Graphene quantum dots (GQDs), which have high photostability, anti-photobleaching and scintillation, good biocompatibility and low toxicity, are important member of the fluorescent material family, and have attracted extensive research interest. In this paper, a fluorescence resonance energy transfer (FRET) biosensor based on protoporphyrin IX (PpIX) and GQDs was developed for melamine detection. PpIX was bound to the surface of GQDs to produce self-assembled nanosensors, and a FRET process occurred between GQDs and PpIX. However, due to the combination of melamine and PpIX, the FRET process was shut down in the presence of melamine. The FRET system could quickly and accurately detect melamine with a detection range of 1.0 × 10⁻⁸ to 2.0 × 10⁻⁶ mol/L based on the fluorescence intensity ratio of PpIX and GQDs, and the detection limit was 3.6 × 10⁻⁹ mol/L. This method obtained satisfactory results when it was employed to the determination of melamine in milk samples.

具有高的光稳定性，抗光漂白和闪烁性，良好的生物相容性和低毒性的石墨烯量子点（GQD）是荧光材料家族的重要成员，并引起了广泛的研究兴趣。本文开发了一种基于原卟啉IX（PpIX）和GQDs的荧光共振能量转移（FRET）生物传感器用于三聚氰胺检测。PpIX被绑定到GQD的表面以产生自组装的纳米传感器，并且在GQD和PpIX之间发生了FRET过程。但是，由于三聚氰胺和PpIX的结合，FRET工艺在三聚氰胺存在下被关闭。FRET系统可以快速，准确地检测三聚氰胺，检测范围为1.0×10 ^-8至2.0×10 ^-6 PpIX和GQDs的荧光强度比为mol / L，检出限为3.6×10 ^-9  mol / L。该方法用于牛奶样品中三聚氰胺的测定，结果令人满意。