Rankin C J, Fuller E N, Hamor K H, Gabarra S A, Shields T P
Department of Chemistry and Biochemistry, University of North Carolina-Greensboro, Greensboro, North Carolina 92110, USA.
Nucleosides Nucleotides Nucleic Acids. 2006;25(12):1407-24. doi: 10.1080/15257770600919084.
Theophylline is a potent bronchodilator with a narrow therapeutic index. A simple fluorescent biosensor that detects clinically relevant theophylline concentrations has been developed using the well-characterized theophylline binding RNA aptamer. Hybridization of the RNA aptamer to a fluorescently labeled DNA strand (FL-DNA) yields a fluorescent RNA:DNA hybrid that is sensitive to theophylline. The biosensor retains the remarkable selectivity of the RNA aptamer for theophylline over caffeine and is sensitive to 0-2 muM theophylline, well below the clinically relevant concentration (5-20 mg/L or approximately 10-50 muM). Adding a dabcyl quenching dye to the 3'-terminus of the fluorescently labeled DNA strand yielded a dual-labeled DNA strand (FL-DNA-Q) and increased the dynamic range of this simple biosensor from 1.5-fold to 4-fold.
茶碱是一种具有狭窄治疗指数的强效支气管扩张剂。利用特性明确的茶碱结合RNA适配体，开发出了一种能检测临床相关茶碱浓度的简单荧光生物传感器。RNA适配体与荧光标记的DNA链（FL-DNA）杂交，产生对茶碱敏感的荧光RNA:DNA杂交体。该生物传感器保留了RNA适配体对茶碱相对于咖啡因的显著选择性，并且对0 - 2 μM的茶碱敏感，远低于临床相关浓度（5 - 20 mg/L或约10 - 50 μM）。在荧光标记的DNA链的3'末端添加一种达可昔（dabcyl）淬灭染料，得到了一种双标记DNA链（FL-DNA-Q），并将这种简单生物传感器的动态范围从1.5倍提高到了4倍。
