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Graphene oxide assisted light-up aptamer selection against Thioflavin T for label-free detection of microRNA.

ABSTRACT: We selected an aptamer against a fluorogenic dye called Thioflavin T (ThT). Aptamers are single-stranded DNA that can bind a specific target. We selected the ThT aptamer using graphene oxide assisted SELEX and a low-cost Open qPCR instrument. We optimized, minimized, and characterized the best aptamer candidate against ThT. The aptamer, ThT dye, and the enzymatic strand displacement amplification (SDA) were used in a label-free approach to detect the micro RNA miR-215 in saliva and serum. The aptamer confers higher specificity than intercalating dyes but without expensive covalently modified DNA probes. This isothermal, low-cost, simple method can detect both DNA and RNA. The target, miR-215, was detected with a limit of detection of 2.6 nM.

SUBMITTER: Islam MM

PROVIDER: S-EPMC7900183 | biostudies-literature | 2021 Feb

REPOSITORIES: biostudies-literature

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Graphene oxide assisted light-up aptamer selection against Thioflavin T for label-free detection of microRNA.

Islam Md Mamunul MM Ghielmetti Victoria Michele VM Allen Peter B PB

Scientific reports 20210222 1

We selected an aptamer against a fluorogenic dye called Thioflavin T (ThT). Aptamers are single-stranded DNA that can bind a specific target. We selected the ThT aptamer using graphene oxide assisted SELEX and a low-cost Open qPCR instrument. We optimized, minimized, and characterized the best aptamer candidate against ThT. The aptamer, ThT dye, and the enzymatic strand displacement amplification (SDA) were used in a label-free approach to detect the micro RNA miR-215 in saliva and serum. The ap ...[more]

PMID: 33619372

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