基于石墨烯量子点和Fe_3O_4纳米复合探针的肾病管型的荧光成像技术的研究

目的建立一种基于石墨烯量子点(GQDs)的肾病管型荧光检测技术。方法首先,将Fe_3O_4纳米颗粒与抗人免疫球蛋白抗体(anti-IgG)结合,然后,将氨基化修饰的GQDs连接到Fe_3O_4/anti-IgG表面,构建荧光探针。为了避免交联试剂N-羟基琥珀酰亚胺(NHS)对GQDs的荧光猝灭效应,只加入交联试剂1-(3-二甲基氨丙基)-3-乙基碳二亚胺盐酸盐(EDC)。再用牛血清清蛋白(BSA)封闭纳米颗粒上的剩余活性基团。最后,将Fe3O4/GQDs复合材料作为荧光探针,标记样品中的管型,再用荧光成像进行检测,对该方法进行初步性能评价。结果 Anti-IgG、GQDs与Fe_3O_4纳米颗粒表面连接后通过透射电子显微镜成像显示连接成功。GQDs的荧光强度没有在Fe_3O_4/anti-IgG连接后明显下降。这种荧光检测方法具有高灵敏度(最低检出限为2mL~(-1))、高特异性及线性范围宽(2~2 000mL~(-1))的特点,可对肾病患者尿中的管型(红细胞管型、白细胞管型、颗粒管型)进行准确定量分析。结论这种标记管型荧光成像分析可作为肾病诊断的新方法。

Fluorescence imaging of nephropathy casts based on amine-modified graphene quantum dots and nano Fe3 O4 composite probes

Objective To establish a method for fluorescence imaging of nephropathy casts based on amine‐modified graphene quantum dots and nano Fe3 O4 composite probes .Methods First ,Fe3 O4 nanoparticles were conjugated with anti human IgG anti‐body(anti‐IgG) .Then ,connect the amine‐modified graphene quantum dots (GQDs) to the surface of Fe3 O4/anti‐IgG nanocompos‐ites .In order to avoid the fluorescence quenching effect of crosslinking reagent NHS ,only cross‐linking reagent EDC was added .Af‐ter that ,bovine serum albumin(BSA) was used to block the remaining active groups on nanoparticles .Finally ,the Fe3O4/GQDs composites as fluorescent probes were used to detect the casts in clinical samples and preliminary performance evaluation of this method was done .Results The electron microscope showed that the anti‐IgG ,GQDs with Fe3 O4 nanoparticles were connected suc‐cessfully .The fluorescence intensity of GQDs weren′t decrease after Fe3 O4/anti‐IgG connection .The fluorescence detection method was with high sensitivity(the limits of detection was 2 mL -1 ) ,high specificity and wide linear range (2-2 000 mL -1 ) ,and can be used for accurate and quantitative analysis of various types of casts ,including red blood cell ,white blood cell and granular casts . Conclusion This fluorescent imaging analysis can be used as a new method for diagnosis of renal failure .