罗丹明B-Mo(V)-SCN~--PVA体系荧光熄灭法测痕量钼

在聚乙烯醇存在下,用罗丹明B-Mo(V)-SCN~-荧光熄灭法测Mo,能消除过量的SCN-对罗丹明B的熄灭作用。加入聚乙烯醇后体系的荧光熄灭倍数比未加入时大14倍。此法灵敏度高、稳定性好、操作简便,检测下限0.12ng/ml Mo.可用于测水和头发中的钼。     

催化动力学荧光法测定痕量培氟沙星

研究了培氟沙星对铜(Ⅱ)催化过氧化氢氧化罗丹明B使其荧光猝灭的抑制作用,据此建立了催化动力学荧光分析法测定培氟沙星的新方法。在最佳实验条件下,方法线性范围为0.2~4.29μg/mL,检出限为0.2μg/L。对实际样品分析,平均回收率为97.6%~101.7%,相对标准偏差为1.03%~1.9%。     

荧光猝灭法测定痕量镉-四碘合镉-罗丹明S-聚乙稀醇荧光猝灭体系的研究

本文首次将罗丹明S应用于镉的荧光熄灭法测定,由于PVA-124的稳定作用,克服了罗丹明类试剂常须经萃取测定操作繁杂之不足。在加入各种试剂后,直接进行水相荧光测定。方法简便、灵敏,精密度好。     

Chemiluminescence determination of ultramicro DNA with a flow-injection method

A high sensitive flow-injection chemiluminescence method for determination of calf thymus DNA and herring sperm DNA has been developed. The method is based on the chemiluminescence reaction of Rhodamine B-cerium(IV)-thermally denatured DNAs in sulfuric acid media. The proposed procedure allows quantitation of DNAs in the range 2.6×10⁻⁵ to 0.26 μg ml⁻¹ for calf thymus DNA and 5.0×10⁻⁸ to 5.0×10⁻⁵ μg ml⁻¹ for herring sperm DNA with correlation coefficients 0.9998 and 0.9996 (both n=11), respectively. The detection limits (3σ) are 6.5×10⁻⁶ μg ml⁻¹ for calf thymus DNA and 4.3×10⁻⁸ μg ml⁻¹ for herring sperm DNA. The possible mechanism of chemiluminescence in the system is discussed.     

胶体金在DNA分子识别中的应用——胶体金对罗丹明B与单双链DNA识别作用的影响

通过研究罗丹明B与单双链DNA作用过程中，胶体金加入前后的紫外可见吸收光谱的变化，发现在胶体金加入的前后，罗丹明B均以沟槽方式与单双链DNA相作用；胶体金的加入可以较大程度地增大化合物与DNA之间的相互作用．     

Using sequential injection analysis for fast determination of phosphate in coastal waters

A sequential injection analysis system (SIA) is described which is suited for the fast determination of filterable molybdate reactive phosphate (FRP, 0.2 μm) in coastal waters. It processes up to 270 samples per hour with a detection limit (3σ) of 0.05 μM and is used for surface mapping of phosphate in areas with steep concentration gradients like the Wadden Sea. The determination is based on the reaction of phosphate with acidic molybdate to phosphomolybdate, which builds non-fluorescent ion pairs with rhodamine 6G. The remaining rhodamine fluorescence is detected at 550 nm with an excitation at 470 nm. Syringe pump, valve and detector were controlled by a self made python programme, which was optimised for high speed SIA measurements in monitoring applications.     

Use of the molybdenum-thiocyanate-rhodamine 6G ternary complex for spectrophotometric molybdenum determination without extraction

A modified thiocyanate method without extraction by using rhodamine 6G as a secondary ligand was developed. Molybdenum in 1.0×10⁻² M HCl, after the addition of ascorbic acid, was heated for 10 min in a 90 °C water bath for reduction. Suitable amounts of glycerine, Triton X-100, rhodamine 6G solutions and 2+1 (v/v) 9 M H₂SO₄+3 M KHSO₄ were added in this order. This solution was allowed to cool to room temperature and the absorbance at 570 nm was measured against a reagent blank 45 min after the addition of thiocyanate solution and the second aliquot of Triton X-100 solution. The complex was stable for at least 4 h, the order of reagent addition was important, and thiocyanate should be in large excess. Beer’s law was obeyed over the range 0.9×10⁻⁶ to 1.1×10⁻⁵ M Mo with the molar absorptivity being 1.1×10⁵ l mol⁻¹ cm⁻¹. The R.S.D. for the determination of 0.7 mg Mo l⁻¹ was 1.83% (n=8). Possible interferences of various cations and anions on molybdenum determination were studied. The proposed method was applied to the determination of molybdenum in a dental alloy, Wiron 99.     

罗丹明6G与核酸作用的共振光散射光谱及其分析应用

研究了罗丹明6G（Rh6G）与核酸（ctDNA和yRNA)作用的共振光散光谱（RLS）特征，基于RLS的增强，建立了一种测定核酸的新方法，考察了各种影响因素，在优化条件下确定了RLS强度与ctDNA和yRNA浓度之间的关系，相应的线性范围分别为0.05-37.0μg.mL^-1、0．1－10．0μg.mL^-1，检出限分别为3．0ng.mL^-1和9．5ng.mL^-1。四种合成样品五次平行测定结果的相对标准偏差（RSD）范围为2．0％－3．0％。     

Efficient degradation of dye pollutants using dioxygen mediated by iron(Ⅱ) 2,2''-bipyridine loaded layered clay catalyst under visible irradiation

The organic-inorganic layered solid catalyst Fe(bpy)32+-laponite was able to photodegrade Rhodamine B (RhB) by activation of dioxygen under visible irradiation (λ＞420 nm), while the homogeneous aqueous solution Fe(bpy)32+ showed no photoactivity. The catalyst could be repeatedly used and retained its reactivity. The hybrid catalyst could be separated from the suspension by centrifugation or sedimentation. The TOC removal yield of RhB was measured. Reactive oxygen species (ROS) formed during degradation was detected by EPR. A possible mechanism was proposed on the basis of the experimental results.