棒在孤立或聚集形式的光学对比度。具有强选择性近红外消光能力的金纳米棒将被生物分子配体功能化，用于选择性靶向生物标志物表达异常的组织。这些将通过结合细胞表面标记物或通过细胞摄取作为定点光学标记。带有磁性尖端的纳米棒可以在组织内提供额外的位置和方向控制，并促进一种新的动态OCT方法的发展。金属纳米棒还可以支持极大的吸收截面，并产生高度局部化的热梯度，并可用于在低辐射功率下增强光诱导热疗。提出的纳米棒增强OCT成像系统将首先应用于组织幻象，然后应用于仓鼠颊袋模型局部热疗的体内肿瘤细胞检测和治疗。oct纳米棒技术有望作为一种集成的、非侵入性的系统广泛应用于需要图像引导干预的医疗问题。

DESCRIPTION (provided by applicant): An integrated, minimally invasive approach will be developed toward the detection, diagnosis, and treatment of cells and tissues in diseased states, using emerging biomedical imaging methods (optical coherence tomography, or OCT) and novel contrast agents (functionalized gold nanorods). OCT is capable of cellular-resolution imaging in the near infrared (NIR) and has the potential to diagnose abnormal cells and tissues at an early stage of disease, given sufficient contrast. Anisotropic gold nanorods exhibit tunable plasmon responses and can be engineered for strong absorption or scattering at select NIR frequencies, thereby enhancing the sensitivity and scope of OCT and related technologies. New OCT methods will be developed based on the enhanced optical contrast of anisotropic nanorods in isolated or aggregate forms. Gold nanorods with strong and selective NIR extinction will be functionalized with biomolecular ligands for selective targeting of tissues with abnormal biomarker expression. These will serve as site-directed optical labels by binding to cell-surface markers or by cell uptake. Nanorods with magnetic tips may provide additional positional and orientational control within the tissue, and enhance the development of a novel, dynamic OCT method. Metal nanorods can also support extremely large absorption cross-sections and generate highly localized thermal gradients, and can be used to enhance optically-induced hyperthermia at low radiation power. The proposed nanorod-enhanced OCT imaging system will first be applied toward tissue phantoms, then toward the in vivo detection and treatment of tumor cells by local hyperthermia using a hamster cheek pouch model. The OCT-nanorod technology is anticipated to have broad application as an integrated, noninvasive system for medical concerns which require image-guided intervention.