Resonance Rayleigh scattering study of the interaction of bleomycinA_5 with nucleic acids and its analytical application

The interaction of bleomycinA5 with nucleic acids has been investigated by using resonance Rayleigh scattering (RRS), molecular absorption and fluorescence spectra. The result shows that in near pH 2.2 buffer medium and absence of any metal ions, nucleic acids are capable of binding with bleomycinA5 (BLMA5) to form complexes which can remarkably enhance the RRS intensity and result in batho- chromic and hyperchromic molecular absorption of nucleic acids and fluorescence quenching of bleomycinA5. The RRS spectral characteristics for the binding products of bleomycinA5 with various DNA and RNA are similar, and the maximum RRS peaks are at 301 nm for ctDNA and sDNA, 370 nm for hsDNA, 310 nm for RNAtypeVI and RNAtypeIII, respectively. The increments of RRS intensity are greatly different in which DNA enhances greatly and RNA enhances lightly. In this work, the optimum condi- tions of the interaction and some influencing factors have been investigated. The reaction mechanism and a binding model for the interaction of BLMA5 with the nucleic acids are discussed. In addition, a highly sensitive, simple and rapid new method for the determination of DNA has been developed. The detection limits (3σ) are 5.7 ng/mL for ctDNA, 7.4 ng/mL for sDNA and 9.2 ng/mL for hsDNA, respectively. The method can be applied to determination of trace amounts of DNA.     

Resonance Rayleigh scattering study of the interaction of bleomycinA<Subscript>5</Subscript> with nucleic acids and its analytical application

The interaction of bleomycinA5 with nucleic acids has been investigated by using resonance Rayleigh scattering (RRS), molecular absorption and fluorescence spectra. The result shows that in near pH 2.2 buffer medium and absence of any metal ions, nucleic acids are capable of binding with bleomycinA5 (BLMA5) to form complexes which can remarkably enhance the RRS intensity and result in bathochromic and hyperchromic molecular absorption of nucleic acids and fluorescence quenching of bleomycinA5. The RRS spectral characteristics for the binding products of bleomycinA5 with various DNA and RNA are similar, and the maximum RRS peaks are at 301 nm for ctDNA and sDNA, 370 nm for hsDNA, 310 nm for RNAtypeVI and RNAtypeIII, respectively. The increments of RRS intensity are greatly different in which DNA enhances greatly and RNA enhances lightly. In this work, the optimum conditions of the interaction and some influencing factors have been investigated. The reaction mechanism and a binding model for the interaction of BLMA5 with the nucleic acids are discussed. In addition, a highly sensitive, simple and rapid new method for the determination of DNA has been developed. The detection limits (3σ) are 5.7 ng/mL for ctDNA, 7.4 ng/mL for sDNA and 9.2 ng/mL for hsDNA, respectively. The method can be applied to determination of trace amounts of DNA.     

功能性Cu-PVK纳米微球与核酸相互作用的共振光散射光谱及分析应用

在超声辐射下,H2O2氧化降解聚乙烯醇（PVA）,制得与Cu^2＋形成配位体的纳米尺寸的β-二酮型高分子微球（Cu-PVK）。对Cu-PVK的共振散射光（RLS）性质研究发现Cu-PVK与核酸形成缔合物时将导致Cu-PVK本身RLS信号急剧增加,基于此建立一种用RLS信号测定痕量核酸的新方法。方法的抗干扰能力强,已用于合成样品的分析。     

Resonance Rayleigh scattering study on the interaction of gold nanoparticles with berberine hydrochloride and its analytical application

A heavy metals enzymatic-based assay using papain was developed. Papain was assayed using the Casein-coomassie-dye-binding assay. The assay is sensitive to several heavy metals. The IC₅₀ (concentration of toxicant giving 50% inhibition) of Hg²⁺, Ag²⁺, Pb², Zn²⁺ is 0.39, 0.40, 2.16, 2.11 mg l⁻¹, respectively. For Cu²⁺ and Cd²⁺ the LOQ (limits of quantitation) is 0.004 and 0.1 mg l⁻¹, respectively. The IC₅₀ and LOQ values were found to be generally comparable to several other enzymatic and bioassays tests such as: immobilized urease, 15-min Microtox™, 48 h Daphnia magna, and 96 h Rainbow trout. The papain assay is xenobiotics tolerant, has a wide pH for optimum activity, is temperature stable, and has a relatively quick assay time. The papain assay was used to identify polluted water samples from industrial sources in Penang, Malaysia. We found one site where the assay gave a positive toxic response. The toxicity of the site was confirmed using Atomic Emission Spectrometry analysis.     

花菁-脱氧核糖核酸的共振光散射光谱及其分析应用

研究了一种苯并噻唑阳离子花菁与脱氧核糖核酸(DNA)作用的共振光散射光谱,在pH 6.0的六次甲基四胺-HCl缓冲介质中,痕量DNA的加入使花菁在590nm的共振光散射强度显著增强。在最佳实验条件下,增强的共振光散射强度与DNA浓度具有良好的线性关系,据此建立了一种测定DNA的共振光散射光谱法。方法的线性范围为:小牛胸腺DNA(CT DNA),0～20μg/mL,鱼精子DNA(FS DNA),0～15μg/mL;检出限分别为0.005μg/mL和0.008μg/mL。该方法已用于合成样品中DNA的测定。     

Resonance Rayleigh scattering spectral characteristics of interaction of nucleic acids with some cationic surfactants and their analytical applications

In near neutral medium, the resonance Rayleigh scattering (RRS) intensities of an alone cationic surfactant and nucleic acid are very weak. However, when they combine with each other to form a complex, the RRS intensity of the solution is enhanced greatly. In this paper the reactions of five cationic surfactants with nucleic acids have been studied. The results show that the reaction conditions and RRS spectral characteristics of these reactions are similar, but their sensitivities are obviously different. Among them, the sensitivity of cetyldimethyl benzylammonium chloride (CDBAC) with an aryl and large molecular weight is the highest, while that of cetyl-trimethylammonium bromide (CTAB) without aryl and with small molecular weight is the lowest. The detection limits for ctDNA and yRNA of the former are 6.6 and 29.4 ng · mL-1, while that of the latter are 13.3 and 53.6 ng · mL-1. The method has better selectivity and can be applied to the determination of trace amounts of nucleic acids. Furthermore, i     

Resonance Rayleigh scattering spectra, non-linear scattering spectra of tetracaine hydrochloride-erythrosin system and its analytical application

The interaction between erythrosine (ET) and tetracaine hydrochloride (TA) was studied by resonance Rayleigh scattering (RRS), frequency doubling scattering (FDS) and second-order scattering (SOS) combining with absorption spectrum. In a weak acidic medium of Britton-Robinson (BR) buffer solution of pH 4.5, erythrosine reacted with tetracaine hydrochloride to form 1:1 ion-association complex. As a result, the new spectra of RRS, SOS and FDS appeared and their intensities enhanced greatly. The maximum peaks of RRS, SOS and FDS were at 342 nm, 680 nm and 380 nm, respectively. The intensities of the three scattering were directly proportional to the concentration of TA in the range of 0.008-4.2 microg mL(-1) for RRS, 0.027-4.2 microg mL(-1) for SOS and 0.041-4.2 microg mL(-1) for FDS. The methods had very high sensitivities and good selectivities, and the detection limits were 0.003 microg mL(-1) for RRS, 0.008 microg mL(-1) for SOS and 0.012 microg mL(-1) for FDS, respectively. Therefore, a new method was developed to determinate trace amounts of TA. The recovery for the determination of TA in blood serum and urine samples was between 97.0% and 103.8%. In this study, mean polarizability was calculated by AM1 quantum chemistry method. In addition, the reasons for the enhancement of scattering spectra and the energy transfer between absorption, fluorescence and RRS were discussed.     

Resonance Rayleigh scattering study of interaction of heparin with some cationic surfactants and their analytical application

Binding of heparin with a cationic surfactant such as cetyldimethyl benzylammonium chloride (CDBAC), tetradecyldimethyl benzylammonium chloride (Zeph), cetylpyridinium bromide (CPB), tetradecane pyridinium bromide (TPB) and cetyltrimethylammonium bromide (CTAB) in a near-neutral medium can result in a significant enhancement of resonance Rayleigh scattering (RRS) intensities. The results showed that the reaction conditions and RRS spectral characteristics of these reactions are similar, but their sensitivities are obviously different. Among them, the sensitivity of CDBAC with an aryl and large molecular weight is the highest, while that of CTAB without aryl and with small molecular weight is the lowest. The detection limit for heparin of the former is 11 ng ml(-1) while that of the latter is 33 ng ml(-1). The method has better selectivity and was applied to the determination of trace amounts of heparin in sodium heparin injection samples with satisfactory results. Furthermore, it is discovered that the RRS intensity is related to the structure and molecular weight of the cationic surfactant.     

溴化十六烷基三甲铵存在下固红VR盐与fsDNA作用的共振光散射增强研究及其分析应用

研究了在阳离子表面活性剂溴化十六烷基三甲铵(CTMAB)存在下, 阴离子染料固红VR盐(FVR)和鱼精脱氧核糖核酸(fsDNA)作用的共振光散射(RLS)光谱特性、影响因素和最佳反应条件. 在pH 5.72和离子强度低于0.01 mol/L的条件下, fsDNA和CTMAB对FVR的共振光散射光谱有协同增强作用, 产生最大散射波长为361 nm的共振光散射增强(RLSE)信号. 在优化实验条件下, 测定fsDNA的线性范围为0.01～2.0 mg/L, 检出限可达2.5 μg/L. 方法能用于合成样中DNA的测定.     

Resonance Rayleigh scattering, frequency doubling scattering and second-order scattering spectra of the heparin-crystal violet system and their analytical application

In pH 6.0-11.2 Britton-Robinson buffer solution, binding of heparin with crystal violet (CV) can result in a significant enhancement of resonance Rayleigh scattering (RRS) and resonance non-linear scattering, such as frequency doubling scattering (FDS) and second-order scattering (SOS). Their maximum scattering wavelengths, λ_ex/λ_em, appear at 492 nm/492 nm for RRS, 984 nm/492 nm for FDS and 492 nm/984 nm for SOS, respectively. The optimum conditions of the reaction, the influencing factors and the relationship between the three scattering intensities and the concentration of heparin have been investigated. New methods for the determination of trace amounts of heparin based on the RRS, FDS and SOS methods have been developed. The methods exhibit high sensitivities, the detection limit for heparin is 2.9 ng ml⁻¹ for the RRS method, 3.5 ng ml⁻¹ for the FDS method and 3.3 ng ml⁻¹ for the SOS method. The methods have good selectivity and were applied to the determination of heparin in heparin sodium injection samples with satisfactory results.     

Resonance Rayleigh scattering spectrum for the chelate of lanthanum(III) with sodium tanshinon IIA silate and its analytical application

In a pH 3.6–5.0 HAc-NaAc buffer solution, when sodium tanshinon IIA silate (STSIIA) reacts with La(III) to form a chelate, the resonance Rayleigh scattering (RRS) intensity can be enhanced greatly and a new RRS spectrum will appear. The maximum RRS peak is located at 306 nm and the RRS intensity is proportional to the concentration of STSIIA in a certain range. The method is very sensitive and the detection limit for STSIIA (3σ/K) is 82.12 ng·mL⁻¹. The optimum reaction conditions and the effect of coexisting substances have been investigated. A new, simple and fast method for the determination of STSIIA based on RRS method is developed. It can be applied to the determination of STSIIA in the synthesis samples and Nuoxinkang injection. Combined with infrared absorption and NMR spectra, the structure of the chelate and the reasons of RRS enhancement are also discussed.     

Resonance Rayleigh scattering spectra, non-linear scattering spectra of malachite green-12-tungstophosphoric acid system and its analytical application in fish

In 0.1 molL(-1) (pH 1.0) HCl medium, 12-tungstophosphoric acid (TP) reacted with malachite green (MG) to form an ion-association complex. As a result, the new spectra of RRS, SOS and FDS appeared and their intensities were enhanced greatly. The maximum wavelengths of RRS, SOS and FDS were located at 334 nm, 586 nm and 330 nm, and the scattering intensities were proportional to the concentration of MG. Based on it a new method for the determination of MG has been established. The detection limits (3σ) of these methods were in the range of 3.7-27 ng mL(-1). The RRS, SOS, and FDS characteristics, absorption spectrum characteristics and optimum reaction conditions of the system were discussed. Effects of coexistent substances were tested, and the results demonstrated that this method had good selectivity. It has been applied to the determination of malachite green residues in fish flesh with satisfactory results. The reaction mechanism and reasons of RRS enhancement are discussed.     

Resonance Rayleigh scattering spectrum for the chelate of lanthanum(Ⅲ) with sodium tanshinon ⅡA silate and its analytical application

In a pH 3.6-5.0 Hac-NaAc buffer solution, when sodium tanshinon ⅡA silate (STSⅡA) reacts with La(Ⅲ) to form a chelate, the resonance Rayleigh scattering (RRS) intensity can be enhanced greatly and a new RRS spectrum will appear. The maximum RRS peak is located at 306 nm and the RRS intensity is proportional to the concentration of STSⅡA in a certain range. The method is very sensitive and the detection limit for STSⅡA (3σ/K) is 82.12 ng·mL-1. The optimum reaction conditions and the effect of coexisting substances have been investigated. A new, simple and fast method for the determination of STSⅡA based on RRS method is developed. It can be applied to the determination of STSⅡA in the synthesis samples and Nuoxinkang injection. Combined with infrared absorption and NMR spectra, the structure of the chelate and the reasons of RRS enhancement are also discussed.     

蛋白质-SDS-罗丹明B体系的共振光散射光谱及其分析应用

研究了阴离子表面活性剂十二烷基硫酸钠(SDS),阳离子染料罗丹明B,与蛋白质相互作用的共振光散射(RLS)光谱及用于蛋白质的测定.实验表明,在pH 4.35的酸性介质中,SDS的共振光散射强度较小,它与蛋白质结合后,共振光散射强度能得到增强,但加入阳离子染料罗丹明B后,共振光散射强度显著增强.在λ=332.0 nm处,ΔIRLS最大,并且增强的共振光散射信号与蛋白质的浓度成正比.据此建立了一种测定蛋白质的新方法,该方法灵敏度高,对HSA的检出限达到1.9 ng/mL,线性范围为0.01～5.0 μg/mL.用于人血清样品中蛋白质的测定,回收率为94.0%～105.5%.     

Resonance Rayleigh scattering spectra of Cu2+-adenine-WO4(2-) system and its analytical application

In pH 6.6-7.2 Tris-HCl buffer, Cu(2+) could react with adenine (A) to form a 1:1 coordination cation [CuA](2+), which only resulted in minor change of the absorption spectrum. However, when this cation further combined with WO(4)(2-) to form a 1:1 ternary ion-association complex [CuA]WO(4), the absorption spectrum changed a lot, and the resonance Rayleigh scattering (RRS), second-order scattering (SOS) and frequency doubling scattering (FDS) enhanced significantly. The maximum wavelengths of RRS, SOS and FDS were located at 310, 592 and 395 nm, respectively. The enhanced intensities of the three methods were proportional to the concentration of adenine in certain ranges, and the detection limit of the most sensitive RRS method was 7.4 × 10(-9) mol L(-1) (1.0 ng mL(-1)), indicating that this method could detect trace adenine. In this work, the optimum reaction conditions and the influencing factors have been studied, some potential interferences and the composition of the ion-association complex have been investigated. Meanwhile, the construction of the product and the reaction mechanism have been investigated by atomic force microscopy, transmission electron microscope and quantum chemical calculation. Accordingly, a novel RRS method for determination of adenine has been proposed and applied to detect adenine in real samples with satisfactory results.     

Resonance Rayleigh scattering, second-order scattering and frequency doubling scattering spectra for studying the interaction of erythrosine with Fe(phen)3(2+) and its analytical application

In a weak alkaline Britton-Robinson buffer medium, erythrosine (Ery) can react with Fe(phen)(3)(2+) to form 1:1 ion-association complex, which will cause not only the changes of the absorption spectra, but also the remarkable enhancement of resonance Rayleigh scattering (RRS), second-order scattering (SOS) and frequency doubling scattering (FDS) spectra, and the appearance of new spectra of RRS, SOS and FDS. The maximum RRS, SOS and FDS wavelengths (λ(ex)/λ(em)) of the ion-association complex are located at 358/358 nm, 290/580 nm and 780/390 nm, respectively. The increments of scattering intensities (ΔI) are directly proportional to the concentration of Ery in a certain range. The detection limits for Ery are 0.028 μg mL(-1) for RRS method, 0.068 μg mL(-1) for SOS method and 0.11 μg mL(-1) for FDS method, respectively. Among them, the RRS method has the highest sensitivity. Based on the above researches, a new highly sensitive and simple method for the determination of Ery has been developed. In this work, the spectral characteristics of absorption, RRS, SOS and FDS spectra, the optimum conditions of the reaction and influencing factors for the RRS, SOS and FDS intensities were investigated. In addition, the reaction mechanism was discussed.     

Resonance light scattering spectroscopy study of interaction between gold colloid and thiamazole and its analytical application

In this paper, we used resonance light scattering (RLS) spectroscopy to study the interaction between thiol-containing pharmaceutical-thiamazole and gold colloid. At pH 5.2, the resonance light scattering spectrum of gold nanoparticles has a maximum peak at 555 nm and the RLS intensity is enhanced by trace amount of thiamazole due to the interaction between thiamazole and gold colloid. The binding of colloidal gold to thiamazole results in ligand-induced aggregation of colloidal gold, which was characterized by RLS spectrum, ultraviolet-visible (UV-Vis) spectrum, and transmission electron microscopy (TEM). Based upon the study, we proposed a highly sensitive, gold colloid-based assay using RLS spectrum to detect pharmaceuticals for the first time. The mechanism of binding interaction between Au colloid and thiamazole was also discussed.     

四溴汞(Ⅱ)酸钾-异辛基苯二聚乙二醇醚二甲基苄基氯化铵的共振散射光谱及其分析应用

在pH2～8的溶液中,四溴汞（Ⅱ）酸钾和异辛基苯二聚乙二醇醚二甲基苄基氯化铵（BTC）反应生成离子缔合物,在390nm处有一共振散射峰,峰强度随汞（Ⅱ）质量浓度的增加而增大,据此建立了测定痕量汞的新方法。在实验条件下,此法测定汞（Ⅱ）的线性范围是14～240μg/L,检出限为μg/L,已用于合成水样和环境水样中汞（Ⅱ）的测定。     

中性红-8-羟基喹啉-亚硝酸根体系共振散射光谱研究及分析应用

NO2-与中性红在HCl介质中发生重氮化反应,生成的重氮盐在弱碱性溶液中与8-羟基喹啉发生偶联反应,偶联产物使得位于588 nm的共振散射光强度明显增强.基于该重氮化-偶联反应建立了共振散射光谱法测定NO2-的新方法.激光散射法测得样品中偶联反应产物的平均粒径为493 nm.方法的线性范围和检出限分别为0～480×10-6 g/L和8.9×10-6 g/L.方法用于蔬菜中NO2-的测定,回收率在95.9%～102.1%.     

Resonance light scattering spectroscopy study of interaction between norfloxacin and calf thymus DNA and its analytical application

The interaction between norfloxacin and calf thymus double-stranded DNA (dsDNA) has been studied by a resonance light scattering (RLS) technique with a common spectrofluorometer. The characteristics of RLS spectra, the effective factors and optimum conditions of the reaction have been investigated. In Britton-Robinson (BR) buffer (pH 5.87), norfloxacin has a maximum peak 405.5 nm and the RLS intensity is remarkably enhanced by trace amount of calf thymus dsDNA due to the interaction between norfloxacin and dsDNA. The binding of norfloxacin to DNA forms large particles, which were characterized by RLS spectrum, scanning electron microscopy (SEM), ultraviolet-visible (UV-vis) spectrum, and fluorescence spectrum. Based on the enhanced RLS intensity, a novel method for sensitive determination of calf thymus dsDNA concentration ranging from 0.02 to 2.3 microg ml(-1) was developed. The determination limit (3 sigma) was 1.2 ng ml(-1). The method is simple, rapid, practical and relatively free from interference generated by coexisting substance, as well as much more sensitive than most of the reported methods. Three synthetic samples of ctDNA were determined with satisfactory results.