Application Research Of Spectral Analysis Of Proteins

The linear sweep oscillopolarography is simple, quick and high veraciousness analytical means. In recent years, the oscillopolarography has been widely used in many aspects. In this thesis, three new methods have been investigated for determination of gallium, cholesterin and nicotine respectively by oscillopolarography.1. A new method for direct determination of trace gallium by oscillopolarography is investigated. In 0.1mol/L acetate buffer solution (pHS.O), the gallium and bromopyrogallol red form a red complex, which give a sensitive reduction peak at mercury electrode with peak potential of-1.15V. The peak currents are linear relationship with gallium concentrations in the range of 2.0 X 10"7mol/L -1.0 X 10'5mol/L with detected limit of 1.0 X 10"7mol/L. This method was used to detect trace gallium in pure aluminum samples with satisfactory results. Moreover, the kinetics parameters of electrode reaction were investigated by multi-electrochemical techniques.2. Cholesterin is adsorption on the mercury electrode surface and then be reduced at potential of-1.07V. By this character, a sensitive method for direct determination of cholesterin is established by oscillopolarography. In 0.2mol/L Na2HPO,t-KIl2PO4 buffer solution, the peak currents are linear relationship with cholesterin concentrations in the range of 1.995 X 10'6mol/L-7.09X 10'4mol/L with detection limit of 1.8 X 10"6mol/L (single / noise = 1). This method has been used for detecting cholesterin in serum with satisfactory results.3. A new method for directing nicotine in cigarettes is investigated by oscillopolarography. In 0.2mol/L oxalic acid, a sensitive reduced peak is obtained at -1.22V. The peak currents are linear relationship with nicotine concentrations in the range of 1.5|ig/mL~31.5u,g/mL with the detection limit of 0.37fag/mL. This method has been used for direct determination of trace nicotine in cigarette with good results.