ACS Biomaterials Science & Engineering最新文献

{"title":"Enhanced Intracellular Delivery via Photochemical Internalization of Ultrasmall Fluorescent Core-Shell Aluminosilicate Nanoparticles.","authors":"Nada Naguib, Jacob A Erstling, James F Tallman, Ulrich B Wiesner","doi":"10.1021/acsbiomaterials.5c01199","DOIUrl":"https://doi.org/10.1021/acsbiomaterials.5c01199","url":null,"abstract":"<p><p>Current nanoparticle-based therapeutic systems for intracellular delivery face significant challenges due to endosomal entrapment, which prevents efficient cytosolic release of cargo and limits intracellular targeting. In this study, we develop methylene blue-functionalized ultrasmall fluorescent core-shell aluminosilicate nanoparticles (MB-Cy3-aC'dots) that overcome this limitation through controlled photochemical internalization (PCI). The nanoparticles synthesized in water with a hydrodynamic diameter of around 4-5 nm encapsulate cyanine 3 (Cy3) fluorophore in an aluminosilicate core, are coated with an oligomeric poly(ethylene glycol) (PEG) shell, and are surface-modified with methylene blue photosensitizer using two distinct PEG linker lengths. Photophysical characterization reveals that short-linker particles (MB-PEG4-Cy3-aC'dots) exhibit superior singlet oxygen quantum yields compared to long-linker variants (MB-PEG14-Cy3-aC'dots). However, cellular studies in HeLa cells demonstrate that the long-linker design achieved more effective cytosolic delivery despite lower quantum yields, indicating that using this configuration, membrane accessibility outweighs photophysical efficiency for PCI applications. Optimized treatment protocols using MB-PEG14-Cy3-aC'dots with 15 min red light illumination successfully convert punctate endosomal localization to diffuse cytoplasmic distribution while maintaining ∼80% cell viability. Live-cell imaging confirms efficient nuclear translocation and accumulation in nuclear structures, demonstrating the unique advantage of ultrasmall platforms for accessing restricted intracellular compartments. Mechanistic investigations reveal that the PCI treatment creates a permissive cellular environment, enabling sequential delivery of secondary nanoparticle populations potentially through endosomal fusion and membrane permeabilization pathways. The particle architecture (Cy3 core/MB surface) enables independent particle tracking and photosensitizer activation. These findings establish design principles for optimizing photosensitizer-nanoparticle conjugates and demonstrate the potential for multicargo delivery strategies with enhanced therapeutic versatility. The developed platform addresses critical limitations in intracellular targeting and provides a foundation for advancing precision nanomedicine applications requiring controlled subcellular localization.</p>","PeriodicalId":8,"journal":{"name":"ACS Biomaterials Science & Engineering","volume":" ","pages":""},"PeriodicalIF":5.5,"publicationDate":"2025-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145074066","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Real-Time Monitoring of the Formation and Culture of Hybrid Cell-Microbiomaterial Spheroids Using Non-Faradaic Electrical Impedance Spectroscopy.","authors":"Maria G Fois, Seppe Bormans, Thijs Vandenryt, Alexander P M Guttenplan, Yousra Alaoui Selsouli, Clemens van Blitterswijk, Zeinab Tahmasebi Birgani, Stefan Giselbrecht, Pamela Habibović, Ronald Thoelen, Roman K Truckenmüller","doi":"10.1021/acsbiomaterials.5c00402","DOIUrl":"https://doi.org/10.1021/acsbiomaterials.5c00402","url":null,"abstract":"<p><p>Cellular spheroids are considered a popular option for modeling healthy and diseased tissues <i>in vitro</i> and as injectable therapies. The formation and culture of spheroids can make use of different three-dimensional (3D) culture platforms, but the spheroids' analysis often has to rely on endpoint assays. In this study, we propose a microfluidic bioreactor to culture and nondestructively monitor human mesenchymal stem cell (hMSC) spheroids over time using non-Faradaic electr(ochem)ical impedance spectroscopy (EIS). For this, an array of porous microwells thermoformed from ion track-etched thin films and a pair of sensing electrodes from transparent indium tin oxide are integrated into the flow and culture chamber of the bioreactor. To measure the spheroid's electrical properties, the electrodes are connected to a frequency response analyzer (FRA), with a multiplexer in between to enable the operation of more than one bioreactor at the FRA at the same time. We find differences between the complex resistance/impedance and/or capacitance data of a reference condition without cells, a two-dimensional (2D) hMSC culture, hMSC spheroids, and hybrid spheroids aggregated from hMSCs and titanium or hydroxyapatite microparticles. We also found differences between different culture durations. These results suggest that our device can sense the presence and spatial arrangement of cells and micro(sized) biomaterials as a function of time.</p>","PeriodicalId":8,"journal":{"name":"ACS Biomaterials Science & Engineering","volume":" ","pages":""},"PeriodicalIF":5.5,"publicationDate":"2025-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145079136","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Nanoneedles in Biomedicine: Precision-Engineered Platforms for Theranostic Applications.","authors":"Narendran Sekar, Mathana Vetrivel P, Anisha Kabir, Kaviya Vijayalakshmi Babunagappan, Roey Elnathan, Swathi Sudhakar","doi":"10.1021/acsbiomaterials.5c00757","DOIUrl":"https://doi.org/10.1021/acsbiomaterials.5c00757","url":null,"abstract":"<p><p>Cell engineering holds immense potential for treating complex diseases but is limited by immunogenic responses, low targeting potential, and high costs. Vertical nanoneedles, precisely engineered with a high aspect ratio, have emerged as a promising delivery vehicle to overcome these problems for minimally invasive drug delivery and cellular stimulation. This review critically examines recent advances in the design, fabrication, and application of nanoneedles for various purposes, with a primary focus on gene and drug delivery, biosensing, and cellular differentiation. Key findings highlight how the nanoneedles help in the transport of cell-impermeable biological molecules in a minimally invasive way for their efficient function in therapeutics or biosensing applications and their limitations. These applications extend to improving gene therapy and cellular-based treatments, making them a versatile tool in regenerative medicine.</p>","PeriodicalId":8,"journal":{"name":"ACS Biomaterials Science & Engineering","volume":" ","pages":""},"PeriodicalIF":5.5,"publicationDate":"2025-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145074052","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Gelatin Methacryloyl Hydrogel-Coated Poly(ε-caprolactone) Microfibrous Membrane as a Friendly Blood-Contacting Material.","authors":"Yu Zhang, Xiangbo An, Ruitao Cha, Min Xiao, Pai Zhang, Ting Ma, Chunliang Zhang","doi":"10.1021/acsbiomaterials.5c01249","DOIUrl":"https://doi.org/10.1021/acsbiomaterials.5c01249","url":null,"abstract":"<p><p>The electrospun microfibrous membrane (EMM), as a blood-contacting material, holds great potential that promotes vascular tissue regeneration. However, EMM suffers from quick thrombosis. Hydrogel coating offers facile preparation and customizable functionality, which can improve the antithrombosis and endothelialization of the EMM. Here, a gelatin methacryloyl<i>/N</i>, <i>N</i>-methylene bis(acrylamide) (GelMA/MBA) hydrogel-coated poly(ε-caprolactone) microfibrous membrane (GM@PCL) was prepared conveniently by electrospinning/one-step coating. The structure and stability of the GM hydrogel coating were evaluated. The effects of the GM hydrogel coating on the antithrombotic properties and endothelialization of GM@PCL were studied. The introduction of the MBA improved the stability of the GM hydrogel coating due to the formation of dual cross-linking networks. The GM hydrogel coating endowed GM@PCL with excellent hydrophilicity and improved its antithrombosis by reducing protein adsorption, platelet adhesion, and red blood cell adhesion in a rabbit arteriovenous circulation model. The abundant arginine-glycine-aspartic acid sequences in the GM hydrogel coating promoted the adhesion and growth of endothelial cells on GM@PCL, achieving a higher endothelialization rate (98.1%) than that of PCL (66.9%) within 72 h. This work presents a promising and feasible one-step coating strategy that simultaneously addresses the challenges of thrombosis and endothelialization associated with microfiber-based blood-contacting materials and cardiovascular devices.</p>","PeriodicalId":8,"journal":{"name":"ACS Biomaterials Science & Engineering","volume":" ","pages":""},"PeriodicalIF":5.5,"publicationDate":"2025-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145038700","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Modeling Uterine Fibroids Using Bioengineered Hydrogels.","authors":"Allison K Moses, Miriam Tamaño-Blanco, Erika Moore","doi":"10.1021/acsbiomaterials.5c01026","DOIUrl":"https://doi.org/10.1021/acsbiomaterials.5c01026","url":null,"abstract":"<p><p>Uterine fibroids are the most common gynecological tumors, characterized by excessive production of extracellular matrix. Despite their prevalence, the cellular mechanisms governing fibroid growth remain poorly understood. Current in vitro models for fibroids do not replicate the complex 3D tissue mechanics, structure, and extracellular matrix components of fibroids, which may limit our understanding of fibroid pathogenesis. To address this gap, we aimed to develop a 3D in vitro model to mimic aspects of the fibroid microenvironment. By encapsulating human uterine fibroblasts in poly(ethylene glycol) (PEG)-based hydrogels comprising collagen- and fibronectin-derived peptides, this model allows for incorporation of fibroid cellular components, extracellular matrix components, and fibroid or myometrial tissue stiffness. Due to its mechanistic role in fibroblast activation and subsequent extracellular matrix production seen in fibroids, we treated uterine fibroblasts with transforming growth factor beta 3 (TGF-β3) to demonstrate quantification of fibrotic markers observed in fibroids. Here, we establish that human uterine fibroblasts increase α smooth muscle actin, extracellular matrix proteins, and cell elongation, as well as high metabolic activity and matrix remodeling in PEG-based hydrogels in response to TGF-β3. This research represents a physiologically relevant in vitro platform to investigate uterine fibroblast function within a 3D environment that mimics uterine fibroids, with the potential to advance our understanding of the cellular and molecular mechanisms driving fibroid growth and development.</p>","PeriodicalId":8,"journal":{"name":"ACS Biomaterials Science & Engineering","volume":" ","pages":""},"PeriodicalIF":5.5,"publicationDate":"2025-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145032378","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Violacein-Loaded Outer Membrane Vesicles from <i>Salmonella enterica</i> Exhibit Potent Anti-Melanoma Activity <i>in Vitro</i> and <i>in Vivo</i>.","authors":"Genesy Pérez Jorge, Marco Gontijo, Marina Flóro E Silva, Raquel Bester Liszbinski, Renata Spagolla Napoleão Tavares, Cyro von Zuben de Valega Negrão, Carlismari Oliveira Grundmann, Isabella Carolina Rodrigues Dos Santos Goes, Lilian de Oliveira Coser, Elizabeth Bilsland, Francisca Janaína Soares Rocha, Monica Tallarico Pupo, Selma Giorgio, Sandra Martha Gomes Dias, Fausto Almeida, Marcelo Brocchi","doi":"10.1021/acsbiomaterials.5c00933","DOIUrl":"https://doi.org/10.1021/acsbiomaterials.5c00933","url":null,"abstract":"<p><p>Violacein exhibits antitumor activity, indicating potential for future clinical application. However, an efficient delivery system is required for the clinical use of this hydrophobic compound. Effective delivery systems can enhance the solubility and bioavailability of hydrophobic compounds like violacein, facilitating its clinical application for antitumor therapy. Recent studies have demonstrated that outer membrane vesicles (OMVs) can serve as nanocarriers. This article constitutes the first report to present both <i>in vivo</i> and <i>in vitro</i> investigations of OMVs derived from a hypervesiculating mutant of <i>Salmonella enterica</i> Typhimurium as a delivery vehicle for violacein. In this study, <i>S. enterica</i> Typhimurium Δ<i>tolRA</i> (with a hypervesiculated phenotype) was transformed with a plasmid encoding the violacein biosynthesis operon. OMVs and violacein-loaded OMVs were isolated, characterized, and used in the treatment of murine melanoma. We assessed the cytotoxic effect of these violacein-loaded OMVs in both two-dimensional (2D) and three-dimensional (3D) cell cultures. Violacein-loaded OMVs reduced melanoma cell viability (IC₅₀: 9.30 × 10⁸ vesicles/mL) and delivered violacein in melanoma cells. Additionally, tumor regression was associated with treating tumor-bearing mice with violacein-loaded OMVs or nonviolacein-loaded OMVs (5 × 10⁹ vesicles/mouse). The antitumor response was linked to the accumulation of M1-type macrophages in the tumor microenvironment and the overexpression of mRNA for antitumor mediators Inducible Nitric Oxide Synthase, Tumor Necrosis Factor-alpha, and Interleukin-6 (iNOS, TNF-α, and IL-6). Our results suggest that OMVs can act as nanocarriers for highly hydrophobic agents and induce antitumor responses to eliminate tumors.</p>","PeriodicalId":8,"journal":{"name":"ACS Biomaterials Science & Engineering","volume":" ","pages":""},"PeriodicalIF":5.5,"publicationDate":"2025-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145032340","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Bioactive Coatings for Cardiovascular Stents: Modulating Immune Response for Enhanced Performance.","authors":"Subham Preetam, Richa Mishra, Shailendra Thapliyal, Sarvesh Rustagi, Ravi Kumar Deshwal, Seema Ramniwas, Archna Dhasmana, Bodour S Rajab, Saad Alghamdi, Sumira Malik","doi":"10.1021/acsbiomaterials.5c01166","DOIUrl":"https://doi.org/10.1021/acsbiomaterials.5c01166","url":null,"abstract":"<p><p>Cardiovascular disorders remain a leading cause of death worldwide, and the use of contemporary stents is paving the way for a profound shift in the field of cardiology. In the surgical process postimplantation, the graft or stent and host-immune interaction play a significant role in the healing process, thus it is a major challenge in healthcare. To address these challenges, recent advancements have introduced bioactive coatings with specialized modifications in stents to enhance their interaction with surrounding environment. These next-generation coatings are emphasizing strategies that reduce immune responses, that achieve up to ∼45% decrease in TNF-α expression and ∼60% reduction in IL-1β release in vitro, as well as ∼2.5-fold increase in M2/M1 macrophage ratio in animal models and promote vascular healing. In this review, we explore a range of coating materials, such as bioactive peptides, polymers, and composite systems, that have demonstrated the ability to elicit favorable biological responses while mitigating complications like inflammation, thrombosis, and restenosis. We explored the recent in vitro and in vivo research that shows the clinical potential of these coatings over times. Emerging innovations in this field highlight promising strategies for reducing inflammation and promoting endothelial healing in future cardiovascular stent designs.</p>","PeriodicalId":8,"journal":{"name":"ACS Biomaterials Science & Engineering","volume":" ","pages":""},"PeriodicalIF":5.5,"publicationDate":"2025-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145028570","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Engineering an Injectable Scaffold with Enhanced ECM Mimicry for Cell Delivery and Tissue Regeneration.","authors":"Shrikant S Kirwale, Ritika Jaiswal, Prajnadipti Sahu, Vagesh Verma, Sushil K Yadav, Aniruddha Roy","doi":"10.1021/acsbiomaterials.5c00958","DOIUrl":"https://doi.org/10.1021/acsbiomaterials.5c00958","url":null,"abstract":"<p><p>The development of biomimetic scaffolds that emulate the extracellular matrix (ECM) is critical for advancing cell-based therapies and tissue regeneration. This study reports the formulation of CHyCoGel, a novel injectable, ECM-mimetic hydrogel scaffold composed of chitosan, hyaluronic acid, chondroitin sulfate, and an amphiphilic stabilizer. CHyCoGel addresses key limitations of existing scaffolds, offering improved structural uniformity, injectability, and <i>in situ</i> gelation suitable for cell encapsulation and minimally invasive delivery. Primary dermal fibroblasts (PDFs) isolated from neonatal rat skin were grafted into CHyCoGel, which supported high cell viability, well-organized cytoskeletal structures, and modulation of genes involved in tissue remodeling, including α-SMA, fibronectin, Col1A1, and TGF-β. <i>In vivo</i> application of PDF-loaded CHyCoGel significantly enhanced wound healing, epithelialization, and the regeneration of skin appendages. Notably, CHyCoGel promoted angiogenesis by upregulating VEGF and facilitated balanced ECM remodeling through enhanced type I collagen expression with reduced total collagen accumulation. These findings highlight CHyCoGel's potential as a cytocompatible, bioactive scaffold capable of directing reparative cellular behavior and promoting structurally and functionally integrated tissue regeneration, particularly in chronic and complex wound settings.</p>","PeriodicalId":8,"journal":{"name":"ACS Biomaterials Science & Engineering","volume":" ","pages":""},"PeriodicalIF":5.5,"publicationDate":"2025-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145022464","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Controlling collagen I orientation on polyetheretherketone implants to improve epithelial sealing.","authors":"Ahmed Saad, Sangeeth Pillai, Simon D Tran, Faleh Tamimi, Conrado Aparicio, Marta Cerruti","doi":"10.1021/acsbiomaterials.5c00978","DOIUrl":"https://doi.org/10.1021/acsbiomaterials.5c00978","url":null,"abstract":"<p><p>Transcutaneous devices such as dental implants frequently fail due to infections at their interfaces with epithelial tissues. These infections are facilitated by the lack of integration between the devices and the surrounding soft tissues. This study aims to improve epithelial integration through surface modification of a transcutaneous implant material (polyetheretherketone (PEEK)). The modification involved covalent bonding of collagen via two distinct methods: (1) nonselective binding through any primary amines present on collagen using carbodiimide-based coupling and (2) site-specific binding to the free amine on the N-terminus of collagen molecules. The second approach preserves active sites responsible for interacting with integrins, crucial for epithelial cell adhesion, located near the C terminus. Both conjugation methods resulted in similar amounts of immobilized collagen; yet, surfaces with 2-PCA-based collagen conjugation exhibited 4 times more free amines. This indicates that fewer amines were used for conjugation in these samples, confirming that 2-PCA selectively binds collagen only through the N-terminus amines. Collagen-conjugated surfaces significantly enhanced HaCaT epithelial cell viability and adhesion compared to unmodified PEEK. Furthermore, 2-PCA-based conjugation resulted in a 2-fold increase in β4 subunit gene expression of integrin α6β4 (a key epithelial cell adhesion marker), higher integrin β4 immunofluorescence (IF) intensity, and over a 30% improvement in cell retention following mechanical detachment, compared to nonselective conjugation. These findings suggest that selective collagen conjugation on PEEK surfaces increases the accessibility of collagen domains responsible for binding with integrin receptors, which in turn improves epithelial cell attachment, offering a promising strategy for reducing infections and enhancing the longevity of transcutaneous devices.</p>","PeriodicalId":8,"journal":{"name":"ACS Biomaterials Science & Engineering","volume":" ","pages":""},"PeriodicalIF":5.5,"publicationDate":"2025-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145028543","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Versatile Droplet Microfluidic Platform Capable of Confining Preformed Spheroids in Hydrogel Microenvironments for Downstream Growth and Analysis.","authors":"Noura Ezzo, Thu H Nguyen, Carolyn L Ren, Evelyn K F Yim","doi":"10.1021/acsbiomaterials.5c01015","DOIUrl":"https://doi.org/10.1021/acsbiomaterials.5c01015","url":null,"abstract":"<p><p>Patient-derived tumor organoids (PDTOs) are promising 3D disease models for developing personalized treatment methods. However, conventional technologies for making PDTOs have limitations such as batch-to-batch variation and low throughput. Droplet microfluidics (DM), which utilizes uniform droplets generated in microchannels, has demonstrated potential for creating organoids due to its high-throughput and controllable parameters. However, most existing DM devices require a high initial cell count, on the order of 10,⁶ which is difficult to acquire with biopsy samples. A novel step-stone strategy is to encapsulate preformed spheroids in hydrogel droplets, creating a microenvironment supporting their future growth into organoids or for immediate analysis. While a similar strategy has been reported, the viability and uniformity of spheroids after encapsulation, which are important for continuous growth into organoids, were not examined. We present a DM device featuring a double-cross geometry chip to encapsulate preformed spheroids into hydrogel microparticles (HMPs) with a very low initial cell count (order of 10⁴) and ensuring high viability and uniformity of the spheroids in the recovered cross-linked HMPs. The preformed spheroids, 100-200 μm in diameter, were successfully encapsulated in well-defined HMPs. With contrasting viscosity hydrogels, a hydrodynamic focusing stream was created to leverage spheroids into their own droplets. Preformed spheroid encapsulation efficiency was affected by the width of the focusing stream and the quantity of spheroids at the inlet, with the best results reaching about 75% total encapsulation and 54% single spheroid encapsulation. Spheroid-laden HMPs were collected and cross-linked off-chip, where spheroids could continue to grow. The encapsulated spheroids maintained above 80% viability over 5 days of culture and retained uniformity with less than a 4% difference in diameter variation compared to pre-encapsulated spheroids. Ultimately, we demonstrated that preformed spheroid encapsulation using DM was a robust way to encapsulate a low sample size while maintaining viability and uniformity.</p>","PeriodicalId":8,"journal":{"name":"ACS Biomaterials Science & Engineering","volume":" ","pages":""},"PeriodicalIF":5.5,"publicationDate":"2025-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145013442","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}