| Quantum dots(QDs), especially the metal ions doped quantum dots, possess specific advantages over organic fluorophores such as great photoluminescence efficiency, size-dependent emission wavelength, sharp emission and broad excitation profiles. As a novel nano functional material, QDs possess favorable optical performance of fluorescence and phosphorescence. Based on the favorable anti-interference performance, phosphorescent QDs have become one of the most important room temperature phosphorescence(RTP) probes for a series of analytes including medicines, biomacromolecules, metal ions, and small molecules in biological fluids. Due to slight changes in the physical properties or surface chemistry of quantum dots will change their optical characteristics, the quantum dots have unique advantages in sensitivity analysis. In this work, a simple RTP method was first proposed to detect adriamycin in biological fluids, which uses a functional material of Mn doped Zn S quantum dots(Mn:Zn S QDs) composited with poly(diallyldimethylammonium chloride)(PDDA). The proposed way is a cost-effective, rapid and sensitive method for the pharmaceutical analysis and possesses favorable anti-interference performance. The results show that the RTP method based on Mn:Zn S QDs or PDDA/Mn:Zn S QDs nanoassemblies is a promising optical probe for application analysis and provide a novel way for RTP sensor design and pharmaceutical analysis application.The main contents and results are as follows:(1) L-Cys to as the stabilizer, Mn doped Zn S quantum dots was synthesized in aqueous solution in a representative way. At the same time, the Mn:Zn S QDs were characterized by X ray powder diffractometry and transmission electron microscopy. The results show that this QDs synthesized with spherical, uniform size, and the diameter of about 4.5nm, and the optical performance of QDs is favorable. Mn:Zn S QDs with excitation wavelength of 316 nm and the emission wavelength was 585 nm.(2) Based on the PTP properties of L-Cys capped Mn:Zn S QDs, a rapid, simple method for detection ADM in aqueous solution and metabolic fluids of A549 was designed. With the addition of ADM, the RTP intensity of QDs was gradually quenched in PBS buffer medium. There was a good linear relationship between the ADM concentration and the change of RTP intensity, the linear range was 1.0-20.0?M with a correlation coefficient of 0.9932(R2). Meanwhile, the method was employed to monitor the time-dependent concentration of ADM in the metabolic fluids of A549 over 24 h and the results of this work was consistent with the previous report of metabolic analysis of ADM in the A549. In addition, under the optimum experimental condition, the RTP signal were unaffected by the selected interferences including metal ions, glucose and amino acids. More importantly, the Mn-Zn S QDs-based RTP method was selected in this research can effectively avoid the interference of scattering light of the matrix and nonspecific fluorescence.(3) Based on the theory of electronic interaction, PDDA/Mn:Zn S QDs nanoassemblies were easily synthesized by self-assembly way. The results show that the RTP intensity of QDs was highly enhanced and the detection ability for ADM was also improved. At the same time, the phosphorescence of Mn-Zn S QDs/PDDA nanoassemblies was highly quenched by ADM in p H 7.4 phosphate buffer solution. The linear calibration plot of the quenched room-temperature phosphorescence intensity against the concentration of ADM was examined in the range of 0.5~64.0 ?M with a correlation coefficient of 0.9932(R2), and the limit of detection for ADM was 0.45 ?M. According to the spectra of UV absorption, Zeta-potential and phosphorescence spectra, the possible quench mechanism by ADM were discussed. Meanwhile, the method was successfully applied to detection ADM in human serum samples, the average recovery rate was 98.3-101.1%. |
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