Lab on a Chip最新文献

{"title":"Reversible bonding in thermoplastic elastomer microfluidic platforms for harvestable 3D microvessel networks†","authors":"Byeong-Ui Moon, Kebin Li, Lidija Malic, Keith Morton, Han Shao, Lauren Banh, Sowmya Viswanathan, Edmond W. K. Young and Teodor Veres","doi":"10.1039/D4LC00530A","DOIUrl":"10.1039/D4LC00530A","url":null,"abstract":"<p >Transplantable ready-made microvessels have therapeutic potential for tissue regeneration and cell replacement therapy. Inspired by the natural rapid angiogenic sprouting of microvessels <em>in vivo</em>, engineered injectable 3D microvessel networks are created using thermoplastic elastomer (TPE) microfluidic devices. The TPE material used here is flexible, optically transparent, and can be robustly yet reversibly bonded to a variety of plastic substrates, making it a versatile choice for microfluidic device fabrication because it overcomes the weak self-adhesion properties and limited manufacturing options of poly(dimethylsiloxane) (PDMS). By leveraging the reversible bonding characteristics of TPE material templates, we present their utility as an organ-on-a-chip platform for forming and handling microvessel networks, and demonstrate their potential for animal-free tissue generation and transplantation in clinical applications. We first show that TPE-based devices have nearly 6-fold higher bonding strength during the cell culture step compared to PDMS-based devices while simultaneously maintaining a full reversible bond to (PS) culture plates, which are widely used for biological cell studies. We also demonstrate the successful generation of perfusable and interconnected 3D microvessel networks using TPE–PS microfluidic devices on both single and multi-vessel loading platforms. Importantly, after removing the TPE slab, microvessel networks remain intact on the PS substrate without any structural damage and can be effectively harvested following gel digestion. The TPE-based organ-on-a-chip platform offers substantial advantages by facilitating the harvesting procedure and maintaining the integrity of microfluidic-engineered microvessels for transplant. To the best of our knowledge, our TPE-based reversible bonding approach marks the first confirmation of successful retrieval of organ-specific vessel segments from the reversibly-bonded TPE microfluidic platform. We anticipate that the method will find applications in organ-on-a-chip and microphysiological system research, particularly in tissue analysis and vessel engraftment, where flexible and reversible bonding can be utilized.</p>","PeriodicalId":85,"journal":{"name":"Lab on a Chip","volume":null,"pages":null},"PeriodicalIF":6.1,"publicationDate":"2024-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2024/lc/d4lc00530a?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142236824","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"SlipO2Chip – single-cell respiration under tuneable environments†","authors":"Yuan Cui, Milena De Albuquerque Moreira, Kristen E. Whalen, Laurent Barbe, Qian Shi, Klaus Koren, Maria Tenje and Lars Behrendt","doi":"10.1039/D4LC00420E","DOIUrl":"10.1039/D4LC00420E","url":null,"abstract":"<p >In disciplines like toxicology and pharmacology, oxygen (O<small>₂</small>) respiration is a universal metric for evaluating the effects of chemicals across various model systems, including mammalian and microalgal cells. However, for these cells the common practice is to segregate populations into control and exposure groups, which assumes direct equivalence in their responses and does not take into account heterogeneity among individual cells. This lack of resolution impedes our ability to precisely investigate differences among experimental groups with small or limited sample sizes. To overcome this barrier, we introduce SlipO<small>₂</small>Chip, an innovative glass microfluidic platform for precisely quantifying single-cell O<small>₂</small> respiration in the coordinated absence and presence of chemical solutes. SlipO<small>₂</small>Chip comprises a wet-etched fused silica channel plate on the top and a dry-etched borosilicate microwell plate at the bottom. The microwells are coated with Pt(<small>II</small>) <em>meso</em>-tetra(pentafluorophenyl)porphine (PtTFPP), an O<small>₂</small> sensing optode material and an O<small>₂</small>-independent reference dye. A custom 3D-printed holder facilitates the controlled horizontal movement (‘slipping’) of the channel plate over the microwell plate, thereby establishing or disrupting the fluid path over microwells. Collectively, these design elements enable the immobilization of single-cells in microwells, their exposure to controlled fluid flows, the coordinated opening and closing of microwells and repeated measurements of single-cell O<small>₂</small> respiration. Uniquely, by sequentially executing opening and closing it becomes possible to measure single-cell respiration prior to and after exposure to chemical solutes. In a proof-of-concept application, we utilized SlipO<small>₂</small>Chip to measure the impact of increasing exposures of the marine bacterial signal 2-heptyl-4-quinolone (HHQ) on the dark respiration of the diatom <em>Ditylum brightwellii</em> at single-cell resolution. Results revealed a concentration-dependent decrease in per-cell O<small>₂</small> dark respiration, with a maximum reduction of 40.2% observed at HHQ concentrations exceeding 35.5 μM, and a half-maximal effective concentration (<em>EC</em><small>₅₀</small>) of 5.8 μM, consistent with that obtained <em>via</em> conventional bulk respiration methods. The ability of SlipO<small>₂</small>Chip to sequentially assess the effects of chemical substances on single-cell O<small>₂</small> metabolism is advantageous for research where sample volumes are limited, such as clinical biopsies, studies involving rare microbial isolates, and toxicological studies aiming to address exposure effects while accounting for cell-to-cell variability.</p>","PeriodicalId":85,"journal":{"name":"Lab on a Chip","volume":null,"pages":null},"PeriodicalIF":6.1,"publicationDate":"2024-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2024/lc/d4lc00420e?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142236771","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Utilization of microdroplet as optical lens for Surface-Enhanced Raman Spectrometry (SERS) enhancement on localized silver nanoparticle-decorated porous silicon substrate","authors":"Chia-Wen Tsao, Zi-Yi Yang","doi":"10.1039/d4lc00550c","DOIUrl":"https://doi.org/10.1039/d4lc00550c","url":null,"abstract":"Surface-Enhanced Raman Spectroscopy (SERS) is a widely used analytical technique known for its high sensitivity and broad applicability. Despite its potential, SERS faces challenges related to detection sensitivity and reproducibility. This study proposes an innovative method to enhance SERS performance by employing water microdroplets as optical lenses on localized silver nanoparticle-decorated porous silicon (LocAg-PS) substrates. The hydrophobic nature of the LocAg-PS substrate not only ensures precise positioning of the microdroplet lenses on the silver nanoparticles grafted pad (AgNPs pad), but also form a plano-convex-like microdroplet lens for the focusing of the excitation laser and the collection of scattered light. Experimental results demonstrate that the use of microdroplet lenses enhances the SERS signal intensity and reproducibility, providing a rapid and cost-effective solution for advanced SERS analysis.","PeriodicalId":85,"journal":{"name":"Lab on a Chip","volume":null,"pages":null},"PeriodicalIF":6.1,"publicationDate":"2024-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142236772","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Improved Teflon lift-off for droplet microarray generation and single-cell separation on digital microfluidic chips†","authors":"Chuanjie Shen, Zhaoduo Tong, Xin Xu and Hongju Mao","doi":"10.1039/D4LC00630E","DOIUrl":"10.1039/D4LC00630E","url":null,"abstract":"<p >Droplet microarrays (DMAs) leveraging wettability differences are instrumental in digital immunoassays, single-cell analysis, and high-throughput screening. This study introduces an enhanced Teflon lift-off process to fabricate hydrophilic–hydrophobic patterns on a digital microfluidic (DMF) chip, thereby integrating DMAs with DMF technology. By employing DMF for droplet manipulation and utilizing wettability differences, the automated generation of high-throughput DMAs was achieved. The volume of the microdroplets ranged from picoliters to nanoliters. For droplets with a diameter of 150 μm, the array density reached up to 1282 cm<small>⁻²</small>. We systematically investigated the influence of various DMF parameters on the formation of DMAs and applied this technique to particle distribution, achieving a single-cell isolation rate of approximately 30%. We believe that this method will be a potent tool to enhance the capabilities of DMAs and DMF technology and extend their applicability across more fields.</p>","PeriodicalId":85,"journal":{"name":"Lab on a Chip","volume":null,"pages":null},"PeriodicalIF":6.1,"publicationDate":"2024-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142245945","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A three-dimensional vessel-on-chip model to study Puumala orthohantavirus pathogenesis.","authors":"Danny Noack,Anouk van Haperen,Mirjam C G N van den Hout,Eleanor M Marshall,Rosanne W Koutstaal,Vincent van Duinen,Lisa Bauer,Anton Jan van Zonneveld,Wilfred F J van IJcken,Marion P G Koopmans,Barry Rockx","doi":"10.1039/d4lc00543k","DOIUrl":"https://doi.org/10.1039/d4lc00543k","url":null,"abstract":"Puumala orthohantavirus (PUUV) infection in humans can result in hemorrhagic fever with renal syndrome. Endothelial cells (ECs) are primarily infected with increased vascular permeability as a central aspect of pathogenesis. Historically, most studies included ECs cultured under static two-dimensional (2D) conditions, thereby not recapitulating the physiological environment due to their lack of flow and inherent pro-inflammatory state. Here, we present a high-throughput model for culturing primary human umbilical vein ECs in 3D vessels-on-chip in which we compared host responses of these ECs to those of static 2D-cultured ECs on a transcriptional level. The phenotype of ECs in vessels-on-chip more closely resembled the in vivo situation due to higher similarity in expression of genes encoding described markers for disease severity and coagulopathy, including IDO1, LGALS3BP, IL6 and PLAT, and more diverse endothelial-leukocyte interactions in the context of PUUV infection. In these vessels-on-chip, PUUV infection did not directly increase vascular permeability, but increased monocyte adhesion. This platform can be used for studying pathogenesis and assessment of possible therapeutics for other endotheliotropic viruses even in high biocontainment facilities.","PeriodicalId":85,"journal":{"name":"Lab on a Chip","volume":null,"pages":null},"PeriodicalIF":6.1,"publicationDate":"2024-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142245366","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"3D-printed microfluidic–microwave device for droplet network formation and characterisation†","authors":"Kai Silver, Jin Li, Adrian Porch, William David Jamieson, Oliver Castell, Pantelitsa Dimitriou, Colin Kallnik and David Barrow","doi":"10.1039/D4LC00387J","DOIUrl":"10.1039/D4LC00387J","url":null,"abstract":"<p >Microfluidic–microwave devices (MMDs) have emerged as precision tools for the rapid, accurate, sensitive, and non-invasive characterisation of liquids in low-volumes. However, the fabrication of MMDs remains a significant challenge. This is due to the complexities associated with integrating fluidic ducts and electronic components. Herein, we present a versatile and economical 3D-printing approach using ducts filled with liquid metal as an electrical conductor. Cyclic olefin copolymer, polylactic acid, and polypropylene were identified as printable dielectric materials for MMD fabrication. Substrates of 3D-printed cyclic olefin copolymer exhibited the lowest loss tangent (0.002 at 2.7 GHz), making them suitable materials for high-frequency microwave devices. Liquid metal, specifically gallium–indium eutectic, was injected into the printed ducts to form electrically conductive microwave structures. Exemplary MMDs operating at 2 GHz integrated split-ring microwave resonators that serve as sensitive detection geometries able to measure changes in dielectric properties, with droplet-forming fluidic junctions and flow channels. The performance of 3D-printed MMDs for microwave droplet sensing was comprehensively evaluated. These devices were used in the formation and characterisation of water-in-oil emulsions, constructing definable lipid-segregated droplet interface bilayer (DIB) networks. This work indicates the feasibility of using 3D-printed manifolds for the rapid prototyping of customised MMDs, and also demonstrates the potential of MMDs as new analytical research tools in droplet-based materials and biochemistry studies.</p>","PeriodicalId":85,"journal":{"name":"Lab on a Chip","volume":null,"pages":null},"PeriodicalIF":6.1,"publicationDate":"2024-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2024/lc/d4lc00387j?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142235136","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Microfluidic sperm trap array for single-cell flagellar analysis with unrestricted 2D flagellar movement†","authors":"Kaiyu Wang, Antai Tao, Rongjing Zhang and Junhua Yuan","doi":"10.1039/D4LC00515E","DOIUrl":"10.1039/D4LC00515E","url":null,"abstract":"<p >Sperm capture techniques that immobilize sperm to halt their motility are essential for the long-term analysis of individual sperm. These techniques are beneficial in assisted reproductive technologies such as intracytoplasmic sperm injection (ICSI) by allowing selective screening of sperm. However, there is a notable lack of high-throughput and non-destructive sperm capture methods that allow the flagellum to beat freely, which is crucial for accurately reflecting the behavior of unfettered, freely swimming sperm. To bridge this gap, we introduce a novel microfluidic device specifically engineered to capture sperm without restricting flagellar motion. The design utilizes sperm's innate boundary-following behavior in both 3D and 2D environments to direct them into a capture zone. Once captured, the sperm head is restrained while the flagellum remains free to exhibit natural beating patterns. Utilizing this device, we explore the effects of hyperactivating agents, temperature, and their combined influence on the dynamics of bovine sperm flagella. The unrestricted flagellar motion offered by our device yields two prominent advantages: it mirrors the flagellar behavior of free-swimming sperm, ensuring research findings are consistent with natural sperm activity, and it prevents imaging overlap between the flagellum and the capture structures, simplifying the automation of flagellar tracking and analysis. This technological advancement facilitates the collection of waveform parameters along the entire flagellum, addressing inconsistencies that have arisen in previous research due to differing measurement sites, and enabling precise extraction of sperm behavioral properties.</p>","PeriodicalId":85,"journal":{"name":"Lab on a Chip","volume":null,"pages":null},"PeriodicalIF":6.1,"publicationDate":"2024-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142171019","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Andreas Manz – Pioneer, Mentor, Friend","authors":"Nicole Pamme and Petra S. Dittrich","doi":"10.1039/D4LC90072C","DOIUrl":"10.1039/D4LC90072C","url":null,"abstract":"<p >A graphical abstract is available for this content</p>","PeriodicalId":85,"journal":{"name":"Lab on a Chip","volume":null,"pages":null},"PeriodicalIF":6.1,"publicationDate":"2024-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142171018","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sample-to-answer centrifugal microfluidic droplet PCR platform for quantitation of viral load†","authors":"Lidija Malic, Liviu Clime, Byeong-Ui Moon, Christina Nassif, Dillon Da Fonte, Daniel Brassard, Ljuboje Lukic, Matthias Geissler, Keith Morton, Denis Charlebois and Teodor Veres","doi":"10.1039/D4LC00533C","DOIUrl":"10.1039/D4LC00533C","url":null,"abstract":"<p >Droplet digital polymerase chain reaction (ddPCR) stands out as a highly sensitive diagnostic technique that is gaining traction in infectious disease diagnostics due to its ability to quantitate very low numbers of viral gene copies. By partitioning the sample into thousands of droplets, ddPCR enables precise and absolute quantification without relying on a standard curve. However, current ddPCR systems often exhibit relatively low levels of integration, and the analytical process remains dependent on elaborate workflows for up-front sample preparation. Here, we introduce a fully-integrated system seamlessly combining viral lysis, RNA extraction, emulsification, reverse transcription (RT) ddPCR, and fluorescence readout in a sample-to-answer format. The system comprises a disposable microfluidic cartridge housing buffers and reagents required for the assay, and a centrifugal platform that allows for pneumatic actuation of liquids during rotation, enabling automation of the workflow. Highly monodisperse droplets (∼50 μm in diameter) are produced using centrifugal step emulsification and automatically transferred to an integrated heating module for target amplification. The platform is equipped with a miniature fluorescence imaging system enabling on-chip read-out of droplets after RT-ddPCR. We demonstrate sample-to-answer detection of SARS-CoV-2 N and E genes, along with RNase P endogenous reference, using hydrolysis probes and multiplexed amplification within single droplets for concentrations as low as 0.1 copy per μL. We also tested 14 nasopharyngeal swab specimens from patients and were able to distinguish positive and negative SARS-CoV-2 samples with 100% accuracy, surpassing results obtained by conventional real-time amplification.</p>","PeriodicalId":85,"journal":{"name":"Lab on a Chip","volume":null,"pages":null},"PeriodicalIF":6.1,"publicationDate":"2024-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2024/lc/d4lc00533c?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142171023","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A nanoporous hydrogel-based model to study chemokine gradient-driven angiogenesis under luminal flow†","authors":"Nidhi Mote, Sarah Kubik, William J. Polacheck, Brendon M. Baker and Britta Trappmann","doi":"10.1039/D4LC00460D","DOIUrl":"10.1039/D4LC00460D","url":null,"abstract":"<p >The growth of new blood vessels through angiogenesis is a highly coordinated process, which is initiated by chemokine gradients that activate endothelial cells within a perfused parent vessel to sprout into the surrounding 3D tissue matrix. While both biochemical signals from pro-angiogenic factors, as well as mechanical cues originating from luminal fluid flow that exerts shear stress on the vessel wall, have individually been identified as major regulators of endothelial cell sprouting, it remains unclear whether and how both types of cues synergize. To fill this knowledge gap, here, we created a 3D biomimetic model of chemokine gradient-driven angiogenic sprouting, in which a micromolded tube inside a hydrogel matrix is seeded with endothelial cells and connected to a perfusion system to control fluid flow rates and resulting shear forces on the vessel wall. To allow for the formation of chemokine gradients despite the presence of luminal flow, a nanoporous synthetic hydrogel that supports angiogenesis but limits the interstitial flow proved crucial. Using this system, we find that luminal flow and resulting shear stress is a major regulator of the speed and morphogenesis of angiogenic sprouting, whose action is mediated through changes in vascular permeability.</p>","PeriodicalId":85,"journal":{"name":"Lab on a Chip","volume":null,"pages":null},"PeriodicalIF":6.1,"publicationDate":"2024-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2024/lc/d4lc00460d?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142166545","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}