Skip to Content
Merck

Electrochemical push-pull scanner with mass spectrometry detection.

Analytical chemistry (2012-07-14)
Dmitry Momotenko, Liang Qiao, Fernando Cortés-Salazar, Andreas Lesch, Gunther Wittstock, Hubert H Girault
ABSTRACT

This manuscript presents a push-pull electrochemical scanner able to image reactivity of initially dry surfaces by scanning electrochemical microscopy (SECM) and to probe molecules present or generated at the surface by mass spectrometry (MS). The proof-of-concept is demonstrated by coupling SECM with matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) for imaging latent human fingerprints, which had been in contact with picric acid used here as a model explosive. The push-pull electrochemical scanner has also been coupled with electrospray ionization mass spectrometry (ESI-MS) to assay the activity of surface spotted enzymes. These experimental studies are complemented by 3D finite element simulations solving Navier-Stokes and diffusion-convection differential equations to optimize the coupling between SECM imaging and mass spectrometry detection.

MATERIALS
Product Number
Brand
Product Description

Sigma-Aldrich
Picric acid, moistened with water, ≥98%
Sigma-Aldrich
Picric acid solution
Sigma-Aldrich
Picric acid solution, 1.3% in H2O (saturated)
Supelco
Picric acid solution, 100 μg/mL in acetonitrile, PESTANAL®, analytical standard