Chemistry Department, Faculty of Science, Al-Azhar University, P.O.11884, Nasr City, Cairo, Egypt.
Dyeing, Printing and Textile Auxiliaries Department, Textile Research Division, National Research Centre, 33 El Bohouth st, Dokki, P.O.12622, Giza, Egypt.
J Fluoresc. 2020 May;30(3):601-612. doi: 10.1007/s10895-020-02522-1. Epub 2020 Apr 13.
A new turn on fluorescence probe based on 3',6'-dihydroxy-6-methyl-2-((pyridin-2-ylmethylene)amino)-4-(p-tolyl)spiro[benzo[f]isoindole-1,9'-xanthen]-3(2H)-one (BFFPH) derived from benzo[f]fluorescein was prepared. Full characterization of the prepared probe using spectroscopic analysis was described such as IR, NMR and MS spectra. The sensitivity of BFFPH for monitoring of pH change in alkaline medium was studied. BFFPH exhibited a high sensitivity to alkaline pH by two pKa values at 8.82 and 10.66 in UV/vis spectroscopy titration. The pH monitoring was studied in broad range of pH values (2.5-12.2) at two pKa values at 8.72 and 10.73 by recording the effect of pH on the fluorescence intensity of BFFPH. The acid-base reversibility character of the probe was investigated as well as the effect of the pH change on the fluorescence quantum yield. The application of the prepared BFFPH probe for detection of living Escherichia coli (E. coli) bacteria using confocal fluorescence microscope was investigated.
一种基于 3'，6'-二羟基-6-甲基-2-((吡啶-2-亚甲基)氨基)-4-(对甲苯基)螺[苯并[f]异吲哚-1,9'-氧杂蒽]-3(2H)-酮（BFFPH）的荧光探针的新应用，BFFPH 来源于苯并[f]荧光素。使用光谱分析对制备的探针进行了全面的表征，如红外光谱、核磁共振和质谱谱图。研究了 BFFPH 在碱性介质中监测 pH 值变化的灵敏度。BFFPH 在紫外/可见光谱滴定中在 8.82 和 10.66 处具有两个 pKa 值，对碱性 pH 具有高灵敏度。通过记录 pH 值对 BFFPH 荧光强度的影响，在两个 pKa 值 8.72 和 10.73 下研究了 BFFPH 在宽 pH 值范围（2.5-12.2）内的 pH 监测。研究了探针的酸碱可逆性特征以及 pH 值变化对荧光量子产率的影响。还研究了用共聚焦荧光显微镜检测活大肠杆菌（E. coli）的制备的 BFFPH 探针的应用。
