Key Laboratory of Photochemical Conversion and Optoelectronic Materials, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing, 100190, People's Republic of China.
Anal Chem. 2011 Sep 1;83(17):6559-64. doi: 10.1021/ac2008724. Epub 2011 Aug 15.
A ratiometric fluorescence sensor based on pyrene was designed for selective detection of heparin in HEPES (N-(2-hydroxyethyl)piperazine-N'-ethanesulfonic acid) buffer and serum sample. Pyrene and long-chain alkanes were linked through bisquaternary functionality in the sensor which could interact with heparin via supramolecular assembly. A ratiometric fluorescent signal change of the sensor can be observed because of the specific monomer-excimer conversion of pyrene which is modulated by the supramolecular self-assembly of sensor and heparin. Upon addition of heparin, the excimer emission of the sensor at 489 nm is observed and the monomer emission intensity at 395 nm decreases concomitantly. Addition of heparin derivatives with very similar structure such as chondroitin 4-sulfate or hyaluronic acid to the same sensor solution only leads to very smaller changes in intensity ratios probably because of lower charge density and more distant spatial distribution of anions (or disadvantageous spatial orientation of anions) as compared to those of heparin. The novel sensor can effectively differentiate heparin from its derivatives with relatively low background interference and wide linear response in HEPES and serum. A linear calibration curve is obtained from 0 to 3.4 μM for heparin quantification in serum.
基于芘的比率荧光传感器被设计用于在 HEPES（N-(2-羟乙基)哌嗪-N'-乙磺酸）缓冲液和血清样品中选择性检测肝素。传感器中通过双季铵官能度将芘与长链烷烃连接，通过超分子组装与肝素相互作用。由于芘的特定单体-二聚体转换被传感器和肝素的超分子自组装调制，可以观察到传感器的比率荧光信号变化。加入肝素后，可以观察到传感器在 489nm 处的二聚体发射，同时 395nm 处的单体发射强度相应降低。将具有非常相似结构的肝素衍生物（如硫酸软骨素 4-硫酸盐或透明质酸）添加到相同的传感器溶液中，仅导致强度比发生非常小的变化，这可能是由于与肝素相比，阴离子的电荷密度更低且空间分布更远（或阴离子的空间取向不利）。与肝素衍生物相比，新型传感器可以在 HEPES 和血清中有效地区分肝素，具有相对较低的背景干扰和较宽的线性响应。在血清中，从 0 到 3.4 μM 可以得到用于肝素定量的线性校准曲线。
