title: Small molecule analysis using laser desorption/ionization mass spectrometry on nano-coated silicon with self-assembled monolayers.
abstract: Matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) is an emerging technique for the determination of the molecular weight of biomolecules and their non-covalent complexes without fragmentation. One problem with this technique is the use of excess amounts of matrices, which may produce intense fragment ions and/or clusters at low mass ranges between 1 and 800 Da. These fragments lead to interference, especially concerning the signals of small target molecules. Here, a simple, reusable, and quite inexpensive approach was demonstrated to improve the effectiveness of laser desorption/ionization mass spectrometry (LDI-MS) analysis, especially for small molecules, without using matrix molecules. In this study, substrates with controllable morphologies and thicknesses were developed based on the self-assembly of silane molecules on silicon surfaces using N-(3-trimethoxysilylpropyl)diethylenetriamine (TPDA) and octadecyltrichlorosilane (OTS) molecules. Prepared substrates with nano-overlayers were successfully used in the analysis of different types of small target molecules, namely acrivastine, L-histidine, L-valine, L-phenylalanine, L-arginine, L-methionine and angiotensin I. Our substrates exhibited clear peaks almost without fragmentation for all target molecules, suggesting that these surfaces provide a number of important advantages for LDI-MS analysis, such as ease of preparation, costs, reusability, robustness, easy handling and preventing fragmentation.
authors.affiliation: The University of Akron, Department of Chemistry, Akron, OH 44325, USA.
authors.forename: Ömür
authors.initials: Ö
authors.lastname: Çelikbıçak
authors.forename: Gökhan
authors.initials: G
authors.lastname: Demirel
authors.forename: Erhan
authors.initials: E
authors.lastname: Pişkin
authors.forename: Bekir
authors.initials: B
authors.lastname: Salih
mesh_terms: D000803:Angiotensin I / Q000032:analysis; D001120:Arginine / Q000032:analysis; D006639:Histidine / Q000032:analysis; D008715:Methionine / Q000032:analysis; D049329:Nanostructures / Q000737:chemistry*; D017646:Organosilicon Compounds / Q000737:chemistry*; D010649:Phenylalanine / Q000032:analysis; D011073:Polyamines / Q000737:chemistry*; D012821:Silanes / Q000737:chemistry*; D012825:Silicon / Q000737:chemistry*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*; D014633:Valine / Q000032:analysis
chemical_list: C575344:N-(3-trimethoxysilylpropyl)diethylenetriamine; D017646:Organosilicon Compounds; D011073:Polyamines; D012821:Silanes; C061189:octadecyltrichlorosilane; D010649:Phenylalanine; D006639:Histidine; D000803:Angiotensin I; D001120:Arginine; D008715:Methionine; D014633:Valine; D012825:Silicon