Photocontrolled Nanopipette Biosensor for ATP Gradient Electroanalysis of Single Living Cells

Abstract

Emerging nanopipette tools have demonstrated substantial potential for advanced single-cell analysis, which plays vital roles from fundamental cellular biology to biomedical diagnostics. Highly recyclable nanopipettes with easy and quick regeneration are of special interest for precise and multiple measurements. However, existing recycle strategies are generally plagued by operational complexity and limited efficiency. Light, acting in a noncontact way, should be the ideal external stimulus to address this issue. Herein, we present the photocontrolled nanopipette capable of probing cellular adenosine triphosphate (ATP) gradient at single-cell level with good sensitivity, selectivity, and reversibility, which stems from the use of ATP-specific azobenzene (Azo)-incorporated DNA aptamer strands (AIDAS) and thereby the sensible transduction of variable nanopore size by the ionic currents passing through the aperture. Photoisomerized conformational change of the AIDAS by alternative UV/vis light stimulation ensures its noninvasive regeneration and repeated detection. Inducement and inhibition of the cellular ATP could also be probed by this nanosensor.

Fluorescent Nanoscale Covalent Organic Frameworks with the Theoretically Matched Redox Potential of Fe3+/Fe2+ for Monitoring of Adenosine-5′-Triphosphate in Cells

“…The detection of Fe 3+ and ATP is of great value for regulating and integrating cellular metabolism. − Therefore, based on the effect of Fe 3+ on the excellent fluorescence properties of the NCOF and the complexation between ATP-Fe 3+ , the NCOF fluorescent probe was applied to the imaging of Fe 3+ and ATP in cells. First of all, the cytotoxicity verified that the cell activity could still maintain 90.44% after 48 h of incubation with cells even when NCOF was up to 200 μg/mL, indicating that the NCOF had good biocompatibility (Figure a).…”

Light‐Controlled Ionic/Molecular Transport through Solid‐State Nanopores and Nanochannels

“…[145] the nanopipette for single living cells analysis. [195][196][197][198] For example, a recyclable photocontrolled biosensor was demonstrated for sensitive detection of cellular ATP gradient according to the interactions between ATP and AZO-incorporated DNA aptamer strands, [197] resulting in the variations of the nanopore size and ionic current responses. The nanopipette-based sensing strategy provided a powerful analytical approach for the single living cell and brain neurochemistry research.…”

“…This work not only constructed a nanochannel‐based PEC biosensor, but also confirmed that the heterogeneous nanochannel‐semiconductor structure can be applied for the advanced biochemical system with higher stabilities and enhanced sensitivities. Meanwhile, they constructed series of electrochemical biosensors based on the nanopipette for single living cells analysis [195–198] . For example, a recyclable photocontrolled biosensor was demonstrated for sensitive detection of cellular ATP gradient according to the interactions between ATP and AZO‐incorporated DNA aptamer strands, [197] resulting in the variations of the nanopore size and ionic current responses.…”

Specially Resolved Single Living Cell Perfusion and Targeted Fluorescence Labeling Based on Nanopipettes

“…First, carrier-mediated delivery systems using viral carrier, extracellular vesicle, cationic polymers, liposomes, etc. − Second, mechanical delivery techniques based on ultrasound, heating, electric punching, etc. − Among them, electrochemical strategy has been considered as a powerful technology for single cell manipulation with minuscule invasiveness. In particular, glass nanopipettes have shown significant promise for the analysis of single living cells, with potential for targeting subcellular regions. − Nanopipettes provide a simple way for the manipulation of single living cells at the nanoscale level, which has been used in imaging, ion transfer, intracellular delivery and extraction, membrane disruption, etc. − The nanopipette-assisted method allows the simultaneous delivery of various fluorescent probes into a single cell to realize super-resolution imaging by adjusting the concentration and applied potentials . Compared to traditional cellular delivery strategies, nanopipette-based manipulation conquers the deficiencies such as low cell viabilities and long incubation times. , For example, Li’s group delivered individual proteins to a defined position in single cells based on nanopipettes .…”