基于抗体标记的新型碳点在呕吐毒素检测中的研究

Study on a novel carbon dots based on antibody labeling in detection of deoxynivalenol

目的免疫荧光技术是标记免疫技术中发展最早、灵敏度高、特异性强的检测技术,本研究期望利用该技术制备1种低毒、经济、高效的碳点作为免疫荧光的标记物,并将其标记于呕吐毒素抗体上,利用这种免疫探针去检测识别样品中的呕吐毒素(deoxynivalenol,DON)。方法利用聚乙烯亚胺(polyethyleneimine,PEI)作为表面修饰剂,以柠檬酸为碳源通过微波辅助法制备了1种可以标记于抗体上的碳点,并使用氨基/羧基偶联的方法将这种碳点与DON的抗体相结合,制成免疫荧光探针并镜下观察探针与DON结合的情况。结果这种碳点在激发光为334 nm时能够发出445 nm的强烈蓝光,经过红外表征确定该碳点表面含有羧基,以及PEI所修饰的氨基,因此能够与表面含氨基的抗体结合,并能够发出荧光信号,作为免疫荧光探针去检测相应抗原,在荧光显微镜下观察到荧光信号。结论将制备的荧光碳点通过氨基/羧基偶联的方法与抗体结合制备了呕吐毒素的免疫荧光探针,并成功将这种免疫探针用于检测DON。

Objective The immunofluorescence technology is the earliest developed detection technology with high sensitivity and strong specificity.It is expected to use this technology to prepare a low toxicity,economic and efficient carbon dots as a marker of immunofluorescence,label it on deoxynivalenol(DON)antibodies,so as to identify DON in samples by using this immunoprobe.Methods The polyvinylimide was used as surface modifier and citric acid as carbon source to prepare a carbon dots which could be labeled on antibody by using the microwave-assisted method.The amino/carboxyl coupling method was used to bind this carbon dot with DON antibodies to produce an immunofluorescence probe,and the binding of the probe with DON was observed under the microscope.Results When the excitation light was 334 nm,this carbon dots could emit a strong blue light of 445 nm.The infrared characterization showed that the surface of this carbon spot contains carboxyl group and amino groups modified by PEI,so it could be combined with the surface of the antibody containing amino group and could emit fluorescent signals.As an immunofluorescence probe to detect the corresponding antigen,fluorescence signals were observed under a fluorescence microscope.Conclusion The immunofluorescence probe of DON is prepared by combining the prepared fluorescent carbon dots with antibodies by amino/carboxyl coupling method,and this immune probe is successfully used for detecting DON.