Direct Analyte-Probed Nanoextraction (DAPNe) Coupled to Matrix-Assisted Laser Desorption Ionization (MALDI) for Examination of the Ink Chemistry on Documents

• NCJ Number: 255252
• Journal: Forensic Chemistry Volume: 2 Dated: November 2016 Pages: 86-92
• Date Published: November 2016
• Author(s): Vivian Huynh; Mandy S. Phelps; Teresa D Golden; Guido F Verbeck
• Length: 7 pages
• Grant Number(s): 2013-R2-CX-K007
• Agencies: NIJ-Sponsored
• Publication Type: Research (Applied/Empirical)

Annotation

This article reports on the coupling of matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) to direct analyte-probed nanoextraction (DAPNe) through the use of nanomanipulation for the analysis of ink chemistry on documents.

Abstract

DAPNe was first used to extract ink from the document and then deposit the sample on the MALDI plate. Through this method, cutting the document for MALDI-MS analysis was avoided. DAPNe extracted ink from documents with minimal to no visible destruction. Specific dyes and binding agents in the extracted ink were monitored with mass spectrometry. Different matrices, 1, 5-diaminonapthalene (DAN), 2, 5-dihydroxybenzoic acid (DHB), and silver nanoparticles, were tested to compare intensity enhancement of the mass spectra signals. The advantages of using MALDI-MS coupled to DAPNe were shown by characterizing Crystal Violet, Basic Yellow 2, Rhodamine B, and polyethylene glycol from red and blue pens, black pen, and a black inkjet printer cartridge. (publisher abstract modified)