Porous silicon surfaces for metabonomics: Detection and identification of nucleotides without matrix interference

Abstract

AbstractIn present work, porous silicon surfaces (PSS) have been developed for time of flight mass spectrometric experiments (TOF‐MS) in the monitoring of nucleotides, commonly found as metabolites in the cell. The mass range of the studied molecules (∼ 400 amu) is common to several important messengers and other metabolites. Different porosified surfaces have been developed by means of electrochemical etching and different degree of porosity and pore size achieved as function of silicon dopant concentration, silicon resistivity, current density and the presence or absence of illumination along the process. As main conclusion, it can be said that an interesting commercial nucleotide (Cyclic adenosine monophosphate, c‐AMP) has been detected on low concentrations (∼hundreds of femtomols) for some of the fabricated porous surfaces. Taking into account that these concentrations are similar to the ones found in real samples, this result opens the possibility to the fabrication of DIOS (Desorption Ionization On Silicon) chips for the detection of nucleotides in biological fluids. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)