Tran Si Thanh1,2, Phan Tu Qui3, Nguyen Thi Thanh Tu4, Trần Thanh Tâm Toàn2, Tran Thi Bich Hoa2, Le Van Thanh Sơn5, Do Mai Nguyen2, Trần Ngọc Tuyền2, Đinh Quang Khiếu2
1Dak Nong Department of Education and Training, 65000, Vietnam
2University of Sciences, Hue University, 49000, Vietnam
3University of Tay Nguyen, 64000, Vietnam
4Faculty of Technology, Van Lang University, 70000, Vietnam
5University of Education and Science, The University of Da Nang, 50000, Vietnam
Tóm tắt
In the present article, the synthesis of zeolite imidazole framework-11 (ZIF-11) by ultrasonic-assisted hydrothermal process and its application as an electrode modifier for electrochemical determination of uric acid in urine are demonstrated. The obtained materials were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and nitrogen adsorption/desorption isotherms. It was found that the ZIF-11 with rhombic dodecahedron topology and high surface area (1066 m2.g-1) was synthesized in a certain temperature and found in around 25–40°C, and other crystalline phases of zinc benzimidazolate deferring from ZIF-11 phase were found in less 25°C or higher than 40°C. The ZIF-11 is stable in the pH range 6-10. The modification of glassy carbon electrode was performed with ZIF-67 using the drop-casting procedure. The present ZIF-11 modified electrode was employed to study the electrochemical behavior of uric acid (UA). UA oxidation is catalyzed by this electrode in aqueous buffer solution (pH 7) with a decrease of 70 mV in overpotential compared to glassy carbon electrode. With the differential pulse–anodic stripping voltammetry (DP-ASV) method, the oxidation current of UA versus its concentration shows good linearity in the range 20–540μM () with a detection limit of 0.48 μM (). The obtained ZIF-11 modified electrode was applied in the detection of UA content in urine samples, and satisfied results were obtained.
