Study On The Interaction Of Some Pharmaceuticals With Biological Acromolecule And Dyes By Molecular Spectrometry And Their Analytical Applications

When the material molecule receives the light (electromagnetic wave), the absorption, reflection or transmission and emission, scattering will take place. The molecule spectrum is obtained from dividing these light phenomena, it includes abundant information such as the composition, structure, physical and chemical characteristics, reaction mechanism and so on. Molecular Spectrometry is the analytical method of measuring and characterizing, molecule spectral analysis is commonly used analysis technology of the qualitative and quantitative analysis, it is the important experimental method of determining and indentifing molecular structure, it is the development foundation of chemical reaction theory and experimental verification. According to difference ranges of absorbing the electromagnetic wave, it can be divided into ultraviolet-visible spectrum, the near-infrared spectrum and infrared spectrum etc; according to the difference electromagnetic wave emission method, it can be divided into the molecular fluorescence, the phosphorescence and the scattering spectrum and so on. This article studies on the interaction of some pharmaceuticals with biological macromolecule and dyes by Molecular Spectrometry and their analytical applications: 1. Fluorescence Quenching of Bovine Serum Albumin by Natamycin, The binding site number n and the binding constant K_A , corresponding thermodynamic parametersΔG,ΔH andΔS at different temperatures were calculated; 2. The interaction of chondroitin sulfate with bovine serum albumin, we studied the RRS and SOS spectra characheristics of the system; 3. Study on the interaction of Chlorphenamine with erythrosine and its analytical applications; 4. Study on the interaction of Sibutramine with halofluorescein and their analytical applications; 5. Study on the spectra characheristics of ternary ion-association complexes of Doxorubicin-Me(II)-Erythrosine system and thair analytical applications.1 Natamycin - bovine serum albumin systemThe interaction of natamycin and bovine serum albumin (BSA) was studied with fluorescence spectroscopy and synchronous fluorescence. The binding distance(r=1.08 nm) and transfer eficiency (E=22.99%) between natamycin and BSA were obtained according to the theory of F(o|¨)rster non-radiation energy transfer. Furthermore, the effect of natamycin on the conformation of BSA was also analyzed using synchronous fluorescence spectrometry. Finally, the thermodynamic data show that the interaction forces of BSA with natamycin is the hydrogen bond and van der waals interaction. In addition, in neutral medium, natamycin could bind with BSA to form complexes, which would result in the quenching of the intrinsic fluorescence (λ_ex/λ_em=285 nm/347 nm) of the BSA. The quenching intensity (ΔF) was directly proportional to the concentration of the natamycin. Therefore, a new analytical method was established to determine trace ntamycin in yoghurt products.2 Chondroitin sulfate- bovine serum albumin systemIn pH 3.5 B-R buffer solution, BSA with positive charge and chondroitin sulfate (CS) with negative charge formed self-assembled polymer via electrostatic interaction in aqueous solution. We studied the resonance rayleigh scattering (RRS) and second-order scattering (SOS) spectra of CS-BSA system, RRS and SOS spectra were found by synchronous scanningΔλ=0 and scanning the fluorescence spectrum mode, respectively; we researched the RRS and SOS spectra characheristics of CS-BSA and BSA-CS system, it is found that RRS intensity can be enhanced after the interaction of CS and BSA, and there was a linear relationship between the RRS intensity and CS or BSA concentration. So a new method for the sensitive and rapid determination of CS and BSA can be developed. In addition, the RRS enhanced mechanism has been discussed.3 Chlorphenamine maleate - erythrosine system3.1 Fading spectrophotometric determination of chlorphenamine maleate with erythrosineIn weak acidic medium, Chlorphenamine Maleat (CPM) react with halogenated fluoresce dyes such as erythrosine (ET) and eosinY (EY) to form the ion-association complex through electrostatic and hydrophobic interaction, the color of solutions changes obviously, erythrosine system has a remarkable color fading reaction and the fading wavelengths is 525 nm, the concentration of CPM obeys Beer's law in the range of 0.1-4.0μg·mL^-1, the molar absorptivity (ε) is 3.5×10⁴ L·mol^-1·cm^-1. The method is sensitive, simple and rapid, it has been applied to the determination of CPM in tablets and urine with satisfactory results.3.2 The fluorescence quenching and resonance Rayleigh scattering enhancement of ET-CPM system and its analytical applicationIn pH 4.4 BR buffer medium, erythrosine (ET) and Chlorphenamine Maleate (CPM) could form ion-association complex, which leads to the quenching of fluorescence and synchronized fluorescence, and the significant enhancement of resonance Rayleigh scattering (RRS) of erythrosine. The fluorescence and RRS intensities have linear relationship with the CPM concentration in the range of 0.24-8.0μg·mL^-1, and 0.08-3.6μg·mL^-1, respectively. The method could be applied to the determination of CPM in urine samples with satisfactory results. The mechanisms of the RRS enhancement and fluorescence quenching were discussed as well.4 Sibutramine - halofluorescein systems4.1 Study on determination of sibutramine by fluorescence quenching and fading spectrophotometryIn weak acid buffer solutions, 3 halofluorescein dyes, such as, ethyl eosin (EE), erythrosine(ET) and phloxine(PX), can react with Sibutramine(SH) to form ion-association complexes, which not only results in the quenching of fluorcence, but also results in the great decrease of absorbance. In this work, the spectral characteristics of fluorcence and absorption spectra, the optimum conditions of the reaction were investigated. A new method for the determination of Sibutramine by using halofluorescein as a probe has been developed. ET-SH system has the highest sensitivity for the fading reaction. There is a linear relationship between the absorption intensities and SH concentration in the range of 0.1-4.0μg·mL^-1, The detection limit for SH is 0.06μg·mL^-1; PX-SH system has the highest sensitivity for the fluorcence quenching reaction, the linear range is 0.2-4.6μg·mL^-1(λ_ex/λ_em=540 nm/560 nm). The detection limit for SH is 0.09μg·mL^-1. In addition, the reasons for the the quenching of fluorcence and the fading of absorption spectra were discussed.4.2 Studies on the interaction of Sibutramine with halofluorescein and their analytical application by resonance Rayleigh scattering spectraThe interaction of halofluorescein, such as, ethyl eosin (EE), erythrosine (ET) and phloxine(PX) with Sibutramine(SH) have been investigated by resonance rayleigh scattering spectra(RRS). SH can react with halofluorescein to form ion-association complexes, which can result in the significant enhancement of RRS intensity. The maximum scattering peaks esist at nm for EE-SH, nm for ET-SH and nm for PX-SH. The RRS spectral characteristics, the the optimum conditions and influencing factors have been studied for EE-SH, ET-SH and PX-SH reaction systems. The intensity of RRS is directly proportional to the concentration of SH in a certain concentration range, the detection limit for SH was 32 ng·mL^-1 (EE-SH system), 28 ng·mL^-1(ET-SH system) and 21 ng·mL^-1(PX-SH system), respectively. The polarization of light was measured, the polarization value P of the RRS at 573 nm is measured to be 0.95, the experimental facts revealed that the scattering peak of ET-halofluorescein mainly consists of resonance scattering and few resonance fluorescence. In addition, the reasons for intensity enhancement of RRS have been discussed. 5 Doxorubicin-Me (II)-erythrosine systemsIn NaAc-HAc buffer solution, the Doxorubicin reacted with Cu(II) and Pd(II) ion to form cation chelates which further reacted with anion halofluorescein dyes, such as ethyl eosin(EE), erythrosine(ET) and phloxine(PX) to form ternary association-complexes. As a result, the significant enhancements of RRS intensities were observed. Their spectral characteristics of RRS were similar, and the maximum RRS wavelengths were at 570 nm. The increments of RRS intensity were different in the series of Pd (II)>Cu (II). The enhanced RRS intensities were proportional to the concentration of DOX, the detection limit for DOX is 8.2 ng·mL^-1; a kind of new experimental method of measuring DOX was provided...