RESUMO
The ability to simply, selectively, and sensitively detect low numbers of miRNAs in clinical samples is highly valuable but remains a challenge. In this work, we present a novel miRNA detection system by using the elaborately designed hairpin switch, where the T7 primer, template, target recognize sequence, and light-up RNA aptamer template are edited and embedded in one single-stranded DNA hairpin structure. In the beginning, the hairpin switch maintained the hairpin structure 1, in which the ds promoter of T7 polymerase was disrupted, thus the transcription reaction of T7 polymerase was inhibited. After binding to the target, the hairpin switch 1 was unfolded and turned to the hairpin structure 2. This switch initiates the in vitro T7 transcription reaction, producing plenty of RNA transcripts containing RNA aptamers. Consequently, transcribed tremendous RNA aptamers lighted up the fluorophore for quantitative analysis. Compared with the existing T7 polymerase-based amplification system, this strategy exhibits several advantages, including simplicity, convenience, and high selectivity and sensitivity. The experimental results demonstrated that we could achieve the quantification of miRNA in buffer and complex biological samples.
Assuntos
Aptâmeros de Nucleotídeos , MicroRNAs , Aptâmeros de Nucleotídeos/genética , DNA de Cadeia Simples , Corantes Fluorescentes , Proteínas Fúngicas , MicroRNAs/genética , NucleotidiltransferasesRESUMO
A novel microcapsule composed of Cu9S5 and SnS2 quantum dots (QDs)/carbon nanotubes (CNTs) prepared through a microfluidic approach was developed for a Li-ion battery anode. CNTs enhance the conductivity, while pores in the shell facilitate electrolyte penetration, and void in the microcapsule buffers the volume change. The microcapsule-based anode displayed stable capacity, a Coulombic efficiency of 99.9%, and reversible rate-performance at temperatures of -10 °C and 45 °C, which are significant for developing high-performance energy-storage materials and battery systems.