Electrospray Ionization Mass Spectrometric Behavior of Ethoxylates Surfactant

Etyoxylates are an important group of nonionic surfactants.A method of direct infusion analysis by electrospray ionization(ESI) time-of-flight(TOF) mass spectrometry(MS) has been used to determine nonylphenol ethoxylates(NPEO) adducts. Common sodium and potassium adducts~+,~+ were observed in spectrum.With the addition of MgCl_2,NPEO form the adduct of M+MgCl~+.Through comparison of spectra,addtion of various amount of K~+ into NPEO samples could display the change of peak intensity between ~+ and ~+.ESI/MS high-resolution spectrum was used to confirm corresponding to M+NH_4~+.