端粒酶延伸产物是具有(ggttag)n重复序列的DNA.设计1条与2个重复序列相匹配的特异性的DNA探针-(ctaacc)2使其与端粒酶延伸产物杂交,形成双链DNA.过量的DNA探针被磁性石墨烯吸附,通过磁分离去除.利用恒温指数扩增反应(IEXPAR)对端粒酶延伸产物捕捉的DNA探针进行快速的扩增.用与双链DNA特异性结合的SYBR Green I染料对扩增产物进行实时荧光检测.在优化条件下,可以检测到低至50个癌细胞中的端粒酶活性.实现了恒温扩增条件下端粒酶活性的高灵敏度检测.
Telomerase elongated product has many repeat sequences-(ggttag)n.A specific DNA probe-(ctaacc)2 which is matched with two repeat sequences is used to hybridize with telomerase elongated product.Excess DNA probes are attached to magnetic graphene and removed by magnetic separation.The DNA probes hybridized with telomerase elongated product is rapidly amplified by isothermal exponential amplification reaction(IEXPAR).SYBR Green I is utilized for real-time fluorescent detection of IEXPAR products.Under the optimal conditions,the telomerase activity in only 50 cancer cells can be easily detected.Sensitive detection of telomerase activity under isothermal condition is achieved.
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