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Published on: July 14, 2017
Highly selective detection of spermine in human urine via a nanometal surface energy transfer platform
Dan Yuan1, Jia Jun Liu1, Hong Zhi Zhang1
1Key Laboratory on Luminescence and Real-Time Analytical Chemistry (Southwest University), Ministry of Education, College of Pharmaceutical Sciences, Southwest University, Chongqing 400715, China.
Abstract:
As an important biomarker of malignant tumors, spermine is closely related with some diseases. In this work, a nanometal surface energy transfer (NSET) strategy via the positively charged gold nanorods (AuNRs) and the negatively charged tetrakis (4-sulfonatophenyl) porphyrin (TPPS4) was developed to detect spermine in human urine. Under acidic condition, spermine possessed multi-cationic property and a strong affinity towards the anionic phosphate backbone of calf thymus DNA (ctDNA) by electrostatic attraction as well as the groove binding, which enabled to regulate the process of NSET between AuNRs and TPPS4, leading to the fluorescence quenching of TPPS4. Moreover, the quenched fluorescence was proportional to the concentration of spermine, which was applicable to monitor the level of spermine in human urine in the concentration range of 0.5-7.5 μM. The NSET platform for spemine is simple, selective and time-saving, which has great significance in early cancer diagnosis.
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