Surfactant And The Interaction Between The Neutral Red, Procaine Hydrochloride And Human Serum Albumin

1. The electrochemical properties of PCN on the surface of the platinum electrode were studied by the cyclic voltammetry, and the effect of anionic surfactant SDS on the electrochemical reducing potential was researched. The fluorescence self-quench of PCN was studied with increase of concentrations of inorganic salts. Both intensities of the characteristic peaks of UV-absorption spectrum and the fluorescence emission spectrum of PCN increased with the increase of SDS concentration.2. The effect of cationic surfactant CTAB and procaine hydrochloride on the transformation of two structure of neutral red was investigated by methods of UV-Vis, fluorescence spectra, surface tension and conductivity. The results show that with increasing CTAB concentration, the content of neutral form of neutral red increased and the content of acidic form decreased. The Gibbs free energy of the transformation reaction decreased with the addition of CTAB, the transformation reaction became easier. The critical micelle concentration of CTAB was not changed. When procaine hydrochloride was added to the micelle or CTAB/C5H11OH/H2O O/W microemulsion system, the content of acidic form increased and the content of neutral form decreased. NR was located in the railings of the CTAB micelles. It was much nearer to the core in rod-like micelle than in spherical micelle.3. The interactions of anionic surfactant SDS and procaine hydrochloride with the acidic form of neutral red (NRa) are studied by the methods of UV-Vis, fluorescence spectra, surface tension and conductivity. Neutral red accelerates the formation of the SDS micelle. In dilution solution, the intensities of UV-Vis absorbance and fluorescence emission spectra of NRa decrease when NRa interacts with SDS molecule. The spectra intensities of NRa increase with the increase of SDS concentration. NRa is absorbed on the surface of SDS micelle, and may be located in the deep layer of the palisade layer of SDS rod-like micelle. In SDS micelle or SDS/C5H11OH/H2O O/W microemulsion system, with the addition of PCN, the spectra intensities of NRa decrease.