碳点-核酸/氧化石墨烯荧光探针用于miRNA-21的细胞成像

CD-DNA/GO Fluorescent Nanoprobe for Detection of miRNA-21 in situ Live Cell

通过生物偶联方式,将无毒的碳点(Carbon Dots,CD)表面功能化上核酸,以核酸功能化的碳点(CD-DNA)为荧光团,氧化石墨烯(GO)为猝灭剂,二者组装成CD-DNA/GO纳米荧光探针,CD与GO之间产生长程共振能量转移(long-range resonance energy transfer,LrRET),CD荧光猝灭。当miRNA-21存在时,DNA与其杂交,CD从GO表面分离,二者之间的荧光共振能量转移被打断,碳点荧光恢复,通过荧光"开"方式检测miRNA-21,检测限为0.2nmol/L,线性范围为1~500nmol/L。该探针成功应用于血癌K562细胞中miRNA-21的原位成像,为血癌的原位诊断和治疗提供了研究依据。

By using carbon dots（CD）to label DNA as fluorophore by biological coupling method,combining with graphene oxide（GO）as quencher,CD-DNA/GO fluorescent nanoprobe was constructed,and developed for miRNA-21 detection.In CD-DNA/GO,the fluorescence of CD was quenched by GO through long-range resonance energy transfer（LrRET）.In present of miRNA-21,the DNA bind with miRNA-21 to form duplex,releasing CD-DNA from GO and interrupting the LrRET,and the fluorescence of CD was recovery to achieve miRNA-21 detection by fluorescence＂turn on＂mode.The obtained the linear range for miRNA-21 was from 1 nmol/L to 500 nmol/L;the detection of limit was estimated to be 0.2 nmol/L by the miRNA-21 fluorescent nanoprobe.The nanoprobe was achieved for detection of miRNA-21 in situlive cell imaging,which provide the basic research for in situ diagnosis and treatment of leukemia.