Nano Drug Delivery Research Center, Kermanshah University of Medical Sciences, Kermanshah, Iran.
Department of Chemistry, Faculty of Sciences, Azad University of Kermanshah, Kermanshah, Iran.
J Biol Inorg Chem. 2019 Oct;24(7):961-969. doi: 10.1007/s00775-019-01691-0. Epub 2019 Jul 29.
An optical bio-probe based on the immobilized tyrosinase on the surface of FeO@Au was described for the detection of dopamine, phenol and catechol. The prepared bio-probe (FeO@Au@tyrosinase) was characterized by means such as TEM, SEM, VSM, DLS and TGA. In the presence of the bio-probe, the phenol, catechol and dopamine were converted to benzoquinone, o-quinone and dopaquinone, and the fluorescence spectra appeared at 308 nm, 329 nm and 336 nm with ex = 270 nm, respectively. However, by increasing the concentration of phenolic compounds in the bio-probe, the amount of products (benzoquinone, o-quinone and dopaquinone) was increased which was the reason for the increase in fluorescence intensity. Using this mechanism, a bio-probe was designed such that the intensity of the fluorescence spectra increased proportionally with the increase of the substrate concentrations after different time periods. The 0.003 mg/mL of tyrosinase was loaded on 1.65 mg/mL of the FeO@Au. The highest performance for a bio-probe was demonstrated at room temperature and pH 6.8. By investigating the characteristics of the response of the bio-probe to different phenolic compounds, it was found that the bio-probe had a linear response in the concentration range 5.0-75.0 µM, 10.0-100.0 µM for phenol and dopamine and 50.0-500.0 M for catechol. The Michaelis-Menten constant (K) of the bio-probe was calculated as 0.6 µM. Finally, the bio-probe seems to be stable and efficient even after about 2 months. A novel and easy method for the detection of dopamine, phenol and catechol by florescence that uses oxide capability to identify the phenolic compounds was introduced.
一种基于固定在 FeO@Au 表面的酪氨酸酶的光学生物探针被描述用于检测多巴胺、苯酚和儿茶酚。通过 TEM、SEM、VSM、DLS 和 TGA 等手段对制备的生物探针（FeO@Au@tyrosinase）进行了表征。在生物探针的存在下，苯酚、儿茶酚和多巴胺被转化为苯醌、邻苯醌和多巴醌，荧光光谱分别在 308nm、329nm 和 336nm 处出现，激发波长为 270nm。然而，随着生物探针中酚类化合物浓度的增加，产物（苯醌、邻苯醌和多巴醌）的量增加，这是荧光强度增加的原因。利用这一机制，设计了一种生物探针，使得在不同时间段后，荧光光谱的强度随着底物浓度的增加而呈比例增加。在 1.65mg/mL 的 FeO@Au 上负载了 0.003mg/mL 的酪氨酸酶。该生物探针在室温下和 pH6.8 时表现出最佳性能。通过研究生物探针对不同酚类化合物响应的特性，发现生物探针在 5.0-75.0µM、10.0-100.0µM 范围内对苯酚和多巴胺以及 50.0-500.0µM 范围内对儿茶酚有线性响应。生物探针的米氏常数（K）计算为 0.6µM。最后，即使经过大约 2 个月，生物探针似乎仍然稳定且高效。介绍了一种通过氧化物能力识别酚类化合物的新型、简单的荧光检测多巴胺、苯酚和儿茶酚的方法。
