Jump to main content
Jump to site search


Exploring Tunable Excitation of QDs to Maximize the Overlap with Absorber for Inner Filter Effect-based Phosphorescent Sensing of Alkaline Phosphatase

Abstract

Inner filter effect (IFE) is an effective way for fluorescence modulation and thus has been extensively explored for the development of fluorescent assays. Theoretically, the key to maximize the sensitivity of IFE-based fluorescent assays is to enlarge the overlap between the absorption of the absorber and the excitation/emission of the fluorophore. Therefore, in this work, the tunable excitation of quantum dots (QDs) was explored for screening of the IFE pair bearing the best IFE-based assay sensitivity. A series of QDs, including CdTe QDs with different sizes, carbon dots, Cu-doped CdS QDs, and Mn-doped ZnS QDs, were investigated. PNPP (p-nitrophenylphosphate) was chosen as the absorber since its absorption overlapped with the above QDs. Besides, it can be catalytically converted to p-nitrophenol (PNP) by alkaline phosphatase (ALP) together with absorption spectrum change (red-shift). Interestingly, it was found that the IFE efficiency of varied PNPP-QDs pairs increased almost linearly with the corresponding spectra overlap, and Mn-doped ZnS QDs was eventually chosen for IFE assay of ALP because of maximum spectra overlap and thus best sensitivity. A simple and sensitive turn-on phosphorescent ALP assay was developed, with a detection limit of 4  10-4 U/L. Because of the high sensitivity, we also found ALP of different origins possessed different enzymatic activity. The developed ALP phosphorescent assay was successfully employed for analysis of ALP in serum samples.

Back to tab navigation

Supplementary files

Publication details

The article was received on 23 May 2017, accepted on 14 Sep 2017 and first published on 14 Sep 2017


Article type: Paper
DOI: 10.1039/C7NR03673F
Citation: Nanoscale, 2017, Accepted Manuscript
  •   Request permissions

    Exploring Tunable Excitation of QDs to Maximize the Overlap with Absorber for Inner Filter Effect-based Phosphorescent Sensing of Alkaline Phosphatase

    J. Zhang, X. Lu, Y. Lei, X. Hou and P. Wu, Nanoscale, 2017, Accepted Manuscript , DOI: 10.1039/C7NR03673F

Search articles by author

Spotlight

Advertisements