吖啶橙-罗丹明6G共振能量转移荧光猝灭法测定尿中1-羟基芘

建立了吖啶橙(AO)-罗丹明6G(R6G)共振能量转移荧光猝灭法测定尿中1-羟基芘的新方法.在λex/λem=470/556nm,十二烷基苯磺酸钠(SDBS)存在下,AO-R6G能够发生有效的能量转移,使R6G的荧光大大增强;1-羟基芘(1-OHP)的加入使R6G的荧光猝灭.方法的线性范围是21.3～982 μg/L;检出限为6.4 μg/L;平行7次测定相对标准偏差为0.98%～2.0%;回收率为96.0%～104.4%.该方法用于锅炉工尿样中1-羟基芘的测定,结果与常规的高效液相色谱法一致.     

吖啶橙-罗丹明6G能量转移荧光猝灭法定量测定茶多酚

在λex/λem=450/556 nm,十二烷基苯磺酸钠(DBS)存在下,吖啶橙(AO)-罗丹明6G(R6G)间能够发生有效的能量转移,使R6G荧光大大增强。酸性条件下,茶多酚的加入使体系R6G的荧光发生猝灭。利用AO-R6G能量转移荧光猝灭法定量测定茶多酚,提高了测定的灵敏度和选择性。茶多酚含量在0.75~60mg/L范围内与R6G荧光猝灭程度呈良好线性关系,方法检出限为0.35 mg/L。6次平行测定样品相对标准偏差1.36%~2.17%,回收率为93%~107%。该方法用于茶叶样品中茶多酚含量的测定,结果满意。     

新荧光试剂5—（4—羧基苯偶氮）—8—水杨醛缩氨基喹啉荧光增敏法测定人血清蛋白质

合成了新荧光试剂5-(4-羧基苯偶氮)-8-水杨醛缩氨基喹啉(p-CPSAQ)，探讨了与人血清蛋白反应的最佳实验条件。在pH=7．0的缓冲体系中，蛋白质的存在使p-CPSAQ的荧光大大增强，据此建立了测定人血清蛋白质的灵敏方法；对人血清白蛋白和γ-球蛋白的线性范围分别为0．1—4．5mg／L和0．1—4．0mg／L；检出限分别为0．028和0．027mg／L。方法灵敏、快速、选择性好，用于人血清样品中总蛋白的测定，结果满意。     

能量转移荧光猝灭法测定加替沙星

在λ_(ex)/λ_(em)=470/566 nm、BR缓冲溶液(pH=5.72)、十二烷基苯磺酸钠介质中,吖啶橙(AO)与罗丹明6G(R6G)间能发生有效的能量转移,使R6G的荧光强度显著增强;加替沙星的加入,使R6G的荧光发生猝灭.应用AO-R6G能量转移荧光猝灭法测定加替沙星含量,提高了测定的灵敏度和选择性.加替沙星的浓度在0.6～9.0 μmol·L~(-1)范围内与R6G荧光猝灭程度呈线性关系;方法检出限为0.52 μmol·L~(-1);平行6次测定样品相对标准偏差为0.62%～0.84%;回收率为90.0%～105%.常见金属离子及药物敷料对测定无干扰,不经分离直接用于药物中加替沙星的测定.     

荧光红-曙红Y能量转移及荧光猝灭法测定痕量铜(Ⅱ)的研究

在λex／λem=404．7／550nm,乳化剂OP存在下,荧光红-曙红Y能够发生有效能量转移,使曙红Y荧光强度大大提高;在pH6．5～7．6的KH2PO4-NaOH缓冲溶液中,Cu(Ⅱ)与曙红Y和邻菲罗啉形成配合物,使曙红Y的荧光猝灭,从而建立了测定痕量铜的荧光分析新方法。铜含量在0～250μg／L范围内与曙红Y的荧光猝灭程度呈良好的线性关系。方法的检出限为0．82μg／L;测定100μg／L铜溶液,其RSD为4．6％(n=11);样品加标回收率为102．1％～105％。本法用于人发、茶叶和大米中痕量铜的测定,结果满意。     

顺序注射可更新表面固相荧光免疫法测定人血清中免疫球蛋白G

建立了采用芯片式微型流通池的测定人血清中免疫球蛋白G(IgG)的顺序注射可更新表面非均相荧光免疫分析法。将羊抗人IgG抗体固定于包被有蛋白A的Sephamse CL4B凝胶微珠,然后制备成固相抗体。用标记FITC的抗人IgG抗体作为第二抗体。固相抗体、血清试样和荧光标记第二抗体由顺序注射系统注入芯片式微型流通池,并在其中进行免疫反应生成夹心式抗体．抗原荧光复合物。荧光分光光度计通过光纤与流通池耦合测定截留于流通池中的抗体一抗原复合物荧光强度。一次测定完成后,微珠即被排出流通池。流通池经缓冲液清洗后即可进行下一次测定。体系经优化后,检出限为0．1mg／L IgG,分析速率达到11次／h。3．9mg／L IgG的日内和日间精密度(RSD)分别为1．7％和5．2％;校正曲线的线性范围为0．3—7．0mg／L IgG。所建立的方法已成功地应用于人血清中IgG的测定。     

吖啶橙-罗丹明6G能量转移荧光法测定痕量磷

在λex/λem=450/556nm,十二烷基苯磺酸钠(DBS)存在下,吖啶橙-罗丹明6G能够能有效能量转移,使罗丹明6G荧光大大增强,酸性条件下,正酸根与钼酸钼反应生成磷钼酸,磷钼酸与R6G形成离子缔合物,使R6G的光猝来利用吖淀橙-罗丹明6G能量转变荧光法测定痕量磷,提高了测定磷的灵敏度和选择性,磷含量的0.05~0.70μg/L 范围内与罗丹明6G的荧光猝程度呈良好的线性关系.最低检出限为5ng/L,回收率为95%~110%,测定0.50μg/L,磷溶液,相对标偏差为6%,该法用于水样及土壤中的活性磷的测量,结果满意.     

四羧基镍酞菁共振散射法测定蛋白质

建立了一种测定蛋白质的新方法．在pH3．6的Britton-Robinson（B-R）缓冲溶液中,蛋白质与四羧基镍酞菁NiPc（COOH）4发生相互作用,使体系在λ=388nm处的共振散射（RLS）增强,并且增强的散射强度（IRLS）与蛋白质的含量成比例,据此利用四羧基镍酞菁NiPc（COOH）4为光谱探针共振散射法测定人血清中的总蛋白质,同时优化了体系光散射检测的实验参数．在最佳的实验条件下,对牛血清白蛋白（BSA）、人血清白蛋白（HSA）、人血清总蛋白（TP）的线性范围分别为0．00～1．20mg／L、0．00～1．00mg／L、0．00～1．00mg／L,相应检测限分别为5．97×10^-4mg／L、2．90×10^-4mg／L、4．76×10^-4mg／L．将该方法应用于实际人血清样品中总蛋白的测定,结果与考马斯亮蓝法比较,令人满意．     

新荧光增敏法测定人血清蛋白质

合成了新荧光试剂5-(4-羧基苯偶氮)-8-水杨醛缩氨基喹啉(p-CPSAQ),探讨了与人血清蛋白反应的最佳实验条件.在pH=7.0的缓冲体系中,蛋白质的存在使p-CPSAQ的荧光大大增强,据此建立了测定人血清蛋白质的灵敏方法;对人血清白蛋白和γ-球蛋白的线性范围分别为0.1～4.5 mg/L和 0.1～4.0 mg/L;检出限分别为0.028和0.027 mg/L.方法灵敏、快速、选择性好,用于人血清样品中总蛋白的测定,结果满意.     

耐尔蓝-十二烷基苯磺酸钠-蛋白质体系的荧光反应及其分析应用

研究了耐尔蓝-十二烷基苯磺酸钠体系的吸收光谱和荧光光谱特性，并以此体系建立了测定蛋白质的新型荧光探针。在优化实验条件下，对人血清白蛋白和γ-球蛋白测定的线性范围均为0．16mg/L，检出限分别为0．020mg/L和0．036mg/L。该方法用于人血清中总蛋白含量的测定，与临床测定结果相吻合。     

Fluorescence resonance energy transfer between acridine orange and rhodamine 6G and its analytical application for vitamin B12 with flow-injection laser-induced fluorescence detection

By coupling flow-injection with laser-induced fluorescence detection, a setup was developed and a novel method combining fluorescence resonance energy transfer (FRET) and flow-injection analysis (FIA) was proposed for the determination of vitamin B₁₂ (VB₁₂) based on its fluorescence quenching on the system of acridine orange (AO)/rhodamine 6G (R6G). The effective energy transfer could occur between AO and R6G in the dodecyl benzene sodium sulfonate (DBS) while 454 nm argon laser was used as the excitation source, and as a result, the fluorescence emission of R6G has been increased significantly. It was found that the fluorescence of the above system could be sharply diminished by VB₁₂. By using the mixed solution AO-R6G-DBS and the same solution containing VB₁₂ as the carrier and sample, respectively, a series of negative peaks which could be applied for the quantification of VB₁₂ were obtained. The detection limit for VB₁₂ was 1.65 × 10⁻⁶ mol/L. The linear range for determining VB₁₂ was 4 × 10⁻⁴ to 2 × 10⁻⁶ mol/L (correlation coefficient, r = 0.9923). The method was applied to measure VB₁₂ injections with satisfactory results.     

CdTe量子点-罗丹明6G荧光共振能量转移体系的构建及其应用研究

采用巯基化合物修饰的CdTe量子点构建了量子点(供体)-罗丹明6G(受体)荧光共振能量转移体系, 研究了CdTe量子点与牛血清白蛋白(BSA)的相互作用. 结果表明, CdTe量子点与BSA相互作用后提高了CdTe量子点-罗丹明6G 体系的荧光共振能量转移(FRET)效率, 减小了CdTe量子点和罗丹明6G分子间的距离(r), 证实BSA是通过其色氨酸(Trp)残基与CdTe量子点表面金属发生配位作用而直接结合到量子点表面的.     

荧光素-曙红Y能量转移荧光猝灭法测定微量白蛋白研究

在λex/λem=405/547 nm,于缓冲溶液和表面活性剂存在的情况下,荧光素和曙红Y能够发生有效能量转移,而牛血清白蛋白(BSA)的加入使得曙红Y荧光猝灭,该体系可用于微量蛋白质的测定。系统探讨了荧光素-曙红Y能量转移体系发生荧光猝灭的条件,最佳条件为:2.0 mL pH=3.8的B-R缓冲溶液,0.4 mL 0.05%曲拉通X-100,1.5 mL 1.0×10-4mol/L的荧光素水溶液,2.0 mL 1.0×10-4mol/L的曙红Y水溶液,最佳实验时间为溶液配制完成静置15 min后60 min内,最佳加入顺序为pH=3.8缓冲溶液+荧光素+曙红Y+曲拉通+蛋白质标准溶液或样品。在优化的实验条件下,蛋白质含量在0～2.0μg/mL范围内与荧光猝灭强度呈良好的线性关系。检出限为6.6 ng/mL;测定样品的相对标准偏差(RSD)在±5%以内;样品加标回收率为90.4%～95.3%。该法可用于人血清、牛奶中蛋白质含量的测定。     

CdTe量子点与罗丹明6G间的荧光共振能量转移机理研究

本文在合成水溶性巯基乙酸修饰的CdTe量子点的基础上,研究了CdTe量子点与罗丹明6G之间的荧光共振能量转移.实验结果表明:构建的CdTe量子点(供体)-罗丹明6G(受体)荧光共振能量转移体系在磷酸盐缓冲溶液中有较好的转移效果.当磷酸缓冲溶液pH值为7.4,NaCl浓度为1.0 mol/L时,构建的CdTe量子点-罗丹...     

How Graphene Oxide Quenches Fluorescence of Rhodamine 6G

We investigate the fluorescence quenching of Rhodamine 6G (R6G), a well known laser dye with a high fluorescence quantum yield, by as-synthesized graphene oxide (GO) in aqueous solution, which is found to be rather efficient. By means of steady-state and time-resolved fluorescence spectroscopy combined with detailed analysis about the linear absorption variation for this R6G-GO system, the pertinent quenching mechanism has been elucidated to be a combination of dynamic and static quenching. Possible ground-state complexes between R6G and GO during the static quenching have also been suggested. Furthermore, the direction of photoinduced electron transfer between R6G and GO has been discussed.     

岩白菜素与牛血清蛋白相互作用的荧光光谱研究

应用荧光光谱研究了岩白菜素与牛血清白蛋白(BSA)分子间的相互作用.结果表明,岩白菜素对BSA内源荧光的猝灭机制属于形成化合物所引起的静态猝灭,猝灭常数Ksv为1.905×104L.mol-1;岩白菜素与BSA反应的结合常数为2.083×104,结合位点数为1.由热力学参数确定了岩白菜素与牛血清白蛋白的结合作用主要为静电作用.实验还发现随着岩白菜素的加入,BSA的猝灭值与岩白菜素浓度在1.5×10-5~1.5×10-4mol.L-1的范围内呈良好的线性关系,检出限2.0×10-6mol.L-1,可用于岩白菜素的测定.     

荧光光谱法研究茶碱与牛血清白蛋白的相互作用

荧光光谱法研究茶碱与牛血清白蛋白的相互作用;茶碱;牛血清白蛋白;荧光猝灭;能量转移     

Mechanistic Insights into the Fluorescence Quenching of Rhodamine 6G by Graphene Oxide

The fluorescence quenching of Rhodamine 6G (R6G) by graphene oxide (GO) was interrogated by R6G fluorescence measurements using a set of controlled GO samples with varied C/O ratios as the quencher.The carbonyl groups on the GO nanosheet turned to play a dominant role in quenching the R6G fluorescence.The quenching in the static regime can be described by the "sphere of action" model.The significant absorption of the R6G fluorescence by the ground-state complex formed between R6G and GO was identified to be responsible for the static quenching.This work offers helpful insights into the fluorescence quenching mechanisms in the R6G/GO system.     

Investigation of the interaction between acridine orange and bovine serum albumin

The results from the measurement of the fluorescence spectrum showing the binding characteristics of acridine orange (AO) and bovine serum albumin (BSA) are reported. It was found that the equilibrium constant k=4848.64 l mol⁻¹, and the number of binding sites n=0.82. Based on the mechanism of the Forster energy transference, the transfer efficiency of energy and distance between the acceptor AO and BSA were found. The interaction between AO and BSA have been verified as consistent with the static quenching procedure and the quenching mechanism is related to the energy transfer.