CAJ | 학술논문

阴离子普遍存在于生命体和环境中，在化学、生物学、医学和环境领域都具有重要的作用，而硝酸根是其中一种非常重要的无机阴离子，对环境和人体健康都具有极大危害。目前测定硝酸根离子的方法主要有电化学法、离子色谱法和离子选择性电极法等。虽然各方法各具优势，但也存在明显不足。电化学法重现性差，而离子色谱法和离子选择性电极法需要较为复杂、昂贵的仪器及较长的分析时间。荧光光谱由于具有较高的灵敏度和操作简便等优点，近年来成为阴离子识别和检测领域的研究热点。以吡喃盐为起始原料，设计合成了一种新型的双吡啶盐化合物，通过核磁共振1 H谱、13 C谱以及高分辨质谱确定了其分子结构。并研究了其与不同阴离子的荧光识别性能，显示出对硝酸根离子明显的特异性识别。在双吡啶盐溶液中滴加硝酸根离子后，荧光呈现显著增强，而其他竞争性阴离子则淬灭初始荧光。通过荧光滴定实验证实双吡啶盐探针与硝酸根离子形成稳定的1∶1超分子配合物，稳定常数lg K＝5±0.02。通过计算机模拟计算以及变温核磁共振波谱表明硝酸根离子与双吡啶盐上活性氢形成稳定的氢键，并诱导整个双吡啶盐分子的共平面性增大，荧光强度增强，从而达到选择性识别的效果。
음리자보편존재우생명체화배경중，재화학、생물학、의학화배경영역도구유중요적작용，이초산근시기중일충비상중요적무궤음리자，대배경화인체건강도구유겁대위해。목전측정초산근리자적방법주요유전화학법、리자색보법화리자선택성전겁법등。수연각방법각구우세，단야존재명현불족。전화학법중현성차，이리자색보법화리자선택성전겁법수요교위복잡、앙귀적의기급교장적분석시간。형광광보유우구유교고적령민도화조작간편등우점，근년래성위음리자식별화검측영역적연구열점。이필남염위기시원료，설계합성료일충신형적쌍필정염화합물，통과핵자공진1 H보、13 C보이급고분변질보학정료기분자결구。병연구료기여불동음리자적형광식별성능，현시출대초산근리자명현적특이성식별。재쌍필정염용액중적가초산근리자후，형광정현현저증강，이기타경쟁성음리자칙쉬멸초시형광。통과형광적정실험증실쌍필정염탐침여초산근리자형성은정적1∶1초분자배합물，은정상수lg K＝5±0.02。통과계산궤모의계산이급변온핵자공진파보표명초산근리자여쌍필정염상활성경형성은정적경건，병유도정개쌍필정염분자적공평면성증대，형광강도증강，종이체도선택성식별적효과。
Anions are ubiquitously distributed not only in biological systems but also in environment .Accordingly ,anion recog‐nition and sensing have attracted increasing attention due to the important roles anion plays in biological ,chemical and environ‐mental fields .Among various anionic species ,NO3- is a very important inorganic anions which has a great harm to the environ‐ment and human health .At present ,methods for the determination of NO3- mainly contained electrochemical method ,ion chro‐matography and ion selective electrode method .Although all methods have their own advantages ,but also has the obvious defi‐ciency .Such as ,the reproducibility of electrochemical method is not good ,and ion chromatography and ion selective electrode method usually require expensive apparatus and lengthy analytical time .As a contrast ,fluorescence spectroscopy become a hot research topic in anion recognition and detection because of its high sensitivity and easy operation and other advantages in recent years .New bipyridinium salt L was designed and synthesized using pyrylium as a starting material .The molecular structure was determined by 1 H NMR ,13C NMR ,and high resolution mass spectrometry .The molecular recognition properties of L have been investigated through fluorescence titration experiments .The results indicate that L has sensitive and selective fluorescent re‐sponse to NO3- among other different anions .Significant enhancements in the fluorescence intensity of L were observed when va‐rious concentrations of NO3- were added ,while other competing anions have a quenching effect towards the initial fluorescence of solution .The fluorescence titration spectra shows that the bonding stoichiometry between receptor L and NO 3- is 1∶1 as a su‐pramolecular complexes (lg K=5 ± 0.02) .The chemosensing properties of L were evaluated through quantum chemical calcula‐tions and the variable temperature 1 H NMR titration .These results suggested that L has strong binding affinity towards NO3-with high selectivity ,which may be ascribed to the specific hydrogen bonding between the L and active H atom of the bipyrydini‐um salts .The interaction between L and NO3- made the complex more planar compared with L giving rise to enhanced fluores‐cence and specific selectivity towards NO 3- .