A robust and versatile signal-on fluorescence sensing strategy based on SYBR Green I dye and graphene oxide

Huazhang Qiu,^1,* Namei Wu,^1,* Yanjie Zheng,¹ Min Chen,² Shaohuang Weng,¹ Yuanzhong Chen,³ Xinhua Lin<sup>1

1</sup>Department of Pharmaceutical Analysis, Faculty of Pharmacy, Fujian Medical University, Fuzhou, People’s Republic of China; ²Department of Orthopedic Surgery, Affiliated Union Hospital of Fujian Medical University, Fuzhou, People’s Republic of China; ³Fujian Institute of Hematology, The Affiliated Union Hospital of Fujian Medical University, Fuzhou, People’s Republic of China

*These authors contributed equally to this work

Abstract: A robust and versatile signal-on fluorescence sensing strategy was developed to provide label-free detection of various target analytes. The strategy used SYBR Green I dye and graphene oxide as signal reporter and signal-to-background ratio enhancer, respectively. Multidrug resistance protein 1 (MDR1) gene and mercury ion (Hg²⁺) were selected as target analytes to investigate the generality of the method. The linear relationship and specificity of the detections showed that the sensitive and selective analyses of target analytes could be achieved by the proposed strategy with low detection limits of 0.5 and 2.2 nM for MDR1 gene and Hg²⁺, respectively. Moreover, the strategy was used to detect real samples. Analytical results of MDR1 gene in the serum indicated that the developed method is a promising alternative approach for real applications in complex systems. Furthermore, the recovery of the proposed method for Hg2+ detection was acceptable. Thus, the developed label-free signal-on fluorescence sensing strategy exhibited excellent universality, sensitivity, and handling convenience.

Keywords: fluorescence, turn-on, SYBR Green I, graphene oxide, multidrug resistance protein 1 gene, Hg²⁺