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Life‐like hierarchical architecture shows great potential for advancing intelligent biosensing, but modular expansion of its sensitivity and functionality remains a challenge. Drawing inspiration from intracellular liquid‐liquid phase separation, we discovered that a DNA‐encoded artificial cell with a liquid core (LAC) can enhance peroxidase‐like activity of Hemin and its DNA G‐quadruplex aptamer complex (DGAH) without substrate‐selectivity, unlike its gelled core (GAC) counterpart. The LAC is easily engineered as an ultrasensitive biosensing system, benefiting from DNA′s high programmability and unique signal amplification capability mediated by liquid‐liquid phase separation. As proof of concept, its versatility was successfully demonstrated by coupling with two molecular recognition elements to monitor tumor‐related microRNA and profile cancer cell phenotypes. This scalable design philosophy offers new insights into the design of next generation of artificial cells‐based biosensors. [ABSTRACT FROM AUTHOR]

Cell‐specific aptamers offer a powerful tool to study membrane receptors at the single‐molecule level. Most target receptors of aptamers are highly expressed on the cell surface, but difficult to analyze in situ because of dense distribution and fast velocity. Therefore, we herein propose a random sampling‐based analysis strategy termed ligand dilution analysis (LDA) for easily implemented aptamer‐based receptor study. Receptor density on the cell surface can be calculated based on a regression model. By using a synergistic ligand dilution design, colocalization and differentiation of aptamer and monoclonal antibody (mAb) binding on a single receptor can be realized. Once this is accomplished, precise binding site and detailed aptamer‐receptor binding mode can be further determined using molecular docking and molecular dynamics simulation. The ligand dilution strategy also sets the stage for an aptamer‐based dynamics analysis of two‐ and three‐dimensional motion and fluctuation of highly expressed receptors on the live cell membrane. [ABSTRACT FROM AUTHOR]

Abstract: The specific binding ability of DNA–lipid micelles (DLMs) can be increased by the introduction of an aptamer. However, supramolecular micellar structures based on self‐assemblies of amphiphilic DLMs are expected to demonstrate low stability when interacting with cell membranes under certain conditions, which could lead to a reduction in selectivity for targeting cancer cells. We herein report a straightforward cross‐linking strategy that relies on a methacrylamide branch to link aptamer and lipid segments. By an efficient photoinduced polymerization process, covalently linked aptamer–lipid units help stabilize the micelle structure and enhance aptamer probe stability, further improving the targeting ability of the resulting nanoassembly. Besides the development of a facile cross‐linking method, this study clarifies the relationship between aptamer–lipid concentration and the corresponding binding ability. [ABSTRACT FROM AUTHOR]

Aptamer binding characterization, including receptor density calculation, single-molecule colocalization, binding site determination, motion and fluctuation analysis, was performed with minimal probe and instrument requirements. Back Cover: Ligand Dilution Analysis Facilitates Aptamer Binding Characterization at the Single-Molecule Level (Angew. Keywords: Aptamers; Binding Site; Dilution; Fluorescent Probes; Motion Analysis EN Aptamers Binding Site Dilution Fluorescent Probes Motion Analysis 1 1 1 02/22/23 20230301 NES 230301 B A membrane-receptor-analysis method b termed ligand dilution analysis, which combines the concepts of single-molecule localization and random sampling, is reported by Yifan Lyu, Jianhui Jiang, Weihong Tan et al. in their Research Article (e202215387). [Extracted from the article]

Aptamer binding characterization, including receptor density calculation, single-molecule colocalization, binding site determination, motion and fluctuation analysis, was performed with minimal probe and instrument requirements. Aptamers, Binding Site, Dilution, Fluorescent Probes, Motion Analysis Keywords: Aptamers; Binding Site; Dilution; Fluorescent Probes; Motion Analysis EN Aptamers Binding Site Dilution Fluorescent Probes Motion Analysis 1 1 1 02/22/23 20230301 NES 230301 B A membrane-receptor-analysis method b termed ligand dilution analysis, which combines the concepts of single-molecule localization and random sampling, is reported by Yifan Lyu, Jianhui Jiang, Weihong Tan et al. in their Research Article (e202215387). [Extracted from the article]