| Resonance light scattering technique is a newely established technique for characterizing supramolecular assemblies and their analytical applications developed by a common spectrofluorometer. With this technique, we have proposed highly sensitive analytical methods of DNA, proteins, trace amount metallic ions and surfactants, characterized the characteristic spectrum of molecular aggregation, and the structure of the supramolecular double-stranded DNA. By examining RLS spectral features of four systems including Al3+-DNA, azoviolet-cationic surfactants, fast red VR-proteins, ponceau G-proteins in this thesis, and proved that the instrumental conditions of spectrofluorometer have strong effect on the shape of resonance light scattering (RLS) spectra. Molecular absorption of sample will lower the detection sensitivity of RLS method. Thus a correction theory was established by introducing a correction factor, which measured molecular absorption directly on a common spectrofluorometer by using an absorption cell holder. According to data that measured on the same instrument, the corrections of resonance light scattering spectra of the three systems including fast red VR-proteins, ponceau G-proteins and α,β,γ, δ-tetrakis[4-(trimethylammoniumyl)pheny]porphine(TAPP)-DNA have been discussed.In acidic medium of pH 2.21, the interaction of Al3+ with deoxyribonucleic acid (DNA) results in enhanced resonance light scattering spectra, characterized by the peak at 291nm. Al3+has no chromothore, and its light absorption has little effect on the RLS spectra of the interaction between Al3+ and DNA. So the sensitivity of determination of DNA with Al3+ is very high, and the linear range is wide. A simple assay of cationic surfactants in water samples was developed based on the measurements of enhanced resonance light scattering. On the conditions of pH 6.09 and ionic strength 0.03 mol/L, the interactions of azoviolet (AV) with cationic surfactants, including zephiramine (Zeph), and cetyl trimethyl ammonium bromide (CTMAB), result in enhanced RLS signals characterized by the peaks of 470.0 nm,485.0 nm and 495.0 nm. Determinations of cationic surfactants in synthetic and tap water samples were successfully made with the recovery of 90.5-108.2%.The experiments stated above have showed that RLS spectra vary with the molecular absorption of systems and the instrumental conditions. Just like the correction of fluorescence spectra, we have corrected the instrumental factors and the inner fittering of the molecular absorption in the systems by introduing a correction factor.In an acidic medium, the interaction of fast red VR (FRV) and Ponceau G (PG) with proteins including bovine serum albumin (BSA), human serum albumin (HSA), pepsin (Pep) a-chymotrypsin (Chy), and lysozyme (Lys) was characterized by measuring enhanced resonance light scattering signals. The maximum RLS peaks were 287.0 nm and 288.0 nm, respectively. The limits of determination for BSA, HSA, Lys, y-IgG were below 25.0 ng/ml. The present method is successfully applied to determine proteins in synthetic samples, and the total content of proteins in human blood plasma samples, respectively. The results for determination human blood serum by this method are consistent with those obtained by the Coomassie brilliant blue G-250 assay. By using an absorption cell holder to change the propagation direction of the incident light beam of a common spectrofluorometer, the molecular absorptions of FRV-porteins and PG-porteins systems were directly measured through a spectrofluorometer, and corrected the RLS intensities of FRV-porteins and PG-porteins with a correction factor. With measurements of the corrected resonance light scattering (CRLS) signals of the interaction of fast red VR (FRV) with proteins and PG with proteins, respectively, we have proved that the present correction for the RLS spectra in terms of the molecular absorption of excitation and scattering radiation could improve the detection sensitivity by about two fold.We corrected the RL...
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