Multifunctional nanoparticle-mediated imaging and therapeutic techniques are promising modalities for accurate localization and targeted treatment of cancer in clinical settings. Thermoacoustic (TA) imaging is highly sensitive to detect the distribution of water, ions or specific nanoprobes and provides excellent resolution, good contrast and superior tissue penetrability. TA therapy is a potential non-invasive approach for the treatment of deep-seated tumors. In this study, human serum albumin (HSA)-functionalized superparamagnetic iron oxide nanoparticle (HSA-SPIO) is used as a multifunctional nanoprobe with clinical application potential for MRI, TA imaging and treatment of tumor. In addition to be a MRI contrast agent for tumor localization, HSA-SPIO can absorb pulsed microwave energy and transform it into shockwave via the thermoelastic effect. Thereby, the reconstructed TA image by detecting TA signal is expected to be a sensitive and accurate representation of the HSA-SPIO accumulation in tumor. More importantly, owing to the selective retention of HSA-SPIO in tumor tissues and strong TA shockwave at the cellular level, HSA-SPIO induced TA effect under microwave-pulse radiation can be used to highly-efficiently kill cancer cells and inhibit tumor growth. Furthermore, ultra-short pulsed microwave with high excitation efficiency and deep penetrability in biological tissues makes TA therapy a highly-efficient anti-tumor modality on the versatile platform. Overall, HSA-SPIO mediated MRI and TA imaging would offer more comprehensive diagnostic information and enable dynamic visualization of nanoagents in the tumorous tissue thereby tumor-targeted therapy.

中文翻译：

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基于超顺磁性氧化铁纳米粒子的超短脉冲微波泵浦热弹性效应的热声成像和治疗指导

多功能纳米粒子介导的成像和治疗技术是在临床环境中准确定位和靶向治疗癌症的有前途的方式。热声（TA）成像对检测水，离子或特定纳米探针的分布非常敏感，并提供出色的分辨率，良好的对比度和出色的组织穿透性。TA疗法是用于治疗深部肿瘤的潜在的非侵入性方法。在这项研究中，人类血清白蛋白（HSA）功能化的超顺磁性氧化铁纳米颗粒（HSA-SPIO）被用作多功能纳米探针，具有在MRI，TA成像和治疗肿瘤中的临床应用潜力。除了是用于肿瘤定位的MRI造影剂之外，HSA-SPIO可以吸收脉冲微波能量，并通过热弹性效应将其转换为冲击波。因此，通过检测TA信号而重构的TA图像被期望是肿瘤中HSA-SPIO积累的灵敏且准确的表示。更重要的是，由于HSA-SPIO在肿瘤组织中的选择性保留和细胞水平的强TA冲击波，在微波脉冲辐射下HSA-SPIO诱导的TA效应可用于高效杀死癌细胞并抑制肿瘤生长。此外，在生物组织中具有高激发效率和深穿透性的超短脉冲微波使TA疗法成为多功能平台上的高效抗肿瘤手段。全面的，