“Touch&Play” Wood Typification by the MasSpec Pen

Abstract

We have investigated the ability of a MasSpec Pen (MSPen) “three-in-one” (extraction, transfer, and ionization) device coupled to a mass spectrometer to provide instantaneous chemical profiles that could promptly characterize wood samples from the mahogany (Meliaceae) family. For that, we selected a set of five representative wood species, that is, Brazilian mahogany (Swietenia macrophylla, also known as Honduran mahogany), two African mahoganies (Khaya ivorensis and Khaya senegalensis), and two “nongenuine” (“fake”) mahogany woods: cedar (Cedrela odorata) and andiroba (Carapa guianensis). By simply touching the superficially polished wood surface and after 3 s of automatic extraction, profiles of highly characteristic markers that effectively discriminated all five mahoganies were detected. The superficial surface of a wood Brazilian mahogany sample as compared with internal wood accessed via deep sanding showed minor profile changes mainly by shifts in the relative abundances of the wood markers, indicating that aging only marginally changes MSPen wood signatures. The direct “touch&play” analysis offered by MSPen was therefore found to provide nondestructive, fast, sample-preparation-free, and reliable typification of woods. This “spatially free” device also allows broad screening because multiple points on the whole surface of any small or large-size intricate wood sample can be rapidly analyzed, demonstrating its high potential for forensic investigations, particularly for endangered species such as the Brazilian mahogany.