Direct Imaging Mass Spectrometry of Plant Leaves Using Surface-assisted Laser Desorption/Ionization with Sputter deposited Platinum Film

作者：Ozawa Tomoyuki; Osaka Issey; Hamada Satoshi; Murakami Tatsuya; Miyazato Akio; Kawasaki Hideya; Arakawa Ryuichi

来源：Analytical Sciences, 2016, 32(5): 587-591.

DOI：10.2116/analsci.32.587

• Pt film
• imaging mass spectrometry (IMS)
• surface-assisted laser desorption ionization (SALDI)
• leaf
• agricultural chemicals

Plant leaves administered with systemic insecticides as agricultural chemicals were analyzed using imaging mass spectrometry (IMS). Matrix-assisted laser desorption/ionization (MALDI) is inadequate for the detection of insecticides on leaves because of the charge-up effect that occurs on the non-conductive surface of the leaves. In this study, surface assisted laser desorption/ionization with a sputter-deposited platinum film (Pt-SALDI) was used for direct analysis of chemicals in plant leaves. Sputter-deposited platinum (Pt) films were prepared on leaves administered with the insecticides. A sputter-deposited Pt film with porous structure was used as the matrix for Pt-SALDI. Acephate and acetamiprid contained in the insecticides on the leaves could be detected using Pt-SALDI-MS, but these chemical components could not be adequately detected using MALDI-MS because of the charge-up effect. Enhancement of ion yields for the insecticides was achieved using Pt-SALDI, accompanied by prevention of the charge-up effect by the conductive Pt film. The movement of systemic insecticides in plants could be observed clearly using Pt-SALDI-IMS. The distribution and movement of components of systemic insecticides on leaves could be analyzed directly using Pt-SALDI-IMS. Additionally, changes in the properties of the chemicals with time, as an indicator of the permeability of the insecticides, could be evaluated.

• 出版日期2016-5