Detection and quantification of folic acid in serum via a dual-emission fluorescence nanoprobe

  • Yu He
  • Shuo Wang
  • Junping WangEmail author
Research Paper


Folic acid (FA) is an essential vitamin in humans, and thus, rapid, accurate, and sensitive methods for its quantification in different biological samples are needed. This work describes a novel, simple, and effective dual-emission fluorescence nanoprobe for FA detection and quantification. The probe was covalently linked to amino-modified orange quantum dots (QDs) and carboxyl-modified blue graphene quantum dots (GQDs). The resulting material exhibited two emission peaks at 401 and 605 nm upon excitation at 310 nm. The probe had good selectivity and sensitivity toward FA with an exceptionally low detection limit (LOD = 0.09 nM). This probe was effectively used to quantify FA in animal serum samples. The method has potential utility for FA analysis in different types of biological samples.

Graphical abstract


Fluorescence Dual-emission Quantum dots Folic acid Rabbit serum 



We thank LetPub ( for its linguistic assistance during the preparation of this manuscript.

Funding information

This work was supported by “The National Key R&D Program of China” (No. 2016YFD0401202) and the Special Project of Tianjin Innovation Platform (No. 17PTGCCX00230).

Compliance with ethical standards

Conflict of interest

The authors declare that they have no competing interests.


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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2019

Authors and Affiliations

  1. 1.State Key Laboratory of Food Nutrition and Safety, College of Biotechnology and Food EngineeringTianjin University of Science and TechnologyTianjinChina
  2. 2.Tianjin Key Laboratory of Food Science and Health, School of MedicineNankai UniversityTianjinChina

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