| Light scattering has been applied widely to macromolecule polymer sciences, colloid sciences, and life sciences research fields. Over ten years of development, resonance light scattering (RLS) has become a powerful and routine assay, which had often been eliminated in analysis as a kind of disturber. However, as the same as other spectral technique, it has been existed some disadvantage in aqueous solution, such as intricate interferences, poor reproducibility. To overcome these drawbacks, we develop light scattering/fluorescence ratiometry (LS/FL) to extend the application scope of RLS technique; it would undoubtedly enhance the performance of RLS technique in the aforementioned limitations. The mainly content of this contribution are as follows:1. RLS technique applied to the detection of tyrosine and the establishment of LS/FL:(1) Based on the selective reaction between tyrosine and silver nitrate, a new analysis method of tyrosine in clinic injection using silver nanoparticles (AgNPs) as RLS probe. The reaction mechanism and effect of condition on AgNPs are also considered.At the present of 2.0×10-3 mol/L sodium hydroxide, the phenolic hydroxide existed in tyrosine could deoxidize silver ion, and make it turn into AgNPs. All of these induce significantly enhanced RLS signals over the range of 320.0 nm - 500.0 nm with the maximum peak located at 382.0 nm. Linear relationships are achieved between the enhanced RLS intensity (ΔIRLS) at 382.0 nm and tyrosine concentration in the range of 0.8-12.0μmol/L when 2.0×10-4 mol/L of silver nitrate is employed. The 3σlimit of detection is 2.1×10-7 mol/L; the synthetic samples and commercial combination aminophenol injection is analyzed satisfactorily. (2) On account of the aggregation of organic dye EY and high sensitivity of RLS technique, we deal with the LS/FL analytical technique, based on the reaction between EY and HSA. The kinetic and thermodynamic constants are calculated token of chemical reaction, and then LS signal change influence of granule in aqueous solution on apparent LS intensity is discussed.pH 2.30, the emission intensities at 302.0 nm are enhanced gradually with the increase of human serum albumin (HSA), while the fluorescence intensity of EY at 544.0 nm is quenched, and the ratio of I302.0nm/F544.0nm is directly linear with the concentration of HSA over the range of 0.01-4.80 mg /L at room temperature, with a limit of determination (3σ) 0.50μg/L, when EY is fixed at 1.0×10-5mol/L. So we develop a ratiometry of protein based on both RLS and fluorescence signals using the interaction of EY with HSA as a model. The binding number (n) and binding constant (Kb) could be available with the values of 1.02 and 1.43×10-3 L/mol. The thermodynamic parameters, negative enthalpy (ΔH) and positive entropy (ΔS) values indicate that both electrostatic interactions and hydrophobic bond play a major role in the binding reaction. It has been revealed that, electrostatic effect quenched the fluorescence of EY, and aggregated between EY and HSA, leading to the formation of the stable complex EY-HSA and the enhanced LS signals, whereas the fluorescence intensity of EY was quenched. It has been found that this method takes on a distinguished sensitivity and more widely detected range for proteins content, for the ratio of RLS and fluorescence could eliminate a series of interferences, compared to routine RLS or fluorescence technique. The method was used to determine human serum samples and the results were coincident with the CBB G-250 method.2. We deal with the disperse character of carbon nanotubes (CNTs) in p-phenylenediamine (PPD), as well as the produce and grow up of silver nanoparticles upon the surface of CNTs, thus the spectrogram of compounds including RLS, absorption, and fluorescence could be obtained at the optimum conditions. We think that, it is acidity of solution not the CNTs number is tied in with the size and amount of compounds. It's indicated that CNTs has turned into a novel object to RLS technique, which has been kind of means in speck growth and aggregation investigation.(1) The interaction research between p-Phenylenediamine (PPD) and single-walled carbon nanotubes (SWCNTs) as well as multi-walled carbon nanotubes (MWCNTs) has been investigated. Having been tested by RLS, fluorescence, UV spectra, and granularity measurements, it could be found the strong interaction between MWCNTs and aryl-amine reagent; furthermore, the reaction mechanism has been brought forward.(2) The reaction of carboxylic MWCNTs and silver colloids obtained by the deoxidized silver ions are experimented, and also investigate the generation of Ag-MWCNTs nanoparticulates (AgMTNPs) using the modified MWCNTs as templates. When AgNPs have been adsorbed in the electronegative MWCNTs by static effect, the intensity signals of solution including fluorescence, absorption and RLS spectra are stronger visibly compared to those of AgNPs. It explains the appearance of metal nanoparticulates, and then reveals the investigative significance of metal-based complex nano-material and revise-quality matter.
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