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1.
韩爱霞  常瑞  牛丽红  张复实 《分析化学》2004,32(8):1123-1123
过氧化物酶(POD)由于活性高和选择性好常用于H202和葡萄糖(Glucose)含量的测定,但天然POD价格昂贵、易失活,实验条件和储存环境都很苛刻。肌红蛋白(Mb)是一种生物小分子,价格比POD低,实验条件温和,本实验将肌红蛋白作为过氧化物酶模拟酶催化H202氧化偶联还原型色原N-乙基-N-(2-羟基-3-磺酸基丙基)-3,5-二甲氧基苯胺(DAOS)和4-氨基安替比林(AAP)显色反应能用于H202的测定,  相似文献   

2.
单自兴  卢国坚 《有机化学》2004,24(4):325-327
报告多官能团化合物苏—(1S,2S)—2—(N,N-二甲胺基)—1—(对硝基苯基)—1,3—丙二醇与聚合物支载条件下的溴试剂发生的—种新的选择性N-甲基氧化为N-甲酰基的反应.在Na2HPO4存在下,苏—(1S,2S)—2—(N,N-二甲胺基)—1—(对硝基苯基)—1,3.丙二醇于水—CCL4体系中被717阴离子交换树脂支载的溴在60℃氧化24h给出51%收率的苏—(1S,2S)—2—(N-甲基—N—甲酰胺基)—1—(对硝基苯基)-1,3-丙二醇.这种选择性N—甲基氧化为N-甲酰基的反应在2—氨基—1,3—丙二醇衍生物化学中是第—次观察到.  相似文献   

3.
报道了新显色剂 1-(4-硝基苯)-3-(3-甲基吡啶)-三氮烯(NPMPDT)的合成及其与铜的显色反应.在OP的存在下,pH 10.5的Na2B4O7-NaOH缓冲溶液中,该试剂能与铜发生显色反应,铜与NPMPDT形成摩尔比为2∶1型的黄色配合物,在460 nm处有一最大正吸收,在535 nm 处有一最大负吸收.以460 nm为参比波长,535 nm为测量波长进行双波长测定,其表观摩尔吸光系数ε=2.18×105 L·mol-1·cm-1,铜的质量浓度在0~0.48 μg/mL 范围内符合比尔定律,用本法测定大米和面粉中微量的铜,结果满意.  相似文献   

4.
为建立一种快速、简便、灵敏分光光度法测定葡萄糖酸锌方法,在非离子型表面活性剂聚氧乙烯失水山梨醇油酸单脂(Tween-80)及聚氧乙烯异辛基苯基醚(TritonX-100)存在下,用水溶性试剂2-(5-硝基-2-吡啶偶氮)-5-[N-正丙基-N-(3-磺酸丙基)氨基]苯酚二钠(简称Nitro-PAPS)作显色剂直接光度法测定葡萄糖酸锌。结果表明,该法显色络合物最大吸收波长为580nm,本法线性范围为0~1μg/mL,表观摩尔吸光数为1.41×105L.mol-1.cm-1,回收率为98.5%~102.8%。该法具有操作快速、简便、结果灵敏可靠等优点,应用本法直接测定补锌口服液葡萄糖酸锌含量,结果满意。  相似文献   

5.
新合成了吡啶类三氮烯显色剂1-(4-硝基苯基)-3-(3,5-二溴吡啶)三氮烯(NPDBPDT),并研究了NPDBPDT与锌的显色反应。在Na2B4O7-NaOH缓冲溶液(pH 10.0)介质中,于表面活性剂Triton X-100存在下,锌与试剂生成1∶2络合物。该络合物在450 nm处有最大正吸收峰,以540 nm为参比波长,450 nm为测量波长进行双峰双波长测定,其表观摩尔吸光系数为2.17×105L.mol-1.cm-1,锌含量在0~12μg/25mL范围内符合比耳定律。  相似文献   

6.
绿茶及其饮料中总黄酮的分析   总被引:3,自引:0,他引:3  
以绿茶及其饮料为分析对象采用三波长-光谱法测定绿茶及其饮料中黄酮的含量,有效地消除了吸收峰不对称给定量分析造成的影响,并校正了基于干扰组分(饮料中添加剂)的吸收光谱具有线性吸收产生的基线倾斜。本法的回收率为93%~106%,相对标准偏差小于0.48%。  相似文献   

7.
合成了新试剂(2,6-二氯-4-硝基苯)-3-(4-硝基苯)-三氮烯(DCNPNPT),测定了试剂的亚氨基离解常数pKa=9.2。在TritonX-100存在下,pH9.8~11.0范围内,试剂与Hg2+形成14黄色型配合物,用双波长法测得其表观摩尔吸光系数为2.27×105L·mol-1·cm-1。汞含量在0~10μg/25ml范围内符合比耳定律,用此法测定了天然水和实验室废水中微量汞含量,结果满意。  相似文献   

8.
报道了显色剂1-(4-硝基苯)-3-(3-甲基吡啶)-三氮烯的合成及其与锌的显色反应研究。在Triton X-100存在下,pH 11.0的硼砂-氢氧化钠缓冲溶液中,该试剂能与锌发生显色反应,锌与显色剂形成摩尔比为1∶4的黄色配合物,在445 nm波长处有最大正吸收峰,在535 nm波长处有最大负吸收。以445 nm为参比波长,535 nm为测量波长进行双波长测定,表观摩尔吸光系数为1.88×105L.mol-1.cm-1,锌浓度在0~12μg/25 mL范围内符合比耳定律。用拟定方法测定植物样品中微量锌,分析结果的相对标准偏差均小于2.5%,加标回收率在99.6%~100.4%之间。  相似文献   

9.
利用Fe3+-邻菲罗啉混合液为显色剂,以间接光度法测定还原型谷胱甘肽。在pH 4.0的HAc-NaAc缓冲溶液中,Fe3+-邻菲罗啉-谷胱甘肽体系显色反应的最大吸收波长为490 nm,表观摩尔吸光系数为3.93×103L/(mol.cm),吸光度与还原型谷胱甘肽的含量在0~28 mg/L内线性关系良好。该方法用于两份合成样品中还原型谷胱甘肽含量的测定,回收率分别为99.8%、103.5%。  相似文献   

10.
报道了化学发光试剂6-(2,4-二羟基苯基偶氮)-2,3-二氢-1,4-酞嗪二酮的合成。研究了试剂的物理化学性质和化学发光性能。结果表明,试剂的酸离解常数pk1=4.96,pk2=11.64。在强碱性介质中,试剂产生化学发光,最大发光波长在450nm。金属离子以Co^2 、Mn^2 、Fe^3 、Cr^3 对试剂-KOH-H2O2体系有较强的催化作用。  相似文献   

11.
《Analytical letters》2012,45(14):2883-2899
ABSTRACT|The catalytic activity of various mimetic enzymes instead of the peroxidase have been investigated by 4-aminoantipyrine (4-AAP) and 2, 3, 4-trichlorophenol (TCP) to form a dye utilizing hydrogen peroxide as hydrogen acceptor. The different Chlorophenolic derivatives, which act as a substrate in β-CD-hemin-H2O2-4-AAP catalytic reaction, have been systematically studied.|Meanwhile, the relationship of structure-effect for the β-CD-hemin as catalyst, and chlorphenols as substrate has been respectively discussed. The mechanism of catalytic reaction has been investigated. The results showed that β-CD-hemin was the best mimetic enzyme for peroxidase among those tested and TCP was a good substrate for the determination of hydrogen peroxide with β-CD-hemin. The method for the determination of hydrogen peroxide was proposed using 4-AAP-TCP system with β-CD-hemin as catalyst. A linear calibration graph was obtained over the H2O2 concentration of 4.8×10-?8-7.7×10-?5M, and the relative standard deviation at a H2O2 concentration of 2.8×10-?5M was 2.5%. The apparent molar absorptivity of the chromogenic reaction for H2O2 was 1.54× 104 L.mol-?1.cm?1. Satisfactory results were obtained in the determination of H2O2 in synthetic samples by this method.

Also, the method was coupled with the glucose oxidation reaction to determination glucose in human serum.  相似文献   

12.
A highly efficient enzyme immobilization method has been developed for electrochemical biosensors using polydopamine films with gold nanoparticles (AuNPs) embedded. This simple enzyme fabrication method can be performed in very mild conditions and stored in a long time with high bioactivity. The fabricated amperometric glucose biosensor exhibited a high and reproducible sensitivity, wide linear dynamic range and low limit of detection (LOD) (0.1 μmol·L?1). A low value of 1.5 mmol·L?1 for the apparent Michaelis‐Menten constant KappM was obtained. The high sensitivity, wide linear range, good reproducibility and stability make this biosensor a promising candidate for portable amperometric glucose biosensor.  相似文献   

13.
14.
Copper (I) oxide nanocubes (Cu2O NCs) covered with cobalt oxide nanohexagons (Co3O4 NHs) were prepared through simple chemical method. Here, ascorbic acid is used as reducing and capping agent for the synthesis of nanocubes and nanohexagons. Scanning electron microscopy (SEM), Transmission electron microscopy (TEM), Energy‐dispersive X‐ray spectroscopy (EDX) and X‐ray diffraction spectroscopy (XRD) were employed to confirm the prepared nanocomposite. Cu2O NCs?Co3O4 NHs nanocomposite is drop cast on the glassy carbon electrode (GCE) for the fabrication of glucose sensor. The fabricated Cu2O NCs?Co3O4 NHs/GCE exhibited a better electrocatalytic activity towards the determination of glucose than that of individually fabricated Cu2O NCs and Co3O4 NHs modified GCE. Our finding exhibited a wide linear range from 1 μM to 5330 μM with LOD of 0.63 towards glucose. In addition, the sensor attained appreciable stability, repeatability and reproducibility. Practicality of the sensor was demonstrated in human serum samples. The main advantages of the fabricated sensor are simple, biocompatible, cost effective, fast response and highly stable electrode surface.  相似文献   

15.
16.
应用酶反应催化性能高,反应选择性好以及离子色谱法快速,灵敏、准确的特点,率先提出酶、离子色谱法检测葡萄糖的新方法,在含葡萄糖样品溶液中加入一定量的葡萄糖氧化酶(GOD),在葡萄糖氧化酶的催化下,被测葡萄糖被氧化产生H2O2,生成的H2O2与加入的NO2^-进一步反应,生成的NO3^-用离子色谱定性和定量测定,因为被测的葡萄糖与生成的NO3^-存在定量关系,从而可以由NO3^-的浓度计算出葡萄糖的含量,测定葡萄糖的线性范围在5-100mg/L,测定了市售葡萄糖和蜂蜜中葡萄糖的含量,回收率分别为94%和94.5%。  相似文献   

17.
A non‐enzyme photoelectrochemical (PEC) glucose sensor based on α‐Fe2O3 film is investigated. The α‐Fe2O3 film was fabricated via a simple spin coating method. The proposed glucose sensor exhibits good selectivity, a fast response time of <5 s, a linear range of 0.05 to 6.0 mM, sensitivity of 17.23 μA mM?1 cm?2 and a detection limit of 0.05 μM. Meanwhile, the excellent performances of the α‐Fe2O3 sensor were obtained in reproducibility and the long‐term stability under ambient condition. The linear amperometric response of the sensor covers the glucose levels in physiological and clinical for diabetic patients. Therefore, this non‐enzyme PEC sensor based on α‐Fe2O3 film has a great potential application in the development of glucose sensors.  相似文献   

18.
The thermodynamics of the conversion of aqueous glucose to fructose has been investigated using both heat conduction microcalorimetry and high pressure liquid chromatography (HPLC). The reaction was carried out in both aqueous Tris/HCl buffer and in aqueous phosphate buffer in the pH range 7–8 using the enzyme glucose isomerase and the cofactors CoCl2 and MgSO4. The temperature range over which this reaction was investigated was 298.15–358.15 K. We have found that the enthalpy of reaction is independent of pH over the range investigated. A combined analysis of both the HPLC and microcalorimetric data leads to the following results at 298 15 K:ΔG° = 349 ± 53 J mol-1, ΔH° = 2.78 ± 0.20 kJ mol-1, and ΔC p ° = 76 ± 30 J mol-1 K-1. The stated uncertainties are based upon an analysis of both the random and systematic errors inherent in the measurements. Comparisons are made with literature data. The percent conversion of glucose to fructose has been calculated for the temperature range 300–373.15 K.  相似文献   

19.
采用交联法制备了羧基二茂铁功能化Fe3O4纳米粒子(FMC-AFNPs)复合材料,并将该复合纳米材料与多壁碳纳米管(MWNTs)、壳聚糖(CS)及葡萄糖氧化酶(GOD)混合修饰于自制的磁性玻碳基底(MGC)表面,制备了GOD/FMC-AFNPs/MWNTs/CS复合膜生物传感器电极. 实验结果表明,FMC-AFNPs复合材料有效地克服了二茂铁在电极表面的泄漏,且FMC-AFNPs/MWNTs/CS复合膜良好的生物兼容性较大地改善了固定化GOD的生物活性. MWNTs具有良好的导电性和大比表面积,在修饰膜内可作为电子传递“导线”,极大地促进电极的电子传递速率,提高电极的电催化活性和灵敏度. 该电极的葡萄糖检测的线性范围为1.0×10-5 ~ 6.0×10-3 molL-1,检测限为3.2×10-6 mmolL-1(S/N=3),表观米氏常数为5.03×10-3 mmolL-1,且有较好的稳定性和重现性.  相似文献   

20.
随机抽取1995年3月-12月间在江西省抚州地区人民医院分娩有胎儿宫内窘迫和宫内窘迫的新生儿各100例作为研究组和对照崆春脐血中血糖的变化。结果表明,血糖与胎儿宫内缺氧程度有关,宫内缺氧越严重,高血糖的比例越大,血糖与胎龄、新生儿体重上应的。  相似文献   

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