Abstract
•Gold nanoparticles was functionalized by 4-amino-3-hydrazino-5-mercapto-1, 2, 4-triazole (AHMT) and then applied to detect kanamycin based on hydrogen-bonding recognition.•A low detection limit of 0.004μM was obtained for kanamycin detection.•The sensor showed an application potential for detecting kanamycin in various samples.•The sensor demonstrated another promising application of gold nanoparticles in simple and sensitive detection of organic molecules.
The authors here described a visual detection strategy employing 4-amino-3-hydrazino-5-mercapto-1, 2, 4-triazole (AHMT) functionalized gold nanoparticles (AuNPs) to detect kanamycin (KA) in various samples. The AHMT with mercapto group was self-assembled onto the surface of AuNPs and the AHMT functionalized AuNPs (AHMT-AuNPs) aggregated when KA existed owing to the hydrogen-bonding interaction between KA and AHMT. As a result, the color of the AHMT-AuNPs solution changed from wine red-to-deep purple with the increasing concentration of KA. Taking advantage of the hydrogen-bonding interaction, KA could be quantitatively detected by the proposed sensor in the range of 0.005–0.1μM and 0.1–20μM, with the detection limit as low as 0.004μM which is much lower than the maximum contamination level for KA in milk defined by the European Union. Furthermore, the proposed sensor was not affected by the interference chemicals including common amine acid, antibiotics, and metal ions. The sensor was also used to detect KA from various real samples, and the results were excellent in accord with the values measured by the high performance liquid chromatography (HPLC). This sensor exhibited a promising potential for simple and real-time detection of KA in various real samples.