摘要
旨在制备基于碳量子点(carbon quantum dots, CDs)的免疫荧光探针,初步建立鼠伤寒沙门菌的快速检测方法,以柠檬酸和尿素作为碳源,利用微波法对碳量子点制备的微波时间、透析袋规格等条件进行了优化,再使用化学偶联法将碳量子点与鼠伤寒沙门菌抗体结合制备免疫荧光探针C-IgG,使之借助抗原抗体特异性结合和荧光实现对鼠伤寒沙门菌的检测,最后通过荧光信号对探针的特异性及灵敏度进行检测。结果显示:微波时间为5 min,透析袋规格为MWCO=1 000时能获得粒径3~11 nm的理想碳量子点;该碳量子点激发波长为408 nm,紫外吸收峰位于337 nm,傅里叶变换红外光谱显示其含有羟基、羧基、氨基等常见官能团;制备的免疫荧光探针C-IgG能在短时间内特异性结合沙门菌并在荧光显微镜不同光束下呈多色荧光点,灵敏度为10;CFU/mL。结果表明:改变微波时间和透析袋规格可制备出粒径3~11 nm,表面多功能基团,用于鼠伤寒沙门菌检测的碳量子点,为进一步探索基于碳量子点的免疫荧光探针在鼠伤寒沙门菌检测中的应用提供了参考。
This study was to prepare an immunofluorescence probe based on carbon quantum dots(CDs) and to establish a method for rapid detection of Salmonella typhimurium. The preparation time and dialysis bag specifications of CDs were optimized using the microwave method with citric acid and urea as the carbon sources. The immunofluorescence probe C-IgG was prepared by combining CDs with Salmonella typhimurium antibodies using the chemical coupling method, so as to detect Salmonella typhimurium by specific binding of the antigen antibody and fluorescence. Finally, the specificity and sensitivity of the probe were detected by the fluorescence signal. The results showed that the ideal CDs with particle sizes of 3-11 nm were obtained using the microwave time of 5 min and the dialysis bag(MWCO=1 000). The excitation wavelength of the CDs was 408 nm, and the ultraviolet absorption peak was located at 337 nm. Fourier transform infrared spectrum showed that the prepared carbon quantum dots contained hydroxyl, carboxyl, amino and other common functional groups. The prepared immunofluorescence probe C-IgG specifically bound with Salmonella typhimurium in a short time and showed polychromatic fluorescence spots under different light beams of the fluorescence microscope, with a sensitivity of 10;CFU/mL. The present result indicated that CDs with a diameter of 3-11 nm and a surface functional group could be prepared by changing the microwave time and the size of the dialysis bag, which provided a reference for further exploration of application of immunofluorescence probes based on CDs in detection of Salmonella typhimurium.
作者
孙路
程如楠
宋想胜
李磊
王真
SUN Lu;CHENG Runan;SONG Xiangsheng;LI Lei;WANG Zhen(College of Animal Science and Technology,Beijing University of Agriculture,Beijing 102206,China)
出处
《畜牧与兽医》
北大核心
2022年第2期102-106,共5页
Animal Husbandry & Veterinary Medicine
基金
北京农学院青年科学基金(QNKJ202107)
北京农学院学位与研究生教育改革与发展项目(2020YJS042)
北京市优秀人才培养项目(2017000026833ZK18)
2019年北京市属高校高水平教师队伍建设支持计划——青年拔尖人才培育计划项目(CIT&201904-052)。
关键词
碳量子点
免疫荧光探针
鼠伤寒沙门菌
检测
carbon quantum dots
immunofluorescence probe
Salmonella typhimurium
detection
