Phosphate-modified TiO2 nanoparticles for selective detection of dopamine, levodopa, adrenaline, and catechol based on fluorescence quenching.
Phosphate-modified TiO2 nanoparticles for selective detection of dopamine, levodopa, adrenaline, and catechol based on fluorescence quenching.
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DOI：
10.1021/la700555y
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发表时间：
2007-06
期刊：
影响因子：
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通讯作者：
H. Wu;Tian‐Lu Cheng;W. Tseng
中科院分区：
文献类型：
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作者：
H. Wu;Tian‐Lu Cheng;W. Tseng
第一次，包含6-nm磷酸盐改性的二氧化钛（P-TiO 2）纳米颗粒（NP）和荧光素的水溶液已被用于感测多巴胺（DA）、左旋多巴（L-DOPA）、肾上腺素和儿茶酚。通过螯合的表面Ti（IV）离子与englutamine基团的装置获得的配合物在428 nm处表现出强吸收，因此，它们可以被设计为有效的荧光素猝灭剂。如果溶液包含DA、L-DOPA、肾上腺素和儿茶酚，但不包含去甲肾上腺素、抗坏血酸和水杨酸，则含有1.4mM P-TiO 2 NP的荧光素溶液在pH 8.0下的荧光降低。我们认为，P-TiO 2纳米粒子具有许多优点，裸TiO 2纳米粒子，如易于制备，高选择性，和高稳定性。通过测量荧光猝灭，在信噪比为3时，DA、L-DOPA、肾上腺素和儿茶酚的检测限分别计算为33.5、81.8、20.3和92.1 nM。相比之下，紫外-可见吸收揭示了这些化合物的相对较差的灵敏度。我们已经验证了我们的方法的适用性，通过分析尿样中的DA。高效液相色谱结合电化学电池已被用来进一步证实我们的结果。我们认为，这种方法在诊断方面具有很大的潜力。
For the first time, an aqueous solution, comprising 6-nm phosphate-modified titanium dioxide (P-TiO2) nanoparticles (NPs) and fluorescein, has been used for sensing dopamine (DA), levodopa (L-DOPA), adrenaline, and catechol. The complexes obtained by means of chelation of surface Ti(IV) ions with an enediol group exhibit strong absorption at 428 nm; thus, they can be designed as efficient quenchers for fluorescein. The fluorescence of a fluorescein solution containing 1.4 mM P-TiO2 NPs at pH 8.0 decreases if the solution comprises DA, L-DOPA, adrenaline, and catechol, but not noradrenaline, ascorbic acid, and salicylic acid. We consider that P-TiO2 NPs have a number of advantages over bare TiO2 NPs, such as ease of preparation, high selectivity, and high stability. By measuring fluorescence quenching, the limits of detection at a signal-to-noise ratio of 3 are calculated as 33.5, 81.8, 20.3, and 92.1 nM for DA, L-DOPA, adrenaline, and catechol, respectively. In contrast, UV-vis absorption reveals the relatively poor sensitivity of these compounds. We have validated the applicability of our method by means of analyses of DA in urine samples. High-performance liquid chromatography in combination with an electrochemical cell has been used to further confirm our results. We believe that this approach has great potential for diagnostic purposes.