A Plasmonic Mass Spectrometry Approach for Detection of Small Nutrients and Toxins

Abstract

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.Electronic supplementary materialThe online version of this article (10.1007/s40820-018-0204-6) contains supplementary material, which is available to authorized users.

Design of plasmonic nanomaterials for diagnostic spectrometry

“…13,26,27 The controllable size and shape of these particles can be tailored by optimization of synthetic conditions, such as stabilizing agents, 28,29 surface functionalization 15,30 and temperature variations. 24,29 Plasmonic nanomaterials are most commonly synthesized using chemical methods such as citrate/borohydride/ascorbic acid reduction, 14,30,31 hydrothermal reactions, 32 light-mediated processes, laser/g-ray/electron beam irradiation, and lithography. Nanomaterials prepared through physical methods involve the deposition of thin lms by condensing atomized elements or components by vapour evaporation or sputtering.…”

“…Therefore, Au 36 and Cu 38 nanoparticles (e.g., nanospheres, nanoshells, and nanorods) are more suitable for the visible and NIR laser, and Ag nanoparticles are more suitable for the UV laser due to the different frequencies where interband transitions occur. 14,24,47 Recently, we demonstrated that the anti-bonding modes of Au nanoshells can generate hot carriers in the UV range and consequently display superior sensitivity over traditional organic matrices for enhanced LDI MS-based detection and proling of small metabolites in serum samples. 48 SERS is another powerful spectroscopic technique providing ultrasensitive ngerprinting of target molecules up to the single molecule level.…”

“…In MALDI MS, matrix materials determine the LDI efficiency with identication of diverse molecules over a broad mass range. 6,14,24 In SERS, substrate materials enhance the Raman signals for ultrasensitive detection even at the single molecule level. 23,25 Notably, both MALDI MS and SERS require engineered nanomaterials with tuneable plasmonic properties, considering the key role of the interface between materials and light in both methods.…”

A coming era of precision diagnostics based on nano-assisted mass spectrometry

“…1,8,9 Among numerous analytical approaches for omics, mass spectrometry (MS) has become the major tool due to the desirable throughput, sensitivity, and identification capability. [10][11][12][13] To date, the state-of-art MS methods and techniques have advanced omics in all levels * Corresponding Authors: E-mail: jjwan@chem.ecnu.edu.cn, k.qian@sjtu.edu.cn including genomics, 14,15 proteomics, [16][17][18] and metabolomics. [19][20][21] Nowadays, interdisciplinary research is fundamental to achieve real case applications of MS in clinics.…”

Design of Hierarchical Beads for Efficient Label‐Free Cell Capture

“…Notably, the presence of nanosized S1 was critical for linkage/conjugation, considering the role of silica nanoparticles with strong adhesion as nanoglues . Compared to common hierarchical bi‐structures,1b,3b,5a,6b,14a,19 the above assembling design may lead to the development of tri‐structures of interest for hierarchical materials.…”