The identification of tumor-related microRNAs(miRNAs)exhibits excellent promise for the early diagnosis of cancer and other bioanalytical applications.Therefore,we developed a sensitive and efficient biosensor using p...The identification of tumor-related microRNAs(miRNAs)exhibits excellent promise for the early diagnosis of cancer and other bioanalytical applications.Therefore,we developed a sensitive and efficient biosensor using polyadenine(polyA)-mediated fluorescent spherical nucleic acid(FSNA)for miRNA analysis based on strand displacement reactions on gold nanoparticle(AuNP)surfaces and electrokinetic signal amplification(ESA)on a microfluidic chip.In this FSNA,polyA-DNA biosensor was anchored on AuNP surfaces via intrinsic affinity between adenine and Au.The upright conformational polyA-DNA recognition block hybridized with 6-carboxyfluorescein-labeled reporter-DNA,resulting in fluorescence quenching of FSNA probes induced by AuNP-based resonance energy transfer.Reporter DNA was replaced in the presence of target miRNA,leading to the recovery of reporter-DNA fluorescence.Subsequently,reporter-DNAs were accumulated and detected in the front of with Nafion membrane in the microchannel by ESA.Our method showed high selectivity and sensitivity with a limit of detection of 1.3 pM.This method could also be used to detect miRNA-21 in human serum and urine samples,with recoveries of 104.0%-113.3% and 104.9%-108.0%,respectively.Furthermore,we constructed a chip with three parallel channels for the simultaneous detection of multiple tumor-related miRNAs(miRNA-21,miRNA-141,and miRNA-375),which increased the detection efficiency.Our universal method can be applied to other DNA/RNA analyses by altering recognition sequences.展开更多
基金supported financially by the National Natural Science Foundation of China(Grant No.:81973282)Guangdong Basic and Applied Basic Research Foundation(Grant Nos.:2018A030313843 and 2021A1515011493)+3 种基金National College Students Innovation and Entrepreneurship Training Program(Grant No.:202012121024)Science and Technology Innovation Strategic Special Project of Guangdong Province("Climbing Program"Special ProjectGrantNo.:pdjh2022b0106)Guangdong College Students Innovation and Entrepreneurship Training Program(Grant No.:S202112121154).
文摘The identification of tumor-related microRNAs(miRNAs)exhibits excellent promise for the early diagnosis of cancer and other bioanalytical applications.Therefore,we developed a sensitive and efficient biosensor using polyadenine(polyA)-mediated fluorescent spherical nucleic acid(FSNA)for miRNA analysis based on strand displacement reactions on gold nanoparticle(AuNP)surfaces and electrokinetic signal amplification(ESA)on a microfluidic chip.In this FSNA,polyA-DNA biosensor was anchored on AuNP surfaces via intrinsic affinity between adenine and Au.The upright conformational polyA-DNA recognition block hybridized with 6-carboxyfluorescein-labeled reporter-DNA,resulting in fluorescence quenching of FSNA probes induced by AuNP-based resonance energy transfer.Reporter DNA was replaced in the presence of target miRNA,leading to the recovery of reporter-DNA fluorescence.Subsequently,reporter-DNAs were accumulated and detected in the front of with Nafion membrane in the microchannel by ESA.Our method showed high selectivity and sensitivity with a limit of detection of 1.3 pM.This method could also be used to detect miRNA-21 in human serum and urine samples,with recoveries of 104.0%-113.3% and 104.9%-108.0%,respectively.Furthermore,we constructed a chip with three parallel channels for the simultaneous detection of multiple tumor-related miRNAs(miRNA-21,miRNA-141,and miRNA-375),which increased the detection efficiency.Our universal method can be applied to other DNA/RNA analyses by altering recognition sequences.
