背景:动物源性食品中的卡那霉素(KAN)残留物不断进入人体,这将对人类健康构成严重威胁,如听力损失,肾毒性和其他并发症。因此,通过可靠的技术灵敏检测KAN残留在食品质量和安全方面迫在眉睫。与传统方法受到成本和复杂性的限制相比,光电化学(PEC)生物传感器受益于一些优点,如快速响应,优异的灵敏度和良好的稳定性。在这项研究中,探讨了构建高效PEC平台实现KAN残留检测的方法。
结果:这里,开发了一种由花状BiOI微球和氮化石墨碳(g-C3N4)纳米片组成的新型p-n异质结,以建立用于0V下KAN检测的PECaptasensor。制备的g-C3N4/BiOI异质结构不仅由于较大的比表面积而显着增强了PEC活性,而且由于强大的内部电场而大大提高了电荷分离效率。同时,使用g-C3N4/BiOI作为结合胺官能化适体捕获KAN的高效光活性材料,光电流信号显示“关闭”模式,以实现对KAN的灵敏检测。拟议的PEC适应量对KAN在5×10-9至3×10-7molL-1范围内呈线性响应,低检测限为1.31×10-9molL-1,并且令人满意的回收率(97.44-107.38%)在实际食品样品分析中获得。
结论:这项工作提出了一种新型的基于p-n异质结的PECaptasensor,具有很强的选择性和稳定性,它允许在包括牛奶在内的动物源性食品中检测到KAN,蜂蜜和猪肉此外,检测范围满足国家标准规定的KANMRL,展示了食品分析的潜在应用。该研究为开发高效实用的抗生素残留检测生物传感器提供了新的见解。
BACKGROUND: Kanamycin (KAN) residues in animal-derived foods continuously enter the human body, which will pose serious threats to human health such as hearing loss, nephrotoxicity and other complications. Therefore, to sensitively detect KAN residues by a reliable technology is extremely urgent in food quality and safety. Compared with traditional methods being limited by cost and complexity, photoelectrochemical (PEC) biosensors benefit from some merits such as rapid response, excellent sensitivity and good stability. In this study, the construction of a highly efficient PEC platform to realize KAN residues detection is discussed.
RESULTS: Herein, a novel p-n heterojunction consisting of flower-like BiOI microspheres and graphite carbon nitride (g-C3N4) nanoflakes was developed to establish a PEC aptasensor for KAN detection at 0 V. The prepared g-C3N4/BiOI heterostructure showed not only significantly enhanced PEC activity due to the larger specific surface area but also greatly increased charge separation efficiency owing to the strong internal electric field. Meanwhile, using g-C3N4/BiOI as a highly efficient photoactive material for binding amine-functionalized aptamers to capture KAN, the photocurrent signals showed a \'turn off\' mode to achieve the sensitive detection of KAN. The proposed PEC aptasensor exhibited linear response for KAN from 5 × 10-9 to 3 × 10-7 mol L-1 with a low detection limit of 1.31 × 10-9 mol L-1, and satisfactory recoveries (97.44-107.38 %) were obtained in real food samples analysis.
CONCLUSIONS: This work presented a novel p-n heterojunction-based PEC aptasensor with strong selectivity and stability, rendering it allowed to detect KAN in animal-derived foods including milk, honey and pork. Additionally, the detection range satisfied the MRLs for KAN specified by the national standards, demonstrating the potential application for food analysis. The study provides a new insight into the development of efficient and practical biosensors for antibiotic residues detection.