pH响应型近红外菁类荧光探针的合成及细胞成像

癌症的早期诊治是提高癌症患者治愈率的关键。但传统的"always on"型显影剂存在自身背景干扰且易造成"假阳性"等问题。本文利用肿瘤细胞具有弱酸性这一特性,设计合成了p H激活型不对称菁类荧光探针,并选用氨基葡萄糖作为修饰基团以增强探针母体的水溶性并赋予其肿瘤靶向性。该探针具有p H调控的"off-on"可逆的近红外荧光特性,以及与肿瘤弱酸性微环境相吻合的p H响应范围。此外,探针的浓度高达1.0×10~(-5)mol/L时仍未表现出明显的细胞毒性。该探针在细胞水平实现了肿瘤细胞弱酸性微环境的特异性成像。

pH Responsive Near-infrared Cyanine Probe for Cell Imaging

Early diagnosis and treatment is crucial to increase the cure rate of cancer patients.However,conventional "always on" imaging agents often shows poor signal-to-noise ratio or even "false positive" results.Hence,the development of tumor-specific probes with sufficient specificity and sensitivity is necessary.Here,we report the design and preparation of a pH-activated asymmertric cyanine probe by taking the advantage of intrinsic weak acid of tumor microenvironment for cell imaging.To improve the hydrophily and to endow the tumor-targeting ability,we further functionalize the probe with glycosyl.The probe not only exhibits pH-mediated " off-on" reversibly NIR fluorescence,but also possesses suitable pH response range to tumor microenvironment.Moreover,the probe exhibits no signifcant cytotoxicity for the studied cells until the probe concentration up to 1.0 × 10-5 mol/L.The probe has successfully realized tumor-specific imaging in cells.