新型含苯硼酸和萘双亲化合物的合成与囊泡荧光传感器的制备

合成了含有识别基团苯硼酸和荧光基团萘的新型对-(5-十二烷氧基-1-氧基)萘]甲基苯硼酸{p-(5-dodecyloxy-1-oxy) naphthalene] methyl-phenylboronic acid, DNMPBA}双亲化合物; 该化合物在THF/水选择性溶剂中自组织成囊泡, 囊泡的相变温度为56.8 ℃; 当向囊泡体系加糖时, DNMPBA囊泡中的萘生色基在345 nm的荧光峰强度急剧增强; 荧光强度随添加不同糖的变化趋势为果糖>葡萄糖>麦芽糖>乙二醇. 荧光强度增强可能归因于所形成的硼酸酯减弱了DNMPBA双亲化合物中一个氧原子孤对电子对萘生色基的猝灭作用而使荧光强度重新恢复. DNMPBA囊泡与糖的相互作用导致体系荧光强度变化, 使该体系有可能应用于检测生物物质如糖的化学传感器.

Synthesis of a Novel Amphiphile Containing Both Phenylboronic Acid and Naphthalene and Preparation of the Fluorescent Vesicular Sensor

A novel amphiphile containing two functional groups of both naphthalene and phenylboronic acid, p-(5-dodecyloxy-1-oxy) naphthalene] methyl-phenylboronic acid(DNMPBA), was synthesized. The amphiphile was self-organized into vesicles in the selective solution of THF/water(φ=0.6) buffered at pH=6.86. The Tc of the vesicles from crystal to liquid crystal is 56.8 ℃. Addition of saccharides to the vesicular solution, the fluorescent intensities of naphthalene in DNMPBA vesicles centered at 345 nm increase dramatically with increasing concentration of saccharides. The changed tendency for fluorescent intensities of the DNMPAB vesicles with saccharides is similar to the other systems reported in literature to favor the binding with fructose over glucose and maltose. The increase of fluorescence intensity is ascribed to boronic ester formation which might diminish the photoinduced electron transfer(PET) progress to induce fluorescence retrieval and, therefore, increase the fluorescence intensity. The vesicular sensor through the interactions between boronic acid and saccharides displayed at a biomimetic membrane interface can be detected by means of fluorescence intensities. The results suggest that the fluorescent vesicles might be used as biosensors to determine saccharides.