Shu Wu^1, †, Linxi Qian^2, †, Lin Huang¹, Xuming Sun¹, Haiyang Su¹, Deepanjali D Gurav¹, Mawei Jiang², Wei Cai^2,*, Kun Qian^1,*

Nano-Micro Lett. (2018) 10: 52

First Online: 17 April 2018 (Article)

DOI:10.1007/s40820-018-0204-6

Nutriology relies on advanced analytical tools to study the molecular compositions of food and provide key information on sample quality/safety. Small nutrients detection is challenging due to the high diversity and broad dynamic range of molecules in food samples, and a further issue is to track low abundance toxins. Herein, we developed a novel plasmonic matrix assisted laser desorption/ionization mass spectrometry (MALDI MS) approach to detect small nutrients and toxins in complex biological emulsion samples. Silver nanoshells (SiO₂@Ag) with optimized structures were used as matrices and achieved direct analysis of ~6 nL of human breast milk without any enrichment or separation. We performed identification and quantitation of small nutrients and toxins with limit-of-detection down to 0.4 pmol (for melamine) and reaction time shortened to minutes, which is superior to the conventional biochemical method currently in use. The developed-approach contributes to the near-future application of MALDI MS in a broad field and personalized design of plasmonic materials for real case bio-analysis.

Keywords

Plasmonic materials; Laser desorption/ionization; Mass spectrometry; Small nutrients; Toxins