碳量子点应用于鼠伤寒沙门菌检测的初步研究

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...

Preliminary study on the application of carbon quantum dots in the detection of Salmonella typhimurium

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.