A Selective and Sensitive Fluorescence Probe for Se(Ⅳ) Based on Fluorescence Quenching of Gatifloxacin

A novel high selective and sensitive fluorescence probe termed gatifloxacin was discovered based on fluorescence "on-off" phenomenon in the presence of Se(Ⅳ). In the Tris-HCl/acetonitrile(3:7, volume ratio, Tris-HCl 0.05 mol/L, pH=7.3) sys-tem, the fluorescence intensity of gatifloxacin was linearly decreased with the concentration increase of Se(Ⅳ) in a range of 1.0×10^-5-5.0×10^-5 mol/L with a correlation coefficient of 0.9979(R²=0.9958) and in a range of 5.0×10^-5-1.0×10^-4 mol/L with a correlation coefficient of 0.9973(R²=0.9946). The detection limit of Se(Ⅳ) was 1.70×10^-6 mol/L.     

Electroanalysis and simultaneous determination of dopamine and epinephrine at poly(isonicotinic acid)-modified carbon paste electrode in the presence of ascorbic acid

A carbon paste electrode modified with electropolymerized fills of isonicotinic acid was developed.The modified electrode shows excellent electrocatalytic activity toward the oxidation of both dopamine(DA)and epinephrine(EP).Separation of the reduction peak potentials for dopamine and epinephrine was about 357 mV in pH 5.3 phosphate buffer solution(PBS)and the character was used for the detection DA and EP simultaneously.The peak currents increase linearly with DA and EP concentration over the range of 8.0×10-5 to 7.0×10-4 mol/L and 5.0×10-6 to 1.0×10-4 mol/L with detection limits of 2 × 10-5 and 1×10-6 mol/L,respectively.The interference studies showed that the modified electrode exhibits excellent selectivity in the presence of large excess of ascorbic acid(AA).     

Application of 2,2'-dithiobis(4-methylthiazole) as sensing material for construction of Lu~(3+) PVC-membrane sensor

In this work a new Lu³⁺ PVC-membrane sensor based on 2,2’-dithiobis（4-methylthiazole）（TMT） has been fabricated.The sensor exhibits a Nernstian slope of 19.6±0.4 mV decade（?） in the concentration range of 1.0×10⁶-1.0×10² mol L¹ and a detection limit of 6.8×10⁷ mol L¹.It could work well in the pH range of 2.7-9.6.The selectivity of the sensor against a lot of common alkaline,alkaline earth,transition,heavy metals and specially lanthanide ions was very good.     

一种新型比色荧光双通道水相检测氰根离子的化学传感器

合成了一种新型的,能在含水介质中比色荧光双通道单一选择性识别CN^-的传感器分子1-羟基萘甲叉酰肼乙基-3-羟基萘甲叉酰肼甲基苯并咪唑溴鎓盐(J1)。 在J1的DMSO/H₂O (体积比3:2)HEPES 的缓冲体系(pH=7.2)中分别加入F^-、Cl^-、Br^-、I^-、AcO^-、HSO₄^-、ClO₄^-、H₂PO₄^-、SCN^-和CN^-等阴离子后,只有CN^-的加入会使得溶液颜色发生明显的变化,由无色变为深黄色。 相应地在J1的DMSO/H₂O (体积比4:1)HEPES的缓冲体系(pH=7.2)中加入CN^-,溶液发出明亮的黄色荧光。 这一识别过程,不会受到其它阴离子的干扰。 紫外-可见光谱的最低检测限为1.57×10^-7 mol/L,检测线性范围为3.875×10^-4~2.15×10^-2 mol/L。 荧光光谱的最低检测限为4.63×10^-6 mol/L,检测线性范围为0.8×10^-4~1.60×10^-3 mol/L。 此结果表明,J1是一种良好的用于识别 CN^-的化学传感器,在含水介质中对CN^-具有选择性好、灵敏度高以及抗干扰性强的识别性能。 与此同时,基于J1对于CN^-的高选择性识别我们制备了CN^-的检测试纸,该试纸能够方便、快捷、准确地检测水中的CN^-。     

Thiocyanate ion selective electrode based on bis(N-3-methylphenyl salicylidenaminato)copper(Ⅱ) ionophore

In this work a PVC membrane electrode based on bis(N-3-methyl phenyl salicylidenaminato)copper(II)as ionophore was prepared.The electrode was tested by inorganic anions and showed good selectivity for thiocyanate ion.This sensor showed Nerstian behavior with a slope of a-59.3 mV per decade at 25℃.The proposed electrode exhibited a wide linear range from 1.0 × 10~(-6) mol/L to 1.0× 10~(-1) mol/L with a detection limit of 5.0×10~(-7) mol/L.The electrode response was independent of pH in the range of 4.0-10.0.The response time is about 9-21s,and the electrode can be used for over 60 days without considerable deterioration.The prepared sensor was applied as an indicator electrode in potentiometric titration of SCN with Ag~+ ion and to determine the thiocyanate in samples of urine and saliva.     

FRET-based ratiometric fluorescent detection of arginine in mitochondrion with a hybrid nanoprobe

A ratiometric fluorescent hybrid nanoprobe CDs-1 for arginine(Arg),exhibiting high sensitivity(the limit of detection,LOD,being 6.5×10^-8 mol/L) and excellent selectivity and anti-interference ability,was fabricated through fluorescence resonance energy transfer(FRET) and the electrostatic attraction between positively-charged hemicyanine molecules and negatively-charged carbon dots(CDs).Arg can be quantitatively detected in the concentration range from 6.0×10^-5 mol/L to 2.7×10^-4 mol/L.Further,due to its ability to target mitochondrion and low cytotoxicity,intracellular Arg was succes s fully tracked through ratiometric fluorescence imaging.     

A supramolecular fluorescent probe based on cucurbit[10]uril for sensing the pesticide dodine

We report herein a new fluorescent probe for the selective recognition and determination of dodine among 20 different pesticides.This fluorescent probe was assembled through host-guest complexation between cucurbit[10]uril(Q[10]) and aminopropyl-1-pyrenebutanamide(PBA) and is designated as PBA@Q[10].Addition of dodine to PBA@Q[10] results in a dramatic enhancement of fluorescence intensity at 390 nm,accompanied by fluorescence quenching at 488 nm.On this basis,the detection limit is 6.78 × 10^-7 mol/L.The response mechanism is a competitive interaction:dodine occupies the cavity of Q[10] and forces PBA to leave.     

铕-四环素-TOPO-十二烷基磺酸钠荧光体系及四环素测定的研究

广谱抗菌素四环素是一种亲癌化合物,近年来已成为诊断、治疗肿瘤的一种重要的荧光探针,并用于临床检查和治疗中。已报道的检测四环素的极谱、比色、色谱、紫外分光光度、荧光和微生物等法大多复杂且费时。而四环素能与Eu~(3+)形成稳定螯合物,且四环素-Eu~(3+)-TOPO-十二烷基磺酸钠多元络合物体系能发射很强的Eu~(3+)的特征荧光,所以我们提出了用上述多元络合物荧光体系来检测四环素的新的荧光方法,并将该法用于人体血清和尿中四环素的测定。结果表明,该法的检出限为1.2×10~(-8)mol/L,比Eu~(3+)-四环素二元荧光体系的灵敏度约提高两个数量级,且具有简便、快速等特点。     

Flow Injection Chemiluminescence Method for Nalbuphine Hydrochloride in Pharmaceutical Formulations Using Tris(2,2'-bipyridyl)ruthenium(II) Chloride-diperiodatocuprate(III) Reaction

Asensitive and selective method employing chemiluminescence(CL) coupled with flow injection(FI) is reported for nalbuphine hydrochloride(NAL) assay in pharmaceutical formulations. The enhancement effect of NAL on the CL reaction between tris(2,2'-bipyridyl)ruthenium(II) chloride-diperiodatocuprate(III) {Ru[(bpy)₃]²⁺-Cu(III) complex} in acidic medium is used as analytical measurement. The optimal conditions of the CL reaction were sulfuric acid 1.0×10^-3 mol/L, Ru[(bpy)₃]²⁺ 7.5×10^-5 mol/L, Cu(III)/Ag(III) complexes 4.0×10^-4/5.0×10^-4 mol/L, sample loop volume of 120 μL and flow rate of 2.5 mL/min. The sensitivities of the method in terms of detection(S/N=3) and quantification(S/N=10) limits are 5×10^-4 and 0.001 ppm(1 ppm=1 mg/L), respectively. The linear response of the instrument in the form of CL intensity with respect to NAL concentration is over the range 0.001-15.0 ppm(R²=0.9999) with relative standard deviation from 0.8% to 3.2% and injection throughput of 120 injection/h. The applications of the method include the quantitative analysis of NAL in pharmaceutical injection samples. Variations and the average results of the proposed method are not signi-ficantly different from the results of a reported method by applying F- and paired student t-test. The most likely CL reaction mechanism is written in accordance with spectrophotometric and CL studies.     

Facile synthesis of enzyme functional metal-organic framework for colorimetric detecting H2O2 and ascorbic acid

In this work,a metal-organic frameworks material MIL-88 was prepared easily using solvent-thermal method,and was first found to have catalytic activities similar to those of biological enzymes such as catalase and peroxidase.The material was characterized by XRD,SEM,TEM,EDX,FT-IR techniques and an N_2 adsorption method.It exhibited peroxidase-like activity through catalytic oxidation of the peroxidase substrate 3,3',5,5'-tetramethylbenzidine(TMB) in the presence of H_2O_2,producing a blue-colored solution.Under optimal conditions,the absorbance at 652 nm is linearly correlated with the concentration of H_2O_2 from 2.0×10~(-6) mol/L to 2.03×10~(-5) mol/L(R~2=0.981) with a detection limit of 5.62×10~(-7) mol/L(S/N=3).More importantly,a sensitive and selective method for ascorbic acid detection was developed using this material as a catalyst.The analytical method for ascorbic acid detection was observed to have a linear range from 2.57×10~(-6) mol/L to 1.01×10~(-5) mol/L(R~2=0.989) with a detection limit of 1.03×10~(-6) mol/L(S/N=3).This work suggests MOFs have advantages of preparing biomimetic catalysts and extends applications of the functional MOFs in the field of biosensor.     

四环素-Al(Ⅲ)配合物与DNA的相互作用研究

研究了四环素(TC)-Al³⁺配合物与DNA的相互作用.吸收光谱和荧光光谱研究表明,TC与DNA无明显的相互作用,但在Al³⁺离子存在下,TC能结合到小牛胸腺DNA上.TC先与Al³⁺作用,生成TC-Al二元配合物,该配合物再与DNA发生作用,形成(TC-Al)-DNA三元配合物.TC-Al二元配合物与DNA的结合常数为6.5×10⁴L/mol,其配位比n(TC):n(Al):n(DNA)=1:1:1.TC-Al配合物与DNA的键合模式主要是静电相互作用.溶液的pH值对TC-Al二元配合物和(TC-Al)-DNA三元配合物的形成有一定的影响.利用TC-Al配合物与DNA作用使体系荧光强度增强的性质测定DNA,其线性范围为1.0×10^-6～6.0×10^-5mol/L,检测限为5.0×10^-7mol/L.分别测定了天然与热变性酵母样品中DNA的含量,结果令人满意.     

可视化检测次氯酸的苯并咪唑类 荧光增强型探针

合成了一种新型的苯并咪唑类荧光增强型探针2-{[4-(1H-苯并咪唑-2-基)苯亚甲基]氨基}-3-氨基马来腈(ZY12), 用光谱方法研究了其对次氯酸的识别作用. 实验结果表明, ZY12对ClO ^-表现出较高的选择性和灵敏度, 且响应快速, 抗干扰能力强; 将ClO ^-加入到ZY12溶液中后, 反应体系的荧光强度随ClO ^-浓度的增加而逐渐增强, 并伴随着荧光颜色由微蓝色到亮蓝色的变化, 可实现对ClO ^-的可视化检测; 在1.8×10 ^-6~3.4×10 ^-5 mol/L浓度范围内, ZY12能够定量检测ClO ^-, 检测限为2.8×10 ^-7 mol/L; ZY12可应用于不同水样中ClO ^-的检测, 并能对HeLa活细胞中的ClO ^-进行荧光成像.     

A Study of Fluorescence System of Eu-Chlorotetracycline-Benzoylacetone-CTMAB Multibasic Complex

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同步-导数-化学除氧微乳状液增稳室温磷光法测定痕量荧蒽与屈的研究

同步－导数－化学除氧微乳状液增稳室温磷光法测定痕量荧蒽与屈的研究杨欣,董川,晋卫军,魏雁声,刘长松（山西大学化学系,大原,０３０００６）关键词同步－导致－化学除氧微乳液增稳室温磷光法,荧蒽,屈Ｒａｍｏｓ等［１］于１９８８年提出了微乳状液增稳室温磷光法...     

Determination of L-phenylalanine by cucurbit[7]uril sensitized fluorescence quenching method

The determination method of L-phenylalanine（LPA） by fluorescence quenching was developed.The assay was based on the combination of the cucurbit[7]uril（CB[7]） with palmatine hydrochloride（PAL） reaction.In the presence of CB[7],the fluorescence of PAL was quenched by LPA which can be employed to detect LPA.Under the optimal conditions,a linear range 3.63×10^-8- 9.68×10^-6mol/L and a detection limit 1.27×10^-8mol/L of LPA were obtained.The relative standard deviation（R.S.D） was 1.8%obtained from a series of 11 standards each containing 6.05×10^-6 mol/L of LPA.This paper also discusses the mechanism of fluorescence indicator probe.     

多环芳烃芴、苊的无保护流体室温磷光性质研究

我们[1,2 ]曾报道丹磺酰氯及其衍生物在无保护性介质亦无有机溶剂存在的水溶液中能诱导出强而稳定的室温磷光 (ＲＴＰ) ,并命名为ＮＰ ＲＴＰ[37].此后 ,Ｃａｒｒｅｔｅｒｏ等[810 ]亦发现了萘唑啉、萘氧乙酸和苊溶液在无任何有序介质时的ＲＴＰ发射现象 .在已有的研究中至少有两个问题需进一步探索 :其一 ,除苊外 ,已实现ＮＰ ＲＴＰ发射的化合物都仅具双环结构 ,即萘系化合物 ,对于多环化合物是否有类似的发射特性和随环的增多是否会出现新的特性 ;其二 ,对于无水溶性取代基的多环芳烃 ,因其在水中的溶解度很小 ,所引入的有机溶剂的种类和…     

化学发光新体系NaIO4-H2O2-痕量环己烷-多羟基酚的研究及其应用

近年来,一些无机氧化剂在氧化有机物时伴随的化学发光现象引起了分析工作者的广泛兴趣[1,2].NaIO4氧化H2O2会产生弱化学发光,不同的多羟基酚类物质能不同程度地增强这一化学发光行为,据此建立了测定多羟基酚的化学发光法.目前,利用该法测定的酚主要有苯酚[3]、酚的衍生物[4]和连苯三酚[5,6].本文建立的测定连苯三酚的方法检测限较王伦等[3]的利用苯酚对Luminol-H2O2发光体系猝灭作用测定工业废水及Ermiridis[5]以IO4-在碱性介质中直接氧化连苯三酚的检测限低两个数量级,且扩大了测定酚的种类.研究发现,一些非极性有机溶剂对这一化学发光亦有增强和增稳作用,而痕量非极性溶剂由于在水中的溶解性较差,对化学发光的作用尚未受到注意.     

Thin-layered MoS2/polyaniline nanocomposite for highly sensitive electrochemical detection of chloramphenicol

In this study, we synthesized molybdenum disulfide/polyaniline (MoS₂/PANI) nanocomposite via in situ polymerization of aniline in the presence of thin-layered MoS₂. The as-prepared MoS₂/PANI nanocomposite obtained an improved electrochemical performance due to the physisorption interaction between aromatic aniline and the basal plane of MoS₂. Furthermore, we constructed a new kind of electrochemical sensor based on MoS₂/PANI nanocomposite for the detection of chloramphenicol, which showed an excellent performance. The sensor has a high sensitivity and wide detection range from 1×10^-7 mol/L to 1×10^-4 mol/L, with a low detection limit of 6.9×10^-8 mol/L.     

壳聚糖与茜素红相互作用的电化学研究

生物活性大分子蛋白质、DNA及多糖等与小分子探针间的相互作用及其机理是近年来化学、临床医学及生命科学中研究的热点之一,这些研究可用于生物大分子的检测和新药的研发,壳聚糖(CS)是目前自然界已被发现的唯一带正电荷的可食用的碱性多糖,分子中含有丰富的氨基和羟基,并具有双螺旋结构,近年来已在食品、医药保健、化妆、环保、农业及化学化工等领域得到广泛应用,     

基于金纳米簇探针的荧光猝灭检测铁离子

以D-色氨酸为保护剂和还原剂, 采用水热法快速制备了具有强荧光的金纳米簇(D-Trp@AuNCs); 以其作为荧光探针, 建立了基于荧光猝灭的选择性高灵敏检测Fe³⁺的传感方法. 利用透射电子显微镜(TEM)、 紫外-可见光谱(UV-Vis)和红外光谱(IR)等手段对制备的金纳米簇进行了表征, 并利用荧光光谱研究了D-Trp@AuNCs的荧光性能. 结果表明, D-Trp@AuNCs具有较好的生物相容性, 其最大激发波长为370 nm, 最大发射波长为460 nm; 向金纳米簇溶液中加入Fe³⁺后, D-Trp@AuNCs的荧光发生明显猝灭, 其猝灭程度与Fe³⁺的浓度在0.3~500.0 μmol/L范围内呈现良好的线性关系, 检出限为33.1 nmol/L(S/N=3). 将该荧光探针用于实际水样中Fe³⁺的检测, 回收率为86.6%~106.5%.