Yali Han

Rapid and sensitive determination of proteins by enhanced resonance light scattering spectroscopy of sodium lauroyl glutamate.

A rapid and sensitive method for the determination of proteins is proposed based on the measurements of the enhanced resonance light scattering (RLS) spectroscopy of sodium lauroyl glutamate (SLG). Under the optimum conditions, the interaction between SLG and proteins occurred rapidly, resulting in greatly enhanced RLS intensity with the maximum peak located at 394nm. It was found that the enhanced RLS intensities were in proportion to the concentrations of proteins in the range of 0.01-3.1mugml(-1) depending on the kind of proteins. The detection limits were below 6ngml(-1). Compared with some other methods for the determination of proteins, this method shows high sensitivity, low detection limit and simplicity. This is an inexpensive, simple and fast one-step procedure which requires only measuring the RLS intensities. Human serum samples were determined with satisfactory results.

Determination of dextrin based on its self-aggregation by resonance light scattering technique

A novel free-probe assay of dextrin was established based on the resonance light scattering (RLS) enhancement in aqueous solution due to the self-aggregation of dextrin. The RLS intensity was well proportional to the concentration of dextrin over the wide range 0.2-14microg mL(-1) and a detection limit 0.02microg mL(-1) was obtained in the optimum conditions. The effect factors such as pH, buffer medium, holding time, ionic strength and temperature were studied in detail. Little or no interference was presented in the detection when adding coexisting substances including various metal ions and some saccharine in the solution. The assay proposed owns the advantages of easy operation, rapidity, sensitivity and practicability. Three synthetic samples and three kinds of medicine samples were analyzed with satisfactory results.

A High-Sensitivity Assay of Nucleic Acids with Tetraphenyl Porphyrin Cobalt Chlorine by Resonance Light Scattering Technique

Abstract A novel probe, tetraphenyl porphyrin cobalt chlorine (CoTPPCl), is first applied to determine nucleic acids at the nanogram level based on the measurement of resonance light scattering (RLS) signals, which result from the interaction of CoTPPCl with nucleic acids. Under pH 6.37 conditions, the reaction between CoTPPCl and nucleic acid enhances the weak resonance light scattering (RLS) signal of CoTPPCl, and the enhanced light scattering intensity is proportional to the concentration of nucleic acid. The method is sensitive (3.45 ng/mL for ctDNA), simple (one step and a common fluorimeter), and tolerant of the metal ions and other coexistent substances. The mode of the combination between CoTPPCl and nucleic acids and the reasons for RLS enhancement are clearly clarified. Synthetic samples were determined with satisfactory results.

A sensitive rutin assay using a simple probe manganese sulfate based on its novel resonance light scattering decrease phenomenon.

A novel resonance light scattering (RLS) decrease method was developed to determine rutin with a simple probe manganese sulfate. At pH 7.5, the strong RLS intensity of manganese sulfate was remarkably decreased by the addition of rutin with the maximum peak located at 389.0 nm. Under the optimum conditions, a good linear relationship between the changes of RLS intensities of manganese sulfate with and without rutin and the concentrations of rutin was obtained over the range of 0.49-24.4 microg ml(-1) and a low detection limit (3sigma) 0.42 microg ml(-1) was achieved in the mean time. Based on this approach, a novel method for quantitative analysis of rutin is proposed in this paper. The method proposed was also applied successfully to the determination of rutin in commercial pharmaceutical preparations of compound rutin tablets and human urine samples. The assay is sensitive, rapid, inexpensive, practical and relatively free from interference generated by coexisting substances.