The binding characteristics of the interaction between 3-(2-cyanoethyl) cytosine and human serum albumin.

The binding characteristics of the interaction between 3-(2-cyanoethyl) cytosine (CECT) and human serum albumin (HSA) were investigated using fluorescence, UV absorption spectroscopic and molecular modeling techniques under simulative physiological conditions. The intrinsic fluorescence intensity of HSA was decreased with the addition of CECT. The fluorescence data handled by Stern-Volmer equation proved that the quenching mechanism of the interaction between CECT and HSA was a static quenching procedure.

[Determination of protein in biological samples by synchronous fluorescence].

The authors studied the characterization of synchronous fluorescence spectra of 5-methyluridine-protein system; the spectral characterization and intensity of synchronous fluorescence were related to the value of deltalamda, reaction medium, reagent concentration, ionic strength, addition sequence, reaction time, reaction temperature, and so on. On basis of the experimental results, the new method for the determination of the proteins was developed with 5-methyluridine as a molecular probe. Under the optimum experimental conditions, the synchronous fluorescence intensities of 5-methyluridine-HSA systems were in good proportion to the HSA concentration of the system in the range of 1.

A study on the interaction between 5-Methyluridine and human serum albumin using fluorescence quenching method and molecular modeling.

This work was designed to study the interaction between 5-Methyluridine and human serum albumin (HSA) under simulative physiological conditions using fluorescence spectroscopy in combination with molecular modeling technique for the first time. Static quenching was suggested by the fluorescence measurement. The binding constants (K) were calculated according to the relevant fluorescence data at different conditions including temperature.

[Studied on the determination of protein by probe of zinc 5-aminosalicylate].

Zinc 5- aminosalylicylate (5-ASZ), a new creative medicine, can react with serum albumin to form a complex. Based on this, a new method for the determination of proteins by synchronous fluorescence spectra under simulated physiological conditions was established using 5 - ASZ as a fluorescence probe. The spectral characterization and intensity of synchronous fluorescence were related to the value of deltalambda, reaction medium and reaction temperature, and so on.

Synchronous fluorescence determination and molecular modeling of 5-Aminosalicylic acid (5-ASA) interacted with human serum albumin.

In this paper, we proposed a new method for the determination of either human serum albumin (HSA) or 5-Aminosalicylic acid (5-ASA) by synchronous fluorescence spectra and examined the interaction between them using the molecular modeling method under simulative physiological conditions. The optimum conditions of synchronous fluorometric determination of HSA were investigated and the method was successfully applied to the determination of 5-ASA added to serum, urine, and saliva samples. The linear range of the determination of HSA and 5-ASA were 1.

Binding of daunorubicin to human serum albumin using molecular modeling and its analytical application.

This study was designed to examine the interaction of daunorubicin with human serum albumin (HSA) for the first time by fluorescence spectroscopy in combination with UV absorption and molecular modeling under simulative physiological conditions. The quenching mechanism was suggested to be static quenching according to the fluorescence measurement and the linearity of Scatchard plot indicated that daunorubicin bound to a single class of binding sites on HSA. The thermodynamic parameters, enthalpy change (DeltaH) and entropy change (DeltaS) were calculated to be -16.

Fluorescent investigation of the interactions between N-(p-chlorophenyl)-N'-(1-naphthyl) thiourea and serum albumin: synchronous fluorescence determination of serum albumin.

The interactions between N-(p-chlorophenyl)-N'-(1-naphthyl) thiourea and serum albumin were investigated by fluorescence spectroscopy and UV absorption spectrum under physiological conditions. The results of spectroscopic measurements suggested that N-(p-chlorophenyl)-N'-(1-naphthyl) thiourea should have a strong ability to quench the intrinsic fluorescence of both bovine serum albumin and human serum albumin through static quenching procedure, and the hydrophobic interaction was the predominant intermolecular force stabilizing the complex. Thermodynamic parameter enthalpy changes (DeltaH) and entropy changes (DeltaS) were calculated according to the Vant'Hoff equation.

[Spectral study and determination of metoclopramide and procaine hydrochloride by sequential injection analysis].

A sequential injection spectrophotometric method is proposed for the determination of metoclopramide or procaine hydrochloride, based on the reactions of metoclopramide and procaine hydrochloride with cerium(IV) in sulfuric acid medium. Red intermediate products were observed and were found unstable so that their analytical use is only possible by sequential injection technology. For metoclopramide, the detection limit is 6.

[Speciation analysis of selenium by flow-injection catalytic spectrophotometry].

A new flow-injection catalytic spectrophotometric method was proposed for the determination of Se(IV) based on its catalytic effect on the reduction reaction of azure I by Na2S in pH 7.0 citric-acid sodium-hydrogen-phosphate buffer solution. Some different schematic diagrams of FIA were compared.

[Inhibitory kinetic fluorimetric determination of trace aniline].

An inhibitory kinetic fluorimetric method is reported for the determination of trace aniline. The proposed method is based on the inhibitory effect of aniline on the reaction of potassium periodate oxidation of rhodamine 6G in phosphoric acid medium. The detection limit is 7.

Micellar electrokinetic chromatography with laser-induced fluorescence detection for rapid and sensitive analysis of two new bioactive reagents using dynamic covalent coating.

A simple, rapid, selective, and sensitive micellar electrokinetic chromatography (MEKC) with laser-induced fluorescence detection (LIF) method was developed, using hexamethyldisilazane (HMDS) as dynamic covalent coating (DCC), for the analysis of two new bioactive agents N-n-hexyl-N'-(sodium p-aminobenzenesulfonate) thiourea (HXPT) and N-n-undecyl-N'-(sodium p-aminobenzenesulfonate) thiourea (UPT) derivatized with 4-chloro-7-nitrobenzo-2-oxa-1,3-diazole. MEKC methods both not using DCC and using DCC were investigated. In a series of optimization steps, DCC and a running buffer of 20 mM Na2B4O7 + 16 mM SDS + 8% acetonitrile were applied for determination of the derivatives.

Fluorescence spectroscopy studies on 5-aminosalicylic acid and zinc 5-aminosalylicylate interaction with human serum albumin.

The interaction between 5-aminosalicylic acid (5-ASA) or zinc 5-aminosalylicylate (5-ASZ) and human serum albumin (HSA) was studied by fluorescence spectroscopic technique. The binding constants of 5-ASA or 5-ASZ with HSA were determined at different temperatures under the optimum conditions. The binding sites were obtained and the acting force were suggested to be mainly hydrophobic.

Interactions between 1-benzoyl-4-p-chlorophenyl thiosemicarbazide and serum albumin: investigation by fluorescence spectroscopy.

The interactions between 1-benzoyl-4-p-chlorphenyl thiosemicarbazide (BCPT) and bovine serum albumin (BSA) or human serum albumin (HSA) have been studied by fluorescence spectroscopy. By the analysis of fluorescence spectrum and fluorescence intensity, it was showed that BCPT has a strong ability to quench the intrinsic fluorescence of both bovine serum albumin and human serum albumin through a static quenching procedure. The binding constants of BCPT with BSA or HSA were determined at different temperatures based on the fluorescence quenching results.