High-Molecular Polyethyleneimine Coated Graphitized Carbon Black for Trace Determination of Strong Organic Bases

Abstract Tailing-free peaks even at the sub-nanogram level for amines have been obtained by using graphitized carbon black (GCB) as packing material modified with suitable amounts of KOH and a high molecular polyethyleneimine (PEI 40 M). This kind of column packing has been evaluated in terms of selectivity, retention time, efficiency and thermal stability. By the use of 1% PEI + 0.3% KOH modified GCB a clean chromatographic profile has been obtained for a C1 to C4 aliphatic amine water mixture, containing 1 ppm of each compound. Well-separated and well-defined peaks for a 0.5 ppm methylamine, dimethylamine, trimethylamine aqueous solution have been obtained within 1 min of elution time by decreasing the amount of PEI to 0.5%. Also, separations of ether solutions either of diamines or amphetamines have been exploited on a 1.5% PEI 40 M + 0.3% KOH + GCB column.