Bottom-Up Signal Boosting with Fractal Nanostructuring and Primer Exchange Reaction for Ultrasensitive Detection of Cancerous Exosomes

Dual-antibody functionalized transistor biosensor for specific diagnosis of liver cancer

Selectively and sensitively detecting specific exosomal markers is critical for early diagnosis of liver cancer. However, identifying specific exosomal biomarkers and establishing accurate, convenient detection methods remain challenging. In this study, we used bioinformatics to identify the higher levels of EpCAM and GPC-3 proteins on liver cancer exosomes. These markers were used to create a dual-antibody functionalized transistor biosensor for precise detection of liver cancer exosomes. The techniques exhibited outstanding specificity and sensitivity. Detection thresholds in PBS and simulated plasma were established at 20 particles/μL and 47 particles/μL, respectively, facilitating the distinction of liver cancer cell-derived exosomes from those originating from various other cancer cells. Furthermore, in clinical samples testing, this approach not only distinguished clinical samples among liver cancer patients and healthy individuals, but also demonstrated the ability to differentiate liver cancer from other types of tumors, achieving a precision and accuracy rate of 100 %. The developed biosensor demonstrates excellent potential for clinical application and this work offers a promising and effective approach for cancer diagnosis.

Balancing performance and stability characteristics in organic electrochemical transistor

Nowadays organic electrochemical transistors (OECTs) are becoming a promising platform for bioelectronics and biosensing due to its biocompatibility, high sensitivity and selectivity, low driving voltages, high transconductance and flexibility. However, the existing problems associated with degradation processes within the OECT during long-term operation hinder their widespread implementation. Moreover, trade-offs often arise between OECT transconductance and speed, fast ion transport and electron mobility, electrochemical stability and sensitivity, cycling stability and signal amplification, and other metrics. Ensuring high performance characteristics and achieving enhanced stability in OECTs are distinct strategies that do not always align, as progress in one aspect often necessitates a trade-off with the other. This dynamic arises from the need to find a balance between reversible and irreversible processes in the behavior of OECT active layers, and providing simultaneously favorable conditions for ion and electron transport and their efficient charge coupling. This review article systematically summarizes the phenomenological and physical-chemical aspects associated with factors and mechanisms that determine both performance and long-term stability of OECT, paying special attention to the consideration of existing and promising approaches to extend the OECT lifespan, while maintaining (or even increasing) high effectiveness of its operation.

Dual-color fluorescence detection of tumor-derived extracellular vesicles using a specific and serum-stable membrane-fusion approach

Tumor-derived extracellular vesicles (tEVs), which are essential mediators for cell-to-cell communication during tumorigenesis and tumor development, have demonstrated significant diagnostic potential in cancer liquid biopsy, particularly through biomarkers like membrane proteins and inner microRNAs. However, traditional detection methods such as ELISA and qRT-PCR encounter challenges with low sensitivity and specificity, complex procedures, and high costs. Although emerging biosensors have been developed, these methods are limited to detecting a single type of tEV biomarker, which may result in misdiagnoses due to false-positive or false-negative signals. Herein, we introduce a specific and serum-stable membrane-fusion approach (SSMFA) capable of simultaneously detecting tEV proteins and microRNAs via dual-color fluorescence analysis. In this strategy, the established epithelial cell adhesion molecule (EpCAM) aptamer-modified serum-stable membrane-fusion liposome (AptSMFL) is labeled with fluorescence resonance energy transfer (FRET) dye pairs, which can specifically recognize EpCAM-overexpressed tEVs and induce serum-stable membrane fusion, allowing the quantification of EpCAM protein levels through red fluorescence changes resulting from FRET alterations. Meanwhile, SSMFA facilitates efficient transfection of the CRISPR/Cas13a probe into tEVs to analyze the levels of microRNA-21 (miR-21) in EpCAM-positive tEVs via green fluorescence detection. When tested on serum samples from hepatocellular carcinoma models, the SSMFA exhibited minimal sample volume requirement and rapid assay time (2 h) to effectively achieve accurate quantification of both tEV EpCAM protein and miR-21 levels. Additionally, this dual-biomarker detection method showed a strong correlation with tumor burden and significantly improved cancer diagnostic accuracy (AUC = 0.98), underscoring the potential of SSMFA as a promising tEV-based liquid biopsy assay for cancer diagnosis.

Ultrasensitive Profiling of Plasma Extracellular Vesicles for Breast Cancer Subtyping with a High-Curvature Antifouling Nanoarray

Profiling of plasma extracellular vesicles (EVs) has long been hampered by their insufficient capture and assay sensitivity due to the high background of complex matrices. To address this challenge, we develop a high-curvature antifouling nanoarray electrochemical assay (eCAN) to enable ultrasensitive and specific profiling of plasma EVs for the accurate subtyping of breast cancer. This assay leverages a three-in-one multifunctional hierarchical antifouling nanofilm to improve EV capture, minimize nonspecific adsorption, and facilitate three-dimensional deposition of tyramine for signal amplification. These advantages allow the eCAN to achieve a sensitivity of up to 56 particles/mL (near a single-EV level), showing high specificity and anti-interference. The eCAN can differentiate EV subpopulations across different breast cancer cells and monitor their phenotypic changes. This assay allows accurate diagnosis and subtyping of breast cancer (AUC = 1.000) through direct profiling of EVs in undiluted plasma from a pilot cohort and provides a promising tool for precise diagnosis of cancers in clinical settings.

Electric Field-Resistant Bubble-Enhanced Wash-Free Profiling of Extracellular Vesicle Surface Markers

Efficient profiling of circulating extracellular vesicles (EVs) benefits noninvasive cancer diagnosis and therapeutic monitoring, but is technically hampered by tedious isolation, multistep washing, and poor sensitivity. Here, we report multifunctional bubbles that enable self-separation, wash-free, single-step, and ultrasensitive profiling of EV surface markers in plasma samples for early diagnosis and treatment monitoring of lung cancer. In this assay, the buoyancy-dominated bubble is electric field-resistant, allowing EV-responsive release of electroactive probes for electrohydrodynamic nanoshearing force-enhanced hybridization, self-separation from the electrode interface for minimizing noise in electrochemical measurements, and one-step wash-free EV profiling. This assay achieves sensitivity near a single-EV level, shows high specificity against nontarget EVs, and tracks EV phenotypic changes induced by drugs. We further show that this technology can classify plasma samples (n = 111) between cancer patients and noncancer controls with accuracies >95%, enable accurate early diagnosis via machine learning, and monitor pre/post-surgery efficacy with higher accuracy over routine clinical serum markers. This bubble-driven one-step EV assay provides a promising wash-free quantitative tool to enable clinical precision liquid biopsies.

Exosomes in Autoimmune Diseases: A Review of Mechanisms and Diagnostic Applications

Exosomes, small extracellular vesicles secreted by various cell types, have emerged as key players in the pathophysiology of autoimmune diseases. These vesicles serve as mediators of intercellular communication, facilitating the transfer of bioactive molecules such as proteins, lipids, and nucleotide. In autoimmune diseases, exosomes have been implicated in modulating immune responses, oxidative stress, autophagy, gut microbes, and the cell cycle, contributing to disease initiation, progression, and immune dysregulation. Recent advancements in exosome isolation techniques and their molecular characterization have paved the way for exploring their clinical potential as biomarkers and therapeutic targets. This review focuses on the mechanisms by which exosomes influence autoimmune disease development and their potential clinical applications, particularly in diagnosis. The role of exosomes in autoimmune diseases, including systemic lupus erythematosus (SLE), rheumatoid arthritis (RA), type 1 diabetes mellitus (T1DM), inflammatory bowel disease (IBD), and Sjögren's syndrome (SS), is discussed in relation to their involvements in antigen presentation, T-cell activation, and the induction of inflammatory pathways. Additionally, exosome-based biomarkers offer promising non-invasive diagnostic tools for early diagnostic, disease monitoring, and therapeutic response assessment. However, challenges such as standardization of exosome isolation protocols and validation of their clinical significance remain. This review highlights the potential of exosomes as both diagnostic biomarkers and therapeutic targets in autoimmune diseases, emphasizing the need for further research to overcome current limitations and fully harness their clinical value.

Highly Sensitive Flow Cytometry Biosensor with a High Signal-to-Background Ratio for FEN1 Analysis via Solid-Phase Interface-Mediated Primer Exchange Reaction Amplification

Flap endonuclease 1 (FEN1) is a specific enzyme capable of recognizing and cleaving triplex DNA structures and releasing 5'-flap fragments. It plays a crucial role in the DNA metabolism of cells, participating in DNA replication and the repair of damaged DNA. Additionally, FEN1 is overexpressed in various tumor tissues, promoting tumor progression and drug resistance through different regulatory mechanisms. However, few significant advancements have been made in sensitive analytical methods for detecting FEN1. Herein, in this study, we present a highly sensitive flow cytometry biosensor with solid-phase interface-mediated primer exchange reaction amplification (FCsperA) for FEN1 analysis. By comparing homogeneous PER amplification (h-PER), we found that solid-phase interface-mediated PER amplification (s-PER) effectively suppressed background signals, leading to a higher signal-to-background (S/B) ratio exceeding ∼46-fold when FEN1 was at 1 × 10-3 U/μL. Combining the high efficiency of s-PER, the strong suppression of background signals, and the highly precise flow cytometry assay, FCsperA showed high sensitivity, with a limit of detection (LOD) for FEN1 of 2.53 × 10-6 U/μL. Notably, FCsperA exhibited high selectivity and exceptional anti-interference ability, making it applicable for detecting FEN1 in cells and serum samples. The outstanding performance of FCsperA allowed for sensing FEN1 in ∼10 cancer cells. Additionally, FCsperA demonstrated the potential for screening inhibitors of FEN1.

Ultrasensitive detection of cancer-associated nucleic acids and mutations by primer exchange reaction-based signal amplification and flow cytometry

The detection of cancer-associated nucleic acids and mutations through liquid biopsy has emerged as a highly promising non-invasive approach for early cancer detection and monitoring. In this study, we report the development of primer exchange reaction (PER) based signal amplification strategy that enables the rapid, sensitive and specific detection of nucleic acids bearing cancer specific single nucleotide mutations using flow cytometry. Using micrometer size beads as support for immobilizing oligonucleotides and programmable PER assembly for target oligonucleotide recognition and fluorescence signal amplification, we demonstrated the versatile detection of target nucleic acids including KRAS oligonucleotide, fragmented mRNAs, and miR-21. Moreover, our detection system can discriminate single base mutations frequently occurred in cancer-associated genes including KRAS, PIK3CA and P53 from cell extracts and circulating tumor DNAs (ctDNAs). The detection is highly sensitive, with a limit of detection down to 27 fM without pre-amplification. In view of a clinical application, we demonstrate the detection of single mutations after extraction and pre-amplification of ctDNAs from the plasma of breast cancer patients. Importantly, our detection strategy enabled the detection of single KRAS mutation even in the presence of 1000-fold excess of wild type (WT) DNA using multi-color flow cytometry detection approach. Overall, our strategy holds immense potential for clinical applications, offering significant improvements for early cancer detection and monitoring.

An Amplification-Free Digital Assay Based on Primer Exchange Reaction-Mediated Botryoidal-Like Fluorescent Polystyrene Dots to Detect Multiple Pathogenic Bacteria

Multiple and ultrasensitive detection of pathogenic bacteria is critical but remains a challenge. Here, we introduce a digital assay for multiplexed and target DNA amplification-free detection of pathogenic bacteria using botryoidal-like fluorescent polystyrene dots (PS-dots), which were first prepared through the hybridization reaction between primer exchange reaction chains and polystyrene nanospheres that encapsulated polymer dots for signal preamplification. The pathogenic bacteria's DNA was cleavaged by the argonaute (Ago) protein-mediated multiple and precise cleavage reactions, where the obtained target sequences bridged the magnetic beads (MBs) and botryoidal-like PS-dots via a hybridization reaction, and the fluorescent MB-botryoidal PS-dot complexes were utilized as digital probes based on colors and sizes for digital encoding. An artificial-intelligence-fluorescent microsphere counting algorithm was applied to identify and count the fluorescent MBs for digital readout. This digital assay combined the ultrabright botryoidal-like PS-dots with Clostridium butyricum Ago's precise enzyme cleavage properties, achieving simultaneous detection of three pathogenic bacteria with a linearity range from 102 to 106 CFU/mL without target DNA amplification within 1.5 h. This digital assay has also been applied to detect aquatic and clinical samples with accepted accuracy (98%), which offers an avenue for a next-generation multiplexed digital platform for pathogenic bacteria analysis.

Recent advances in the applications of DNA frameworks in liquid biopsy: A review

Cancer is one of the serious threats to public life and health. Early diagnosis, real-time monitoring, and individualized treatment are the keys to improve the survival rate and prolong the survival time of cancer patients. Liquid biopsy is a potential technique for cancer early diagnosis due to its non-invasive and continuous monitoring properties. However, most current liquid biopsy techniques lack the ability to detect cancers at the early stage. Therefore, effective detection of a variety of cancers is expected through the combination of various techniques. Recently, DNA frameworks with tailorable functionality and precise addressability have attracted wide spread attention in biomedical applications, especially in detecting cancer biomarkers such as circulating tumor cells (CTCs), exosomes and circulating tumor nucleic acid (ctNA). Encouragingly, DNA frameworks perform outstanding in detecting these cancer markers, but also face some challenges and opportunities. In this review, we first briefly introduced the development of DNA frameworks and its typical structural characteristics and advantages. Then, we mainly focus on the recent progress of DNA frameworks in detecting commonly used cancer markers in liquid-biopsy. We summarize the advantages and applications of DNA frameworks for detecting CTCs, exosomes and ctNA. Furthermore, we provide an outlook on the possible opportunities and challenges for exploiting the structural advantages of DNA frameworks in the field of cancer diagnosis. Finally, we envision the marriage of DNA frameworks with other emerging materials and technologies to develop the next generation of disease diagnostic biosensors.

Buoyant Metal-Organic Framework Corona-Driven Fast Isolation and Ultrasensitive Profiling of Circulating Extracellular Vesicles

Accurately assaying tumor-derived circulating extracellular vesicles (EVs) is fundamental in noninvasive cancer diagnosis and therapeutic monitoring but limited by challenges in efficient EV isolation and profiling. Here, we report a bioinspired buoyancy-driven metal-organic framework (MOF) corona that leverages on-bubble coordination and dual-encoded surface-enhanced Raman scattering (SERS) nanotags to streamline rapid isolation and ultrasensitive profiling of plasma EVs in a single assay for cancer diagnostics. This integrated bubble-MOF-SERS EV assay (IBMsv) allows barnacle-like high-density adhesion of MOFs on a self-floating bubble surface to enable fast isolation (2 min, near 90% capture efficiency) of tumor EVs via enhanced EV-MOF binding. Also, IBMsv harnesses four-plexed SERS nanotags to profile the captured EV surface protein markers at a single-particle level. Such a sensitive assay allows multiplexed profiling of EVs across five cancer types, revealing heterogeneous EV surface expression patterns. Furthermore, the IBMsv assay enables cancer diagnosis in a pilot clinical cohort (n = 55) with accuracies >95%, improves discrimination between cancer and noncancer patients via an algorithm, and monitors the surgical treatment response from hepatocellular carcinoma patients. This assay provides a fast, sensitive, streamlined, multiplexed, and portable blood test tool to enable cancer diagnosis and response monitoring in clinical settings.

Catalytic Assembly of DNAzyme Integrates with Primer Exchange Reaction (CDiPER) for Highly Sensitive Detection of MicroRNA

MicroRNAs (miRNAs) have significant regulatory functions in the modulation of gene expression, making them essential biomarkers for the diagnosis and prognosis of diseases. Nevertheless, the identification of miRNA poses significant difficulty in terms of its low abundance, necessitating sensitive and reliable approaches. Herein, we develop a simple approach, termed Catalytic assembly of DNAzyme integrates with Primer Exchange Reaction (CDiPER), for reliable and sensitive miRNA detection through the target recognition-triggered DNAzyme assembly and primer exchange reaction (PER) strategy. In this method, target miRNA can precisely bind with a specifically designed hairpin probe (H probe) to induce the conformation changes of the H probe, releasing DNAzyme sections to activate the PER process for signal amplification and fluorescence signal production. The established method displays a high dynamic range of over 6 orders of magnitude and a low detection limit of 312 aM. The created method has a number of unique advantages, such as (i) a better sensitivity than existing systems using PER for signal amplification as a result of its integration with the target recognition-triggered DNAzyme assembly and (ii) streamlined operating procedures. Further, the technology was used to detect the expression of miRNA in collected clinical samples from diabetes mellitus patients, revealing that miRNA was decreased in patients and demonstrating the significant clinical promise of the method.

All-in-one detection of breast cancer-derived exosomal miRNA on a pen-based paper chip

Exosomal microRNAs (miRNAs) play a pivotal role in intercellular communication, regulating gene expression in target cells, and hold significant promise as cancer biomarkers for early detection and screening. However, achieving precise and viable detection of exosomal miRNAs remains a challenge. This paper proposes an all-in-one detection strategy for breast cancer-derived exosomal miRNA-21 on a pen-based paper chip (PPC). The PPC is constructed using a modified automatic pen and lateral flow assay (LFA), which results in a cost-effective fabrication process. The user only needs to add the sample and trigger the top of the self-contained PPC after a period of time to complete the entire detection process. To enhance the sensitivity of exosomal miRNA testing, an enzyme-free catalyzed hairpin assembly (CHA) is further introduced, enabling highly sensitive detection of miRNA-21 with a limit of detection (LOD) of 25 fmol. Additionally, the detection of miRNAs in differentially-expressed cells and clinical samples has also been successfully achieved with high specificity. Overall, the proposed PPC provides an effective tool for detecting early cancer, monitoring diseases, and establishing point of care testing (POCT).

Polydopamine-assisted aptamer-carrying tetrahedral DNA microelectrode sensor for ultrasensitive electrochemical detection of exosomes

BACKGROUND

Exosomes are nanoscale extracellular vesicles (30-160 nm) with endosome origin secreted by almost all types of cells, which are considered to be messengers of intercellular communication. Cancerous exosomes serve as a rich source of biomarkers for monitoring changes in cancer-related physiological status, because they carry a large number of biological macromolecules derived from parental tumors. The ultrasensitive quantification of trace amounts of cancerous exosomes is highly valuable for non-invasive early cancer diagnosis, yet it remains challenging. Herein, we developed an aptamer-carrying tetrahedral DNA (Apt-TDNA) microelectrode sensor, assisted by a polydopamine (PDA) coating with semiconducting properties, for the ultrasensitive electrochemical detection of cancer-derived exosomes.

RESULTS

The stable rigid structure and orientation of Apt-TDNA ensured efficient capture of suspended exosomes. Without PDA coating signal amplification strategy, the sensor has a linear working range of 102-107 particles mL-1, with LOD of ~ 69 exosomes and ~ 42 exosomes for EIS and DPV, respectively. With PDA coating, the electrochemical signal of the microelectrode is further amplified, achieving single particle level sensitivity (~ 14 exosomes by EIS and ~ 6 exosomes by DPV).

CONCLUSIONS

The proposed PDA-assisted Apt-TDNA microelectrode sensor, which integrates efficient exosome capture, sensitive electrochemical signal feedback with PDA coating signal amplification, provides a new avenue for the development of simple and sensitive electrochemical sensing techniques in non-invasive cancer diagnosis and monitoring treatment response.

Exosome-tuned MOF signal amplifier boosting tumor exosome phenotyping with high-affinity nanostars

The natural phospholipid structure imparts exosomes with not only cargo protection, but rich sites for coordination with metal-organic frameworks (MOFs) to assemble functional nanocomplexes, such as signal amplifiers. Here, we exploit exosomes to tune MOF signal amplifiers (Exo-MOF) for ultrasensitive phenotyping of tumor-derived exosomes (tExo) based on self-driven coordination assembly and high-affinity nanostars. Exo-MOF leverages the specific coordination interaction between exosome and MOF that cages abundant redox molecules to assemble a super-redox signal amplifier. Moreover, the dispersed immuno-magnetic nanostars, which are assembled with antibodies on the surface of Au nanostars-coated magnetic nanoparticles, allow for rapid capturing of target tExo, addressing the limited mass transfer on electrode surface. Both Exo-MOF and high-affinity nanostars orchestrate the ultrahigh sensitivity (1 particle per 100 μL, higher than that no Exo-MOF by at least 10-fold), specificity and speed of the sensor in tExo detection. Such a sensitive strategy allows profiling tExo across seven cancer types, and revealing the distinct exosomal surface expression patterns. Further, the Exo-MOF sensor accurately distinguishes cancer patients from healthy individuals in a clinical cohort, and provides new opportunities for functional materials assembly and precision diagnostics.

Multivalent DNA Flowers for High-Performance Isolation, Detection, and Release of Tumor-Derived Extracellular Vesicles

Tumor-derived extracellular vesicles (T-EVs) hold great promise for understanding cancer biology and improving cancer diagnostics and therapeutics. Herein, we developed multivalent DNA flowers (DFs) containing repeated and equidistant EpCAM aptamers for the efficient isolation of T-EVs. The multivalent aptamer chains in DFs had good flexibility to adapt to the surface morphology of T-EVs and achieved multivalent ligand-receptor interactions, thus showing enhanced isolation ability compared to monovalent aptamers. Compared with other materials for isolation of EVs, DFs were generated by rolling circle amplification (RCA) and self-assembled into microspheres in a one-pot reaction, and the recognition molecules (aptamers) were directly replicated and assembled during the RCA reaction instead of chemical modification and immobilization on the surface of solid materials. Moreover, as optically transparent biomaterials, the content of EpCAM+ EVs could be directly reflected via membrane-based hydrophobic assembly of signaling modules in DFs@EpCAM+ EVs complex, and we found that the amount of EpCAM+ EVs showed greater accuracy in cancer diagnosis than total EVs (88.3 vs 69.7%) and was also higher than the clinically commonly used marker carcinoembryonic antigen (CEA) (88.3 vs 76.7%). In addition, T-EVs could be released by lysis of DFs with the nuclease, gently and easily, keeping high intact and activity of EVs for downstream biological function studies. These results demonstrated that DFs are efficient and nondestructive tools for isolation, detection, and release of T-EVs.

Design strategies and advanced applications of primer exchange reactions in biosensing: A review

Early disease diagnosis relies on the sensitive detection and imaging of biomarkers. Signal amplification is one of the most commonly used methods to improve detection sensitivity. Primer exchange reaction (PER) is a novel signal amplification technique that has garnered attention because of its simple and sensitive features. The classical PER involves a single catalytic hairpin, which enables the attachment of custom sequences to the primer chain, generating a long repeat sequence that can bind numerous signaling molecules and achieve powerful signal amplification. Currently, numerous PER-based signal amplification strategies are available that can improve detection sensitivity and promote the development of the signal amplification field. This review focuses on the mechanism of typical PER, the diversification of PER, and PER-based biosensors for various targets. Finally, the challenges and prospects of PER development are discussed.

CRISPR/dCas9-Mediated Specific Molecular Assembly Facilitates Genotyping of Mutant Circulating Tumor DNA

Breakthroughs in circulating tumor DNA (ctDNA) analysis are critical in tumor liquid biopsies but remain a technical challenge due to the double-stranded structure, extremely low abundance, and short half-life of ctDNA. Here, we report an electrochemical CRISPR/dCas9 sensor (E-dCas9) for sensitive and specific detection of ctDNA at a single-nucleotide resolution. The E-dCas9 design harnesses the specific capture and unzipping of target ctDNA by dCas9 to introduce a complementary reporter probe for specific molecular assembly and signal amplification. By efficient homogeneous assembly and interfacial click reaction, the assay demonstrates superior sensitivity (up to 2.86 fM) in detecting single-base mutant ctDNA and a broad dynamic range spanning 6 orders of magnitude. The sensor is also capable of measuring 10 fg/μL of a mutated target in excess of wild-type ones (1 ng/μL), equivalent to probing 0.001% of the mutation relative to the wild type. In addition, our sensor can monitor the dynamic expression of cellular genomic DNA and allows accurate analysis of blood samples from patients with nonsmall cell lung cancer, suggesting the potential of E-dCas9 as a promising tool in ctDNA-based cancer diagnosis.

Bioorthogonal Microbubbles with Antifouling Nanofilm for Instant and Suspended Enrichment of Circulating Tumor Cells

Integrating clinical rare cell enrichment, culture, and single-cell phenotypic profiling is currently hampered by the lack of competent technologies, which typically suffer from weak cell-interface collision affinity, strong nonspecific adsorption, and the potential uptake. Here, we report cells-on-a-bubble, a bioinspired, self-powered bioorthogonal microbubble (click bubble) that leverages a clickable antifouling nanointerface and a DNA-assembled sucker-like polyvalent cell surface, to enable instant and suspended isolation of circulating tumor cells (CTCs) within minutes. Using this biomimetic engineering strategy, click bubbles achieve a capture efficiency of up to 98%, improved by 20% at 15 times faster over their monovalent counterparts. Further, the buoyancy-activated bubble facilitates self-separation, 3D suspension culture, and in situ phenotyping of the captured single cancer cells. By using a multiantibody design, this fast, affordable micromotor-like click bubble enables suspended enrichment of CTCs in a cohort (n = 42) across three cancer types and treatment response evaluation, signifying its great potential to enable single-cell analysis and 3D organoid culture.