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991.
鲁米诺-过氧化氢-四磺基锰酞菁化学发光体系测定依诺沙星 总被引:2,自引:1,他引:1
研究发现在碱性条件下,依诺沙星对Luminol-H2O2-四磺基锰钛菁(MnTSPc)体系的化学发光有较强的抑制作用,据此建立了流动注射化学发光测定依诺沙星药物的新方法.依诺沙星浓度在2.0×10-8-5.0×10-5mol/L范围内与发光信号的降低值(△I)呈良好的线性关系;检出限(3δ)为7.9×10-9mol/L;对于1.0×10-6mol/L依诺沙星进行11次测定,相对标准偏差为1.31%.应用于片剂中依诺沙星含量的测定,结果令人满意. 相似文献
992.
5-甲氧基色醇-酸性高锰酸钾-甲醛化学发光体系研究与应用 总被引:1,自引:0,他引:1
在甲醛的存在下 ,5 -甲氧基色醇 (5 - ML)与高锰酸钾在高氯酸介质中发生化学反应 ,能产生很强的化学发光。本文据此采用流动注射技术研究其发光行为 ,对影响化学发光强度的实验因素进行优化 ,建立了快速灵敏测定 5 - ML的化学发光新方法 ,测定方法的线性范围为 2 .0× 10 -8mol/ L— 4 .0× 10 -5mol/ L,检出限为 7.9× 10 -9mol/ L(S/ N=3) ,相对标准偏差为 2 .4 % (5 .7× 10 -7mol/ L5 - ML;n=10 )。该方法应用于脑脊液样品中 5 - ML含量测定 ,回收率达到 86 .0 %— 97.2 %。文中还对体系的化学发光反应机理进行探讨 相似文献
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995.
M. Rodríguez Alvarez 《Journal of luminescence》2006,118(2):193-198
The N-terminal region of human serum albumin (HSA) has an inherent affinity for Co(II) ions. On this basis a new continuous flow method for detection of HSA has been developed taking advantage of the strong quenching effect of the albumin in the ninhydrin-H2O2-Co(II) chemiluminescent system. The analytical potential of the system is compared with other conventional chemiluminescent reagents. The method gives linear responses from the detection limit (0.30 μM HSA) up to 6.8 μM. The repeatability of the method is good (RSD=7%), it is cheap and rapid to apply and does not require the use of insoluble or expensive reagents nor sophisticated equipment. 相似文献
996.
Neil W Barnett Benjamin J HindsonPhilip Jones Trevor A Smith 《Analytica chimica acta》2002,451(2):181-188
Chemiluminescence was observed during the manganese(III), (IV) and (VII) oxidations of sodium tetrahydroborate, sodium dithionite, sodium sulfite and hydrazine sulfate in acidic aqueous solution. From the corrected chemiluminescence spectra, the wavelengths of maximum emission were 689±5 and 734±5 nm when the reactions were performed in sodium hexametaphosphate and sodium dihydrogenorthophosphate/orthophosphoric acid environments, respectively. The corrected phosphorescence spectrum of manganese(II) sulfate in a solution of sodium hexametaphosphate at 77 K exhibited two peaks with maxima at 688 and 730 nm. The chemical and spectroscopic evidence presented strongly supported the postulation that the emission was an example of solution-phase chemically induced phosphorescence of manganese(II) thereby, confirming earlier predictions that the chemiluminescence from acidic potassium permanganate reactions originated from an excited manganese(II) species. 相似文献
997.
Jong-Min Park Ha-Wook Jung Young Wook Chang Hyung-Seok Kim Min-Jung Kang Jae-Chul Pyun 《Analytica chimica acta》2015
A lateral flow immunoassay (LF-immunoassay) with an enhanced sensitivity and thermostability was developed by using Pt nanoparticles with a peroxidase activity. The Pt nanoparticles were synthesized by citrate reduction method, and the peroxidase activity of Pt nanoparticles was optimized by adjusting reaction conditions. The peroxidase activity was estimated by using Michaelis–Menten kinetics model with TMB as a chromogenic substrate. The kinetics parameters of KM and Vmax were calculated and compared with horseradish peroxidase (HRP). The thermal stability of the Pt nanoparticles was compared with horseradish peroxidase (HRP) according to the storage temperature and long-term storage period. The feasibility of lateral flow immunoassay with a chemiluminescent signal band was demonstrated by the detection of human chorionic gonadotropin (hCG) as a model analyte, and the sensitivity was determined to be improved by as much as 1000-fold compared to the conventional rapid test based on colored gold-colloids. 相似文献
998.
A rapid and simple capillary electrophoresis (CE) coupled with chemiluminescence (CL) detection was proposed for analysis of nicotinamide. This method was based on the inhibitory effect of nicotinamide to CL reaction of luminol‐K3Fe(CN)6 in alkaline aqueous solution. Under the optimal conditions, nico‐tinamide can be assayed in the range of 0.01–10.0 μM with a limit of detection of 3.0 nM. The whole analysis process can be completed within 11 min. The relative standard deviations of the signal intensity and the migration time were 3.0% and 1.5% for a standard sample at 0.1 μM, respectively. The presented CE‐CL method was successfully applied to the determination of nicotinamide in yogurt, human urine and plasma samples. 相似文献
999.
《Electrophoresis》2017,38(13-14):1780-1787
An enzyme and antibody dual labeled gold nanoparticles enhancing chemiluminescence strategy was developed for highly sensitive CE immunoassay (IA) of prostate‐specific antigen (PSA). In this work, gold nanoparticles were labeled with horseradish peroxidase and antiprostate specific antigen‐antibody, and used as the marker (Ab*). After PSA (antigen, Ag) was added into the system, a noncompetitive immune reaction was happen between Ab* and Ag to form an immune complex (Ag–Ab*). Subsequently, the obtained Ag–Ab* and unreacted Ab* were separated by CE, and the chemiluminescence intensity of Ag‐Ab* was used to estimate PSA concentration. The calibration curve showed a good linearity in the range of 0.25–10 ng/mL. Based on a S/N of 3, the detection limit for PAS was estimated to be 0.092 ng/mL. Proposed CE method was applied for PSA quantification in human serum samples from healthy volunteers and patients with prostate cancer. The obtained results demonstrated that the proposed CE method may serve as an alternative tool for clinical analysis of PSA. 相似文献
1000.
以4种磺胺类药物(Sulfonamides, SAs), 即磺胺脒(Sulfaguanidine, SGD)、磺胺嘧啶(sulfadiazine, SDZ)、磺胺噻唑(sulfathiazole, STZ)和磺胺二甲嘧啶(Sulfamethazine,SMZ)为分析物,基于其在碱性介质中对Ag配合物-鲁米诺(Luminol)与Ni配合物鲁米诺两化学发光体系发光强度均具有抑制作用的性质,建立了高效液相色谱-化学发光法检测牛奶中4种磺胺类药物的方法.将化学发光体系作为高效液相色谱的新型检测器,并对两种化学发光体系的检测器性能进行了比较.4种磺胺药物经高效液相色谱分离后,分别与Ag-Luminol及Ni-Luminol化学发光体系作用.色谱条件为:反相C18分离柱(250 mm × 4.6 mm,5 μm);0.1%甲酸-甲醇为流动相(V/V);梯度洗脱;流速1 mL/min.化学发光条件:Ag、Ni-Luminol两体系中,Ag配合物浓度1.4×10.-4 mol/L(含0.12 mol/L NaOH);Ni配合物浓度1.5×10.-5 mol/L(含0.12 mol/L NaOH);Luminol浓度均为1.2×10.-7 mol/L;试剂流速均为1.0 mL/min.在最佳的分离检测条件下,Ag-Luminol体系检测4种磺胺类药物的检出限分别为0.15、0.96、1.10和1.50 μg/mL,加标回收率为81.0%~101.5%;Ni-Luminol体系检测SGD、SDZ、STZ 3种磺胺类药物的检出限分别为1.5、17.2和16.8 μg/mL,加标回收率为83.9%~110.8%.相比之下,Ag-Luminol体系作为高效液相色谱检测器更佳.应用本方法对牛奶中4种磺胺类药物残留量进行检测,结果令人满意. 相似文献