用于非胁迫状态细胞中低浓度活性氧自由基检测的聚合物放大型荧光探针的设计与制备

A new type of fluorescent probes for reactive oxygen species (ROS) were prepared combing the signal amplification properties of fluorescent conjugated polymers and the selective recognition ability of functional groups, and applied to detection of ROS in cell under non-coercive state. The widely used fluorescent conjugated polymer including poly(thiophene) (PT), poly(p-phenylenevinylene) (PPV), poly(p-phenyleneethynylene) (PPE) or poly(fluorine-co-phenylene) (PFP) were chosen as the light-emitting unit, and the recognition unit was selected according to the small molecule probe designed by our research group. Based on the side chain modification for the fluorescent conjugated polymers, novel polymer fluorescent probe was prepared combining the specific recognition unit for the ROS and the merit of fluorescent conjugated polymer. The method combined the signal amplification properties of fluorescent conjugated polymers and merit of the molecular fluorescent probe, the charge and energy produced by interaction between the recognition unit and the ROS can be transfer effectively along the polymer chain, thus the detection sensitivity can be effectively improve through the a few times amplification effect. The subject is expected to achieve ROS detection with high selectivity and high sensitivity in cells under non-coercive state, which has important theoretical and application value for the ROS detection.

利用荧光共轭聚合物的信号放大特性，选择对活性氧分子有特异性的识别基团，制备对活性氧自由基具有特异性识别性能的高灵敏性的新型荧光探针，并将其用于细胞中活性自由基的检测。首先选择目前研究较多的聚噻吩类(PT)、聚对苯撑乙烯类( PPV)、聚对苯撑乙炔类(PPE)及聚苯撑芴类(PFP)等荧光共轭聚合物作为发光单元，以荧光共轭聚合物合成及侧链修饰为基础，将本课题组设计合成的一系列活性氧自由基特异性识别基团修饰到聚合物上，制备新型的聚合物的荧光探针。该制备方法融合了荧光共轭聚合物的信号放大作用和分子荧光探针的优点，可将分子探针与活性氧自由基相互作用过程中产生的电荷和能量沿共轭分子链进行有效传递, 成几十倍放大作用, 从而有效提高自由基检测灵敏度。本课题有望实现细胞中活性氧自由基的高选择性、高灵敏性的检测，具有重要的理论意义和实际应用价值。

以细胞内的活性分子为研究对象，发展了几种新型的荧光探针，成功的用于细胞内活性小分子的成像分析。以聚芴为荧光团，制备了唾液酸印迹纳米材料，利用该材料具有双光子性质，有效的降低了样品背景荧光的干扰，成功的用于细胞及活体中唾液酸的成像研究。发展了基于四苯乙烯对硫化氢快速响应的荧光探针。合成了一种对过氧化氢快速响应的荧光探针，成功地将其应用于活细胞内过氧化氢水平研究。选用芴酮为荧光基团，有机硒为识别基团，通过硒键的氧化还原特性，实现了对细胞中次氯酸的可逆识别。利用硼酸为识别位点，结合分子印迹技术的空间识别特性，发展了温敏型的印迹材料，成功应用于实际样品中目标糖蛋白的测定，取得了令人满意的结果。总之，该项目发展了几种细胞内活性小分子的检测方法，为细胞内活性分子相关疾病标志物的检测提供了荧光分析工具。