Construction of Molecule Sensing Systems and Evaluation of Their Abilities

迄今为止，我们已经开发出荧光环糊精作为检测水溶液中有机物质的化学传感器。在这些情况下，附在环糊精（CD）上的荧光部分在客人住宿时被排除在腔内。本研究的目的是制备含荧光CDs的固体器件，使其在工业上得到应用。我们使用纤维素和玻璃作为固体基质。作为荧光CDs，我们制备了一种新型荧光CDs (DnsGlu-β-CD)，该荧光CDs具有丹酰连接谷氨酸的游离羧基，可与底物的氨基反应。我们还制备了另一种荧光CD (DnsC4-β-CD)，该荧光CD由丹酰甘氨酸和1,4-二氨基丁烷修饰的β-CD反应制备，并将其固定在纤维素上。用NaIO_4处理纤维素，在NaCNBH_3存在下与1,6-二氨基己烷反应。DnsGlu-β-CD的羧基与改性纤维素的氨基缩合得到DnsGlu-β-CD固定化纤维素。另一方面，在NaCNBH_3存在下，DnsC4-β-CD与naio_4处理过的纤维素醛基反应，得到DnsC4-β-CD固定化纤维素。在水中添加客体后，DnsGlu-β- cd -和DnsC4-β- cd -固定纤维素膜的荧光强度均降低，表明制备了分子响应荧光纸。另一方面，我们用3-氨基丙基甲氧基硅烷处理玻璃，在玻璃表面引入氨基。DnsGlu-β-CD的羧基与氨基之间的缩合形成了DnsGlu-β-CD固定玻璃，但没有观察到客体诱导的荧光变化，这可能是由于玻璃表面吸附了丹酚部分。我们正在研究克服这个困难的方法。

Heretofore, we have developed fluorescent cyclodextrins as chemosensors for detecting organic species in aqueous solution. In those cases, the fluorescent moiety attached to cyclodextrin (CD) is excluded from the cavity upon guest accommodation. The object of this study is to produce solid devices containing the fluorescent CDs for application so that they may be used in industry. We used cellulose and glass as solid substrates. As fluorescent CDs, we prepared a novel fluorescent CD (DnsGlu-β-CD), which has dansyl attached glutamic acid bearing free carboxyl group to be reacted with amino group of the substrates. We also prepared another fluorescent CD (DnsC4-β-CD), which was prepared by the reaction between dansylglycine and 1,4-diaminobutane-modified β-CD to be immobilized to cellulose. Cellulose was treated with NaIO_4 and then reacted with 1,6-diaminohexane in the presence of NaCNBH_3. Condensation between carboxyl group of DnsGlu-β-CD and amino group of the modified cellulose gave DnsGlu-β-CD-immobilized cellulose. On the other hand, DnsC4-β-CD was reacted with aldehyde groups of NaIO_4-treated cellulose in the presence of NaCNBH_3 to give DnsC4-β-CD-immobilized cellulose. Both DnsGlu-β-CD- and DnsC4-β-CD-immobilized cellulose membranes decreased the fluorescence intensity upon guest addition in water, indicating that molecule responsive fluorescent papers were produced. On the other hand, we treated glass with 3-aminopropyltorimethoxysilane to introduce amino groups on the surface of the glass. The condensation between the carboxyl group of DnsGlu-β-CD and amino groups of the glass gave DnsGlu-β-CD-immobilized glass, but no guest-induced fluorescence change was observed probably due to adsorption of the dansyl moiety on the surface of the glass. We are exploring the method to overcome this difficulty.