中文摘要：

荧光分析以灵敏度高，可采集信号丰富以及使用方便等优点备受人们关注，近年来已得到了迅速发展．但荧光分析的荧光强度除了受检测底物的影响外，还可能同时受到激发光强度的波动、传感器位置的移动等诸多因素的干扰，从而在一定程度上影响着荧光分析的准确度．

英文摘要：

In this paper we described the construction of a novel dual fluorescent film sensor using fluorescent dye Acridine Orange（AO） as an internal standard and CdTe as a fluorescent probe. Poly-sodium-4-styrenesul fonate（PSS） and Chitosan （CS） were respectively assembled between AO and CdTe. The constructed self-assembly muhilayers, Quartz/APES/PSS/AO/PSS/CS/CdTe, emits dual fluorescence at 600 and 530 nm, respectively. AO is shielded effectively by the assembled PSS and CS and thus its fluorescent intensity I1 doesn＇t change with the variation of the analyte concentration, thereby acting as an internal standard to provide reference signal. The ratio of dual fluorescence intensities of the thus constructed film sensor is not affected by the variations of the external environment factors such as excitation intensity and sensor position in the cell holder. A good linear relationship was found between dual fluorescence intensity ratio and DNA concentration over 0--250 ng/L. Quartz/APES/PSS/AO/PSS/CS/CdTe film is capable of an extremely highly sensitive detection for DNA with a detection limit of 6.6 ng/L. The analysis based on dual fluorescent self-assembled multilayers bearing a fluorescent internal standard would greatly improve the detection accuracy.