Development of Active Transport and Ion-Channel Sensors

构建了三种不同类型的传感器。(1)利用含有亲脂性大环多胺和环糊精多胺衍生物的Langmuir-Blodgett膜构建了一系列响应于有机和无机阴离子的离子通道型传感器，这些衍生物能够以多质子化形式与阴离子客体结合。该传感器显示出选择性响应（膜渗透性的调制，包括腺苷核苷酸，二羧酸和无机阴离子的客人阴离子的数量。(2)从大鼠脑突触膜分离谷氨酸受体通道蛋白，将其与双层类脂膜（BLM）复合，制成生物离子通道传感器。基于谷氨酸触发的单通道电流，获得了2.1x10^5的信号放大。(3)从豚鼠小肠刷状缘膜分离Na^+/D-葡萄糖共转运蛋白，将其组装到双层膜上，构建了主动转运型的D-葡萄糖BLM传感器。传感器的响应被测量为在恒定的外加电位下由共转运的Na^+离子通量引起的电导变化。传感器的响应由高于10 μ M的D-葡萄糖诱导<-9>，但不由相应的L-异构体、D-果糖和D-甘露糖诱导。

Three different types of sensors were constructed. (1) A series of ion-channel type sensors responsive to organic and inorganic anions were constructed utilizing Langmuir-Blodgett membranes containing lipophilic derivatives of macrocyclic polyamine and cyclodextrin polyamine, capable of binding with anionic guests in multiprotonated forms. The sensor showed selective response (modulation of membrane permeability to a number of guest anions including adenosine nucleotides, dicarboxylates and inorganic anions. (2) A biological ion-channel sensor was fabricated by incorporating glutamate receptorion-channel protein, isolated from synaptic membrane of rat brain, into a planar bilayer lipid membrane (BLM) . A signal amplification of 2.1x10^5 was obtained based on the glutamate-triggered single channel current. (3) A Na^+/D-glucose co-transporter protein, isolated from intestinal brush border membrane of guinea pigs, was incorporated into a bilayer membrane to construct an active transport type BLM sensor for D-glucose. The response of the sensor was measured as a conductance change arising from co-transported Na^+ ion flux under a constant applied potential. The response of the sensor was induced by D-glucose above 10^<-9> M, but not by the corresponding L-isomer, D-fructose and D-mannose.