The precision oncology significantly relies on the development of multifunctional agents to integrate tumor targeting, imaging and therapeutics. In this study, a first small-molecule theranostic probe, RhoSSCy is constructed by conjugating 5′-carboxyrhodamines (Rho) and heptamethine cyanine IR765 (Cy) using a reducible disulfide linker and pH tunable amino-group to realize thiols/pH dual sensing. In vitro experiments verify that RhoSSCy is highly sensitive for quantitative analysis and imaging intracellular pH gradient and biothiols. Furthermore, RhoSSCy shows superb tumor targeted dual-modal imaging via near-infrared fluorescence (NIRF) and photoacoustic (PA). Importantly, RhoSSCy also induces strongly reactive oxygen species for tumor photodynamic therapy (PDT) with robust antitumor activity both in vitro and in vivo. Such versatile small-molecule theranostic probe may be promising for tumor targeted imaging and precision therapy.

中文翻译：

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用于肿瘤靶向成像和光动力疗法的双反应分子探针

精确肿瘤学极大地依赖于多功能药物的开发，以整合肿瘤靶向，影像学和治疗学。在这项研究中，第一个小分子治疗诊断探针RhoSSCy是通过使用可还原的二硫键和pH可调的氨基将5'-羧基若丹明胺（Rho）和七甲基花菁IR765（Cy）共轭构建的，从而实现硫醇/ pH双重传感。体外实验证明，RhoSSCy对定量分析以及对细胞内pH梯度和生物硫醇成像具有很高的敏感性。此外，RhoSSCy通过近红外荧光（NIRF）和光声（PA）显示了出色的肿瘤靶向双峰成像。重要的是，RhoSSCy还可以诱导具有强烈抗肿瘤活性的强光合活性氧，用于肿瘤光动力疗法（PDT）。体外和体内。这种多功能的小分子治疗诊断探针有望用于肿瘤靶向成像和精确治疗。