Abstract

A novel and sensitive turn-on fluorescent biosensor for herring sperm DNA (hsDNA) detecting was designed based on hsDNA-induced fluorescence enhancement of Sm3+-modulated glutathione (GSH)-capped CdTe quantum dots (QDs). The fluorescent biosensor was based on the following two properties. First, the high fluorescence of GSH-capped CdTe QDs could be effectively quenched by Sm3+ due to the binding of Sm3+ to the GSH on the surface of the QDs and the electron transfer from the photoexcited GSH-capped CdTe QDs to Sm3+. Second, the high affinity of hsDNA to Sm3+ enabled Sm3+ to be dissociated from the surface of GSH-capped CdTe QDs to form more stable complex with hsDNA in aqueous solution, thereby enhancing the fluorescence of Sm3+-modulated GSH-capped CdTe QDs. Experimental results showed that the enhanced fluorescence intensity of Sm3+-modulated GSH-capped CdTe QDs was directly proportional to the concentration of hsDNA in the range from 0.012 to 14.0μgmL−1 with a good correlation coefficient of 0.9977, and the detection limit (3σ/S) was 3.61ngmL−1. To further investigate perfect analysis performance, the developed biosensor was applied to the determination of hsDNA in synthetic samples and human fresh serum samples with satisfactory results.

Full Text
Published version (Free)

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call