Sensitive and Specific Y-Shaped Ratio Biosensor for Detecting Serum miR-18a: Potential Early Scanning Tool for Non-Small Cell Lung Cancer

Abstract

AbstractmiR-18a has been identified as a significantly expressed microRNA (miRNA) in non-small cell lung cancer (NSCLC) and plays a vital role in cancer cell transformation, metastasis, and carcinogenesis. Herein, a pair of binary probes from numerous probe pairs based on single nucleotide polymorphism analyses of miR-18a and miR-18b was first designed and screened to develop a Y-shaped ratio biosensor for accurate detection of serum miR-18a in NSCLC. The special structure of the binary probes combined with the hairpin showed strong specificity for miR-18a, which was confirmed by polyacrylamide gel electrophoresis assay and square wave voltammetry assay. Furthermore, it is beneficial to immobilize single-stranded DNA (ssDNA) probes due to the large specific surface area of nanoporous gold, thereby improving the sensitivity of the biosensor. The Y-shaped ratio biosensor exhibited a wide detection range and can quantify the concentration of miR-18a in the range of 10 fmol/L–100 pmol/L, with a limit of detection of 0.211 fmol/L (S/N = 3). Moreover, it exhibits excellent detection capabilities in serum samples since the biosensor showed a high selectivity toward the coexistence of miR-18a and miR-18b. Therefore, the prepared Y-shaped ratio biosensor is a highly sensitive and specific miR-18a detection tool, capable of identifying microscopic amounts of miR-18a in serum samples, providing great potential for early screening of NSCLC.

Single Particle Analysis-Enhanced DNA Walking Machine for Sensitive miRNA Detection

“…Molecular machines, such as dynein, myosin, and kinesin, perform various biological functions in living systems. − DNA walking machines, which benefit from the hybridization specificity, − functional programmability, , and structural diversity , of DNA, have been developed for the construction of various biosensors and provide significant stability, specificity, and predictability. Among them, three-dimensional (3D) DNA walking machines have attracted extensive attention due to their high surface-to-volume ratio, multidimensional spatial orientation, and high walking efficiency. − Wei’s team devised an innovative 3D DNA walking machine capable of independent and continuous traversal along the regeneration path, enabling the highly sensitive detection of the Ebola virus .…”

Proximity-Induced Bipedal DNA Walker for Accurately Visualizing microRNA in Living Cancer Cell

“…The utilization of CHA as the driving force of the DNA walker is easier to optimize the reaction conditions and is more suitable for living cell imaging analysis. MicroRNAs (miRNAs), which are a category of single-stranded endogenous, noncoding and small (approximately 22 nucleotides) RNA molecules, play crucial roles in regulating various biological processes. , Particularly, numerous researches have evidenced that the abnormal expression levels of miRNAs are closely associated with occurrence and development of various human diseases including cancer, revealing that miRNAs can serve as potential biomarkers for the prognosis and diagnosis of cancer. − Therefore, as a proof of concept, miRNA-34a, a biomarker of breast cancer, is chosen as the model system to demonstrate this approach. After the specific recognition of miRNA-34a by two DNA proximity probes, a stochastic bipedal DNA walker was formed, and it was capable of autonomously and progressively traversing on the surface of gold nanoparticles (AuNPs) through the CHA.…”