Engineering Biomimetic Biosensor Using Dual‐Targeting Multivalent Aptamer Regulated 3D DNA Walker Enables High‐Performance Detection of Heterogeneous Circulating Tumor Cells

Abstract

The phenotypic heterogeneity of circulating tumor cells (CTCs) and the nonspecific adsorption of background cells impede the effective and sensitive detection of rare CTCs. Although leukocyte membrane coating approach has a good antileukocyte adhesion ability and holds great promise for addressing the challenge of capture purity, its limited specificity and sensitivity prevent its use in the detection of heterogeneous CTCs. To overcome these obstacles, a biomimetic biosensor that integrated dual‐targeting multivalent aptamer/walker duplex functionalized biomimetic magnetic beads and an enzyme‐powered DNA walker signal amplification strategy is designed. As compared to conventional leukocyte membrane coating, the biomimetic biosensor achieves efficient and high purity enrichment of heterogeneous CTCs with different epithelial cell adhesion molecule (EpCAM) expression while minimizing the interference of leukocytes. Meanwhile, the capture of target cells can trigger the release of walker strands to activate an enzyme‐powered DNA walker, resulting in cascade signal amplification and the ultrasensitive and accurate detection of rare heterogeneous CTCs. Importantly, the captured CTCs remained viable and can be recultured in vitro with success. Overall, this work provides a new perspective for the efficient detection of heterogeneous CTCs by biomimetic membrane coating and paves the way for early cancer diagnosis.

Steric Hindrance-Mediated Enzymatic Reaction Enable Homogeneous Dual Fluorescence Indicators Aptasensing of Hepatocellular Carcinoma CTCs

“…Nevertheless, most of the existing systems demonstrated multiply modified materials or cascade amplifications to ensure the quantification of scarce CTCs. In contrast, this steric hindrance-mediated enzymatic reaction-assisted homogeneous method greatly simplified the procedure, which could meet the requirements for early diagnosis of HCC. − …”

Recent Progress in Electrochemical Biosensors Based on DNA-functionalized Nanomaterials

“…The inclusion of DNA within the sensor boosts the signal generated by the pendulum, thus enhancing sensitivity and precision [108]. Table 1 shows in vitro DNA functionalized electrochemical sensing devices for a variety of targets and the real samples [109][110][111][112][113][114][115][116].…”

A Fluorescence Light-Up 3D DNA Walker Driven and Accelerated by Endogenous Adenosine-5′-triphosphate for Sensitive and Rapid Label-Free MicroRNA Detection and Imaging in Living Cells

“…MicroRNAs (miRNAs) are a class of endogenous small noncoding RNAs that are involved in the post-transcriptional regulation of genes and affect a variety of biological processes in cells, thus achieving sensitive detection of miRNAs is crucial for the diagnosis and prognosis of a wide range of diseases. − Recently, three-dimensional (3D) DNA nanomachines with multiple binding sites have been widely used for miRNA detection and live cell imaging due to their enhanced reactivity by increasing the local concentration of reactants. , In general, the energy to operate the DNA nanomachines autonomously comes from DNA strands, − enzymes, , metal ions, , pH changes, , light, and entropy. , However, these approaches often require the introduction of external additives, which tend to increase the complexity of the experiment and the possibility of signaling errors. In this work, the endogenous ATP in cells as a driving force and accelerator of a 3D DNA walker effectively mitigates the interference caused by external substances and minimizes the likelihood of errors as well as reduces the time required for detection and imaging.…”