• Home
  • Search Results
  • In situ analysis of agrochemical residues on fruit using ambient ionization on a handheld mass spectrometer.

In situ analysis of agrochemical residues on fruit using ambient ionization on a handheld mass spectrometer.

The Analyst (2011-09-06)
Santosh Soparawalla, Fatkhulla K Tadjimukhamedov, Joshua S Wiley, Zheng Ouyang, R Graham Cooks
ABSTRACT

We describe a rapid in situ method for detecting agrochemicals on the surface or in the tissue of fruit using a portable mass spectrometer equipped with an ambient ionization source. Two such ionization methods, low temperature plasma (LTP) and paper spray (PS), were employed in experiments performed at a local grocery store. LTP was used to detect diphenylamine (DPA) directly from the skin of apples in the store and those treated after harvest with DPA were recognized by MS and MS/MS. These data therefore allowed ready distinction between organic and non-organic apples. DPA was also found within the internal tissue of purchased apples and its distribution was mapped using LTP. Similarly, thiabendazole residues were detected on the skin of treated oranges in a grocery store experiment in which paper spray was performed by wiping the orange surface with a moist commercial lens wipe and then applying a high voltage to ionize the chemicals directly from the wipe. The handheld mass spectrometer used in these measurements is capable of performing several stages of tandem mass spectrometry (up to MS(5)); the compounds on the fruit were identified by their MS/MS fragmentation patterns. Protonated DPA (m/z 170) produced a characteristic MS(2) fragment ion at m/z 92, while thiabendazole was identified by MS(3) using precursor to fragment ion transitions m/z 202 →m/z 175 →m/z 131. These particular examples exemplify the power of in situ analysis of complex samples using ambient ionization and handheld mass spectrometers.

MATERIALS
Product Number
Brand
Product Description

Sigma-Aldrich
Thiabendazole, ≥99%, powder
Supelco
Thiabendazole, PESTANAL®, analytical standard
Sigma-Aldrich
Thiabendazole, BioReagent, suitable for plant cell culture, powder
Supelco
Thiabendazole, Pharmaceutical Secondary Standard; Certified Reference Material
Tiabendazole, European Pharmacopoeia (EP) Reference Standard

Social Media

LinkedIn icon
Twitter icon
Facebook Icon
Instagram Icon

Merck

Research. Development. Production.

We are a leading supplier to the global Life Science industry with solutions and services for research, biotechnology development and production, and pharmaceutical drug therapy development and production.

© 2021 Merck KGaA, Darmstadt, Germany and/or its affiliates. All Rights Reserved.

Reproduction of any materials from the site is strictly forbidden without permission.