NEW METHYLENE BLUE (NMB) ENCAPSULATED IN MESOPOROUS ALMCM-41 MATERIAL AND ITS APPLICATION FOR AMPEROMETRIC DETERMINATION OF ASCORBIC ACID IN REAL SAMPLES
NEW METHYLENE BLUE (NMB) ENCAPSULATED IN MESOPOROUS ALMCM-41 MATERIAL AND ITS APPLICATION FOR AMPEROMETRIC DETERMINATION OF ASCORBIC ACID IN REAL SAMPLES
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介孔ALCM-41材料封装的新型亚甲基蓝(NMB)及其在安培测定实际样品中抗坏血酸的应用
DOI：
10.1002/elan.200703898
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发表时间：
2007
期刊：
影响因子：
3
通讯作者：
A. Pourahmad
中科院分区：
文献类型：
--
作者：
S. Sohrabnezhad;A. Pourahmad
新亚甲基蓝（NMB）染料加入到AlMCM-41无表面活性剂和杂化表面活性剂-AlMCM-41中间相。紫外-可见证据表明，新的亚甲基蓝染料在两种情况下的沸石质子化。新亚甲基蓝在沸石中具有电活性，用循环伏安法研究了其电化学活性，并与NMB在水溶液中的电化学活性进行了比较。在CV测量期间，新的亚甲基蓝分子不会释放到溶液中，并且可以被h30 +离子访问。表面活性剂的存在影响了质子离子扩散氧化还原过程的动力学。中点电位（Em）值表明，AlMCM-41中加入的新亚甲基蓝染料相对于溶液中的新亚甲基蓝容易还原。结果表明，新亚甲基蓝溶液与表面活性剂极性头和残留的Br离子相互作用，形成了一对高电位峰。以亚甲基蓝- almcm -41为电极制备了无表面活性剂的抗坏血酸氧化电极。循环伏安法观察到的阳极峰电流与抗坏血酸浓度呈线性关系。校正图在抗坏血酸浓度范围1.0×10−5 ~ 5.0×10−4 M内呈线性关系，检测限为1.0×10−5 M，可用于各种实际样品中微量抗坏血酸的测定。
New methylene blue (NMB) dye incorporated into AlMCM-41 surfactant-free and hybrid surfactant-AlMCM-41 mesophase. UV-vis evidence shows that new methylene blue dye protonated in both cases of zeolites. New methylene blue is electroactive in zeolites and their electrochemical activity has been studied by cyclic voltammetry and compared to that of NMB in aqueous solutions. New methylene blue molecules are not released to the solution during CV measurements and are accessible to H3O+ ions. The presence of surfactant affects the kinetics of the redox process through proton ions diffusion. The midpoint potentials (Em) values show that new methylene blue dye incorporated into AlMCM-41 can be reduced easily with respect to solution new methylene blue. New methylene blue interacting with surfactant polar heads and residual Br− ions as a results, it shows a couple of peaks in high potential with respect to new methylene blue solution. The electrode made with methylene blue-AlMCM-41 without surfactant was used for the mediated oxidation of ascorbic acid. The anodic peak current observed in cyclic voltammetry was linearly dependent on the ascorbic acid concentration. The calibration plot was linear over the ascorbic acid concentration range 1.0×10−5 to 5.0×10−4 M. The detection limit of the method is 1.0×10−5 M, low enough for trace ascorbic acid determination in various real samples.