Study On HPLC Stationary Phase Of PAH/Derivatives Of PEMA Multilayers

A phenylethylamine derivative (PEMAPEA) and a phenylalanine derivative (PEMAPHE)of poly (ethylene-alt-maleic acid) were synthesized from poly (ethylene-alt-maleic anhydride)and were characterized with FT-IR,1H NMR. The poly(allylamine hydrochloride)(PAH)/PEMAPEA multilayer was fabricated on the quartz slide by using the layer-by-layertechinque and the growth of the multilayer was monitored with a UV-Vis spectrophotometry.Influences of the concentration of polyelectrolytes and the concentration of NaCl added in thepolyelectrolyte solutions were studied. The results show the absorbance of thePAH/PEMAPEA multilayer increasing regularly with the number of the bilayers. At low(<0.4mmol·L-1) or high (4.0>mmol·L-1) polyelectrolyte concentration the films grow slowlyand linearly with the number of deposition cycles. When the polyelectrolyte concentration isin the range of0.4to4.0mmol·L-1, the multilayers grow rapidly and linearly after the initialnonlinear deposition stages. The growth rate of the multilayers increase with theconcentration of NaCl added in PAH solution. But the deposition amounts of the films hardlyvary as the NaCl concentration added in PEMAPEA solution increasing when the NaCladded in the PAHsolution is constant. These indicate the addition of NaCl in polymer solutionchanges only the deposition of PAH on the surface of PAH/PEMAPEA multilayer film.The PAH/PEMAPEA multilayer film was fabricated on the surface of porous sphericalsilica gel by using the layer-by-layer technique to build high performance liquidchromatography stationary phase. Infrared spectroscopy and Elemental analyses resultsconfirmed the existence of the organic polymer on the silica gel surface. Under reversedphase conditions, the chromatographic performance and retention mechanism of thePAH/PEMAPEA multilayer film stationary phase were evaluated by using different soluteincluding aromatic compounds, carbamate pesticides, organophosphorus pesticides andorganochlorine pesticide. When the alkyl chain of alkylbenzene was longer or the number ofpolycyclic aromatic hydrocarbons’aromatic ring increased, the analyte retention values wereincreased on multilayer film stationary phase, in addition, when the polarity of mobile phaseincreased, the capacity factor of analyte increased, which showed that hydrophobic and π-π interactions were existing between the PAH/PEMAPEA multilayer film stationary phase andanalytes.The PAH/PEMAPHE multilayer film stationary phase was fabricated on the surface ofporous spherical silica gel by using the layer-by-layer technique. Under reversed phaseconditions, the chromatographic performance and retention mechanism of the stationaryphase were evaluated by using different analysisc including aromatic compounds, anilines,organophosphorus pesticides, carbamate pesticides, and benzene drugs, and the resultindicated that there were hydrophobic and π-π interaction between the PAH/PEMAPHEmultilayer film stationary phase and analysis including, which was similar to thePAH/PEMAPEA multilayer film stationary phase.