【作者】 程探宇；

【导师】 徐玉芳；

【作者基本信息】 华东理工大学 ， 药物化学， 2011， 博士

【摘要】 荧光分子探针能够将分子识别的信息转换成荧光信号,具有最高可达单分子检测的高灵敏度、能够实现开关操作、对亚微粒子具有可视的亚纳米空间分辨能力和亚毫秒时间分辨能力、原位检测(荧光成像技术)以及利用光纤进行远距离检测等众多优点。开关型信号变化能够降低自身荧光的干扰,从而极大地提高探针的灵敏度。氟硼吡咯(BODIPY)作为荧光发色团具有非常优越的特性：1、摩尔消光系数比较大；2、尖锐的紫外吸收和荧光发射峰；3、很高的荧光量子产率；4、对极性和PH的耐受性比较好,而且在生理环境下非常稳定。本文基于BODIPY荧光团,设计合成了五个荧光探针。所有探针结构都经1H NMR、13C NMR和HRMS等确认。利用紫外-可见光和荧光光谱法系统研究了荧光探针对目标物的识别性能及识别机理。1、将多酰胺链受体通过苯乙烯基共轭连接到BODIPY的3位,合成了Cd2+探针CSl。该探针在中性缓冲液中高选择、高灵敏识别镉离子,镉离子结合前后荧光强度增强了大约200倍,荧光量子产率增加了大约100倍。CSI可以裸眼和荧光双通道区分Cd2+和Zn2+。它还可以穿透细胞膜,用于细胞内的Cd2+成像。2、在BODIPY的3位和5位引入两个多酰胺链受体,合成了探针CS2。它可以在中性缓冲溶液中选择性地识别镉离子,在镉离子结合前后真正实现了从无到有OFF-ON地信号变化。探针CS2和镉离子的金属螯合物CS2-Cd在水溶液中可以高灵敏、高选择性地检测PPi。在PPi存在时,CS2-Cd的荧光强度会迅速地减弱,但是在同样条件下PPi类似物(ADP和ATP)没有引起任何荧光变化。3、在BODIPY的3位和5位引入不同的取代基,设计、合成了近红外探针HMS (λem=658 nm)。该荧光探针的选择性可以通过改变缓冲体系进行调控,在不同的缓冲液体系,HMS可以选择性识别Hg2+、Pb2+和Cd2+。4、合成了基于氟硼吡咯荧光团和肼活性基团的次氯酸根离子荧光探针HCS。该探针在中性条件下,随着C1O-的加入,HCS的吸收有着明显的波长变化,荧光急剧增加而且有明显的蓝移过程。更多还原

【Abstract】 Fluorescent probes can transfer molecular recognition events into fluorescence signals and then make a bridge between man and molecule. The advantages of molecular fluorescence for sensing can be summarized:high sensitivity of detection down to the single molecule, "on-off”switch ability, subnanometer spatial resolution and submillisecond temporal resolution, observation in situ, remote sensing by using optical fibres, etc. Off-On fluorescent probes have tremendous superiority. They have low autofluorescence and show good sensitivity.Boron dipyrromethene (BODIPY) as a fluorophore has tremendous superiority, such as big molar extinction coefficient, sharp absorption and fluorescence peaks, high fluorescence quantum yield and high stability. Herein five fluorescent probes based on BODIPY for ions were designed and synthesized. All compounds were characterized by 1HNMR,13C NMR and HRMS. Their photophysical properties and responses to cations were systematically investigated by means of UV-vis and fluorescence methods.1. Fluorescent probe (CS1) was designed and synthesized, whose receptor of polyamide was conjugated to 3-position of BODIPY through styryl. The probe could detect Cd2+ selectively and sensitively in neutral buffer solution. The fluorescent intensity enhanced about 200-fold and fluorescence quantum yield increased almost 100-fold after Cd2+addition. Moreover, its fluorescence intensity enhanced in a linear fashion with concentration of Cd2+ and thus can be potentially used for quantification of Cd2+. CS1 can readily distinguish Cd2+ from Zn2+by both naked eye and fluorescence, and the living cell image experiments further demonstrate its value in the practical applications of biological systems.2. Another fluorescent probe of CS2 for cadmium was synthesized through conjugating two polyamide receptors to 3-and 5-position of BODIPY. It is a selective off-on probe for Cd2+in aqueous solution. The complex CS2-Cd of CS2 with Cd2+showed good selectivity and sensitivity toward pyrophosphate (PPi). The fluorescent intensity of CS2-Cd decreased significantly with PPi addition, and it could distinguish PPi from ADP and ATP.3. NIR probe HMS (λem= 658nm) was designed and synthesized, which introduced two different substituent groups to 3-and 5-position of BODIPY. The selectivity of HMS toward Cd2+, Hg2+and Pb2+could be modulated via judicious choice of aqueous buffer solutions.4. A hypochlorite probe HCS based on BODIPY and hydrazinium was synthesized. When C10- was added, obvious absorption wavelength change was observed and the fluorescence decreased significantly with wavelength blue-shift.更多还原