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儿茶酚胺是一类非常重要的神经递质,在人体的心血管系统、神经系统、内分泌腺、肾脏、平滑肌等组织系统的生理活动中起着广泛的调节作用。肾上腺素为儿茶酚胺的一种,建立灵敏、高效的肾上腺素检测技术具有重要的临床意义。本文将银(Ⅲ)配合物与鲁米诺组成新的流动注射化学发光体系,利用碱性介质中肾上腺素对三价银配合物-鲁米诺化学发光体系有明显的增强效应来测定肾上腺素的含量,并据此建立了高效测定肾上腺素的流动注射化学发光新方法。在优化的条件下,该方法测定肾上腺素的线型范围为1.0×10-9~1.0×10-7 mol L-1,检出限为8.0×10-10 mol L-1,对1.5×10-8 mol L-1肾上腺素11次平行测定,其相对标偏差为2.9%。利用建立的分析方法测定了药物肾上腺素,并对三价银-鲁米诺化学发光新体系测定肾上腺素的反应机理进行了讨论。 相似文献
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痕量铁的催化分光光度法研究 总被引:4,自引:0,他引:4
研究了在S2SO4介质中,以1,10-二氮菲为活化剂,铁(Ⅲ)催化过氧化氢氧化甲基橙的褪色反应的动力学条件。建立了测定痕量铁(Ⅲ)的动力学分析法。方法的灵敏度1.78×10-8g·L-1,线性范围0~1.2×10-5g·L-1。用于测定饮用水和湖水中的痕量钱,相对标准差在5%以内,平均回收率97%~106%。 相似文献
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发现钙黄绿素可以吸收铁氰化钾氧化酮替芬反应的化学能而产生化学发光, 以钙黄绿素为化学发光试剂, 构建了铁氰化钾-酮替芬-钙黄绿素化学发光体系, 利用此体系建立了测定酮替芬的化学发光分析新方法, 方法的线性范围为2.0×10-8~6.0×10-6 g•mL-1, 检出限为8×10-9 g•mL-1, 对浓度为5.0×10-7 g•mL-1酮替芬溶液进行11次平行测定的相对标准偏差(RSD)为2.1%. 此法已用于药品中酮替芬含量的测定, 结果与药典测定结果一致. 对化学发光反应的机理也进行了初步的探讨. 相似文献
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《Analytical letters》2012,45(17):3290-3308
Abstract The present work describes the development of a simple and efficient method for electrochemical analysis determination of SBS using polymer film coated modified electrode. A glassy carbon electrode (GCE) is successfully modified with electropolymerized film of aminosulfonic acid (ASA) in pH 6.8 phosphate buffer solution (PBS). Cyclic voltammetry (CV) were used to study the electrochemical properties of the polymer film and the appropriate condition for electropolymerization process. The voltammetric behavior of SBS at the PASA GC CMEs has been investigated, the results suggest that the PASA GC CMEs have good effect of electrocatalytic oxidation action to SBS, also propose the mechanism toward SBS. The flow‐injection irreversible biamperometry analysis method was studied under the applied potential difference of 0 V to determinate SBS. In 0.1 mol l?1 (pH 6.80) phosphate buffer solution, a sensitive and irreversible oxidation peak was obtained at the PASA GC CMEs. Under the optimum conditions, SBS can be determined from the range 2.0×10?6 to 1.0×10?3 mol · 1?1 with the sampling frequency of 100 samples per hour. The detection limit for SBS is 6.5×10?7 mol l?1 and the RSD for 20 replicate determinations of 4.0×10?5 mol l?1 SBS is 1.85%. The method is simple, with high selective rapid and sensitive. The method is applied to the determination of SBS in the drug with satisfactory results. Moreover, the physiologically common interferents (i.e., sucrose, lactose, citric acid, and citrate) negligibly affected the response of SBS. The PASA GC CMEs film‐coated electrode exhibited a stable and sensitive response to salbutamol sulfat in the presence of electrocatalysis oxidation. 相似文献
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将金纳米粒子(AuNPs)电沉积在N,P/石墨烯(N,P/Graphene)修饰的玻碳电极表面,研究了维生素B_6(VB_6)在该修饰电极上的电化学行为。实验结果表明:VB_6在该修饰电极上出现一个良好的氧化峰,在最佳实验条件下,其氧化峰电流与VB_6的浓度在2.0×10~(-5)~4.0×10~(-4) mol/L范围内呈线性关系,相关系数R=0.998,检出限为9.2×10~(-6) mol/L。一些常见的物质如K~+、Na~+、Zn~(2+)、葡萄糖(Glu)不干扰VB_6的检测。此方法已用于片剂中VB_6含量的检测,获得较好结果。 相似文献
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《Analytical letters》2012,45(13):2631-2644
ABSTRACT An unmediated hydrogen peroxide sensor is designed in this paper by employing a hemoglobin-SDS film modified electrode. Hemoglobin exhibits direct (unmediated) electrochemistry at the modified electrode. The protein also shows elegant catalytic activity towards the electrochemical reduction of hydrogen peroxide. Consequently, a prototype hydrogen peroxide sensor is prepared. Under optimum conditions, this sensor provides a linear response over the hydrogen peroxide concentrations in the range of 1×10-5~1×10-4 mol/L. The detection limit was 2×10-6 mol/L The relative standard deviation was 4.2% for 6 successive determinations of the hydrogen peroxide at 1×10-5 mol/L. This configuration is shown to be sensitive, stable and easily fabricated. It might be useful in the biological and industrial fields. 相似文献
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基于β-环糊精(β-CD)主客体竞争模式,构建了开关型凝血酶适配体电化学传感器.将末端修饰了二茂铁(Fc)的核酸适配体通过与β-CD的主客体识别固定在金电极表面,当凝血酶存在时,适配体由原来的直立线状构型变为"G-四链体",远离电极表面,适配体探针的氧化还原电流强度减小,即"Signal-off".利用此效应对凝血酶进行了灵敏检测,结果表明,在5.0×10-13~5.0×10-9 mol/L浓度范围内,凝血酶的浓度与电化学响应信号呈良好的线性关系,检出限为2.0×10-13 mol/L(3σ).与其它蛋白分子相比,本方法对凝血酶蛋白的检测具有高特异性.本传感器构建简单,再生性好,为生物血清样本中凝血酶的实时高效检测提供了方法. 相似文献
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将功能化离子液体修饰石墨烯(IL-GR)分散在聚乙烯醇(PVA)中,制得IL-GR-PVA分散液,与乙酰胆碱酯酶(ACh E)溶液混匀后滴涂在电极表面,利用PVA良好的成膜特性,制得新型有机磷检测酶电极ACh E/IL-GR-PVA/GCE,并用于有机磷农药的检测。采用透射电镜(TEM)表征了IL-GR的形貌,采用循环伏安法(CV)和差示脉冲伏安法(DPV)研究了酶电极的电化学性质。结果表明,IL-GR-PVA复合膜具有良好的导电性和生物相容性,能很好地保持ACh E的生物活性,并显著促进了其电化学过程。在优化实验条件下,抑制率(I%)与甲拌磷浓度的负对数在1.0×10-14~1.0×10-9mol/L和1.0×10-9~1.0×10-6mol/L范围内呈良好的线性关系,检出限(S/N=3)为8.0×10-15mol/L。该传感器制备简单,稳定性好,灵敏度高,为有机磷农药的测定提供了新方法。 相似文献
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Electrochemical Behavior and Determination of Phenylephrine at Silicate Nanotubes Modified Electrode
A novel Silicate nanotubes (SNTs) modified glass carbon (GC) electrode was prepared and used to study the electrochemcial behavior of phenylephrine (PHE) and determine it. The enhanced electrochemical response of PHE at SNTs modified electrode was observed as compared with bare GC electrode. This proposed method displayed a broad linear range and a lower detection limit for PHE. The linear range was from 8 × 10?8 M to 2 × 10?5 M with the detection limit of 1 × 10?8 M. The electrode could be easily regenerated and exhibited high stability and good selectivity. This method was successfully applied to the determination of PHE in drug samples with satisfactory result. The strategy presented here opens a new way for the development of nanoelectronic devices or electrochemical sensors based on SNTs. 相似文献
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采用循环伏安法制备了聚L-苯丙氨酸薄膜修饰玻碳电极,研究了尿酸在该修饰电极上的电化学行为,建立了循环伏安法测定尿酸的新方法。研究发现:在pH 5.6的磷酸盐缓冲溶液中,尿酸在聚L-苯丙氨酸修饰电极上于0.43V处产生一灵敏的氧化峰,应用循环伏安法测定其氧化峰电流与尿酸的浓度在2.0×10-6~3.0×10-4 mol/L呈良好的线性关系,检出限为1×10-6 mol/L。对1.0×10-5 mol/L尿酸平行测定5次,相对标准偏差为3.0%。该生物分子电极制作简单,重现性好,可用于尿液中尿酸的测定,结果令人满意 相似文献
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基于羧基化多壁碳纳米管修饰的玻碳电极(CMWCNTs/GCE),构建了一种灵敏检测氨基脲(SEM)的电化学传感器.采用傅里叶变换红外光谱、透射电子显微镜、电化学阻抗谱对修饰材料进行表征.结果表明,羧基化的多壁碳纳米管出现羧基碳氧双键的红外特征峰,管径明显减小,长度变短,电化学阻抗值显著减小.在1 mol/L HAc-NaAc缓冲液中,利用循环伏安法和时间-电流曲线研究了SEM在CMWCNTs修饰电极上的电化学行为.SEM在修饰电极上呈现不可逆的氧化峰.与裸电极相比,氧化峰电流明显增大.在最佳实验条件(pH 7.0,扫描速度为0.1 V/s)下,测得SEM在5.00×10-6~1.09×10-3mol/L浓度范围内与氧化峰电流呈线性关系,线性方程为IP(μA)=-0.472+0.0599C(μmol/L),相关系数r=0.997,检出限为1.88×10-7 mol/L(S/N=3).在实际猪肝样品检测中加标回收率为92.8%~98.0%. 相似文献
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以水合肼为还原剂,采用均相还原法制备还原氧化石墨烯-多壁碳纳米管复合材料(rGO-MWCNTs),通过滴涂法将其修饰到玻碳电极(GCE)表面.以此复合材料为载体,采用电化学方法制备了金纳米粒子-还原氧化石墨烯-多壁碳纳米管复合膜修饰电极(AuNPs-rGO-MWCNTs/GCE).通过扫描电镜(SEM)、EDS能谱技术和电化学方法对此电极进行了表征.研究了双酚A在修饰电极上的电化学行为.结果表明,此电极对双酚A的电极过程具有良好的电化学活性,在0.10 mol/L PBS溶液(pH 7.0)中,微分脉冲伏安法测定双酚A的线性范围为5.0 × 10-9~1.0 × 10-7 mol/L和1.0 × 10-7~2.0 × 10-5 mol/L,检出限为1.0 ×10-9 mol/L(S/N=3). 将此电极用于模拟水样和超市购物小票样品中双酚A含量的测定,加标回收率分别为97%~110%和98%~104%. 相似文献