Nanoparticle-immersed paper imprinting mass spectrometry imaging reveals uptake and translocation mechanism of pesticides in plants

Abstract

Design and discovery of carrier-mediated modified pesticides are vital for reducing pesticide dosage and increasing utilization, yet it remains a great challenge due to limited insights into plant translocation mechanisms. Nanostructure/nanoparticle assisted laser desorption/ionization strategy has established itself as a preferential analytical tool for biological tissue analysis, whereas potential applications in plant sciences are hindered with regard to the inability to slice plant leaves and petals. Herein, we report gold nanoparticle (AuNP)-immersed paper imprinting mass spectrometry imaging (MSI) for the spatiotemporal visualization of pesticide translocation in plant leaves. This approach plays a dual role in preserving spatial information and improving ionization efficiency for pesticides regardless of imaging artifacts due to homogenous AuNP deposition. Using this MSI platform, we proposed the elaborate plant translocation mechanism of agrochemicals for the first time, which is currently poorly understood. The dynamic processes of carrier-mediated pesticides can be clearly visualized, including crossing of plasma membranes by transporters, translocation downward in stems through the phloem, diffusion to the xylem and, conversely, accumulation at margins of the treated leaves. Moreover, this AuNP-assisted paper imprinting method could be highly compatible with laser-based MSI instruments, expediting researches across a broad range of fields, especially in nanomaterial development and life sciences.

Spatiotemporal Visualization of Insecticides and Fungicides within Fruits and Vegetables Using Gold Nanoparticle-Immersed Paper Imprinting Mass Spectrometry Imaging

“…A built in-house reflection time-of-flight mass spectrometer was built as reported earlier, with a few modifications (see Figure S1 in the Supplementary Materials ) [ 12 , 35 ]. Briefly, a 355 nm laser with a 5 ns pulse duration and a 10 Hz repetition rate (Minilite II, Continuum Inc., West Newton, MA, USA) was adopted in this study.…”

“…The output signals from the oscilloscope were processed using a self-compiled program written in LabVIEW (National Instruments, Austin, TX, USA). Ultimately, the mass spectra were obtained by Origin 9 software (OriginLab, Northampton, MA, USA), and MS images derived from ions of interest were obtained by Surfer 9 software (Golden Software, Inc., Golden, CO, USA) [ 21 , 35 , 40 ].…”

“…Despite the successful application of these imprinting materials in food imaging, they still suffer from several problems when integrated with laser-based MSI analysis, such as a low laser absorption efficiency and surface charge accumulation. Recently, we developed gold nanoparticle (AuNP)-immersed paper as an imprinting material coupled to a built in-house LDI-TOFMS platform, revealing the uptake and translocation mechanisms of carrier-mediated pesticides in plants [ 35 ]. However, the general applicability and the potential of this AuNP-immersed paper imprinting strategy for fruit and vegetable imaging has not yet been explored.…”

Mass spectrometry imaging for direct visualization of components in plants tissues

“…However, the low spatial resolution of imprinting is still a problem to be solved. Recently, Wu et al [35] reported a method of Au nanoparticle (AuNP)immersed paper imprinting combined with LDI-MSI to realize spatiotemporal visualization of pesticide transportation on leaves. AuNP-embedded paper serves as both imprinting and matrix, thus increasing the desorption efficiency of analytes.…”

Study on the Absorption and Conduction Properties of Vanisulfane in Tobacco

“…The results showed that the modified chlorantraniliprole was applied after foliar application. It has two-way conductivity in cabbage plants, and when the concentration of chlorantraniliprole in the phloem is too high, it can be transmitted to the xylem and then migrate to the leaves through the xylem [26].…”