Can voltammetry distinguish glycan isomers?
The analysis of glycan isomers is an important task in glycomics. This study reveals for the first time that two oligosaccharide pentamers can be distinguished electrochemically. 3 alpha,6 alpha-mannopentaose (MPO) and verbascose (VBS) were modified using Os(VI)-temed and the carbohydrate adducts measured directly in the reaction mixture using cyclic voltammetric (CV) and square wave voltammetric (SWV) stripping at the hanging mercury drop electrode. Some CV and SWV responses of MPO were found to differ from those of VBS at full electrode coverage, requiring mu M concentrations at short accumulation time-intervals. Similar results were obtained at partial electrode coverage at nM concentrations. These results afford an opportunity for the development of a new simple and inexpensive glycan analysis. (C) 2014 Institute of Chemistry, Slovak Academy of Sciences