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、诊断和治疗患病状态下的细胞和组织。OCT能够在近红外（NIR）中进行细胞分辨率成像，并且如果有足够的对比度，则有可能在疾病的早期阶段诊断异常细胞和组织。各向异性金纳米棒表现出可调谐的等离子体响应，并且可以被设计用于在选定的NIR频率下的强吸收或散射，从而增强OCT和相关技术的灵敏度和范围。 新的OCT方法将基于孤立或聚集形式的各向异性纳米棒的增强光学对比度来开发。具有强的和选择性的NIR消光的金纳米棒将用生物分子配体官能化，用于选择性靶向具有异常生物标志物表达的组织。这些将通过与细胞表面标记物结合或通过细胞摄取而用作定点光学标记。具有磁性尖端的纳米棒可以在组织内提供额外的位置和取向控制，并增强新型动态OCT方法的开发。 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，并且可以用于在低辐射功率下增强光诱导的热疗。所提出的纳米棒增强OCT成像系统将首先应用于组织幻影，然后应用于使用仓鼠颊囊模型通过局部高温对肿瘤细胞进行体内检测和治疗。OCT纳米棒技术有望作为一种集成的非侵入性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.