Lab on a Chip最新文献

{"title":"An enhanced heat transfer method based on the electrocapillary effect of gallium-based liquid metal†","authors":"Liyu Dai, Xiaomin Wu, Yiqing Guo, Huimin Hou, Zhifeng Hu, Yukai Lin and Zhiping Yuan","doi":"10.1039/D4LC00791C","DOIUrl":"10.1039/D4LC00791C","url":null,"abstract":"<p >As electronic products become smaller and more powerful, there is an increasing need for effective heat dissipation. An effective heat exchange method is necessary for the equipment to function reliably in a compact space. To tackle the limitations of current microfluidic cooling technology, including difficulty in manufacturing, maintenance, and cost reduction, a heat exchange method with a simple system is proposed in this work. This method is based on the electrocapillary effect, using eutectic gallium–indium alloy droplets with high thermal conductivity, surface tension, and controllability as the basic unit. An electric field is applied to generate unevenly distributed charges in the electric double layer on the droplet surface, thereby creating a surface tension gradient that can drive the surrounding solution to flow. Simultaneously, the oscillation of the droplet can also intensify the disturbance of the solution. The violent disturbance of the solution causes the heat transfer mode to change from conduction to convective heat transfer and greatly reduces the thermal resistance, resulting in a substantial increase in heat flux. For this heat transfer method, the temperature distribution and flow characteristics of the solution in low-frequency oscillating and direct-current-biased alternating current electric fields are studied, and the effect of voltage, frequency, and the number of droplets on heat transfer enhancement is clarified. Compared with conduction without internal disturbance, the heat flux can be increased by up to 110% based on the combined effect of two droplets. This work provides a solution for enhancing the heat transfer of microfluidics.</p>","PeriodicalId":85,"journal":{"name":"Lab on a Chip","volume":" 24","pages":" 5318-5327"},"PeriodicalIF":6.1,"publicationDate":"2024-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142680270","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 multimodal digital microfluidic testing platform for antibody-producing cell lines†","authors":"Jeremy T. Lant, Jurgen Frasheri, Taehong Kwon, Camille M. N. Tsang, Bingyu B. Li, Sheldon Decombe, Alexandros A. Sklavounos, Samin Akbari and Aaron R. Wheeler","doi":"10.1039/D4LC00816B","DOIUrl":"10.1039/D4LC00816B","url":null,"abstract":"<p >In recent years, monoclonal antibodies (mAbs) have become a powerful tool in the treatment of human diseases. Currently, over 100 mAbs have received approval for therapeutic use in the US, with wide-ranging applications from cancer to infectious diseases. The predominant method of producing antibodies for therapeutics involves expression in mammalian cell lines. In the mAb production process, significant optimization is typically done to maximize antibody titres from cells grown in bioreactors. Therefore, systems that can miniaturize and automate cell line testing (<em>e.g.</em>, viability and antibody production assays) are valuable in reducing therapeutic mAb development costs. Here we present a novel platform for cell line optimization for mAb production using digital microfluidics. The platform enables testing of cell culture samples in 6–8 μL droplets with semi-automated viability, media pH, and antibody production assays. This system provides a unique bridge between cell growth and productivity metrics, while minimizing culture volume requirements for daily testing. We propose that this technology and its future iterations has the potential to help reduce the time-to-market and development costs of antibody-producing cell lines.</p>","PeriodicalId":85,"journal":{"name":"Lab on a Chip","volume":" 24","pages":" 5398-5412"},"PeriodicalIF":6.1,"publicationDate":"2024-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142674586","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":"Pervaporation-driven electrokinetic energy harvesting using poly(dimethylsiloxane) microfluidic chips†","authors":"Hrishikesh Pingulkar, Cédric Ayela and Jean-Baptiste Salmon","doi":"10.1039/D4LC00831F","DOIUrl":"10.1039/D4LC00831F","url":null,"abstract":"<p >Electrokinetic energy harvesting from evaporation-driven flows in porous materials has recently been the subject of numerous studies, particularly with the development of nanomaterials with high conversion efficiencies. The configuration in which the energy conversion element is located upstream of the element which passively drives the evaporative flow has rarely been studied. However, this configuration offers the possibility of increasing the harvested energy simply by increasing the evaporation surface area and/or the hydraulic resistance of the energy conversion element. In this work, we investigate this configuration with poly(dimethylsiloxane) (PDMS) chips playing the role of <em>artificial leaves</em> driving a pervaporation-induced flow through a polystyrene colloid plug in a submillimetre tube for the energy conversion. With an appropriate design of the venation of the PDMS leaves, we report the first experimental evidence of electrokinetic energy conversion from pervaporation-induced flows, which increases with the pervaporation area. We also provide new insights by demonstrating that this increase is limited by cavitation within the PDMS leaves, which occurs systematically as soon as the water pressure inside the leaf reaches <em>P</em><small>_leaf</small> ≃ 0 bar. Whatever the cavitation threshold, this phenomenon imposes an intrinsic limit on this configuration, underlining the need for innovative strategies to improve the harvesting of electrokinetic energy by evaporation.</p>","PeriodicalId":85,"journal":{"name":"Lab on a Chip","volume":" 24","pages":" 5328-5337"},"PeriodicalIF":6.1,"publicationDate":"2024-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142708572","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":"Stitched textile-based microfluidics for wearable devices†","authors":"Martin Hanze, Andrew Piper and Mahiar Max Hamedi","doi":"10.1039/D4LC00697F","DOIUrl":"10.1039/D4LC00697F","url":null,"abstract":"<p >Thread-based microfluidics, which rely on capillary forces in threads for liquid flow, are a promising alternative to conventional microfluidics, as they can be easily integrated into wearable textile-based biosensors. We present here advanced textile-based microfluidic devices fabricated by machine stitching, using only commercially available textiles. We stitch a polyester “Coolmax®” yarn with enhanced wicking abilities into both hydrophobic fabric and hydrophobically treated stretchable fabric, that serve as non-wicking substrates. In doing so we construct textile microfluidics capable of performing a wide variety of functions, including mixing and separation in 2D and 3D configurations. Furthermore, we integrate a stitched microfluidic device into a wearable T-shirt and show that this device can collect, transport, and detect sweat from the wearer's skin. These can also be machine-washed, making them inherently reusable. Finally, we integrate electrochemical sensors into the textile-based microfluidic devices using stitched gold-coated yarns to detect analytes in the microfluidic yarns. Our stitched textile-based microfluidic devices hold promise for wearable diagnostic applications. This novel, bottom-up fabrication using machine stitching is scalable, reproducible, low-cost, and compatible with the existing textile manufacturing industry.</p>","PeriodicalId":85,"journal":{"name":"Lab on a Chip","volume":" 1","pages":" 28-40"},"PeriodicalIF":6.1,"publicationDate":"2024-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11599943/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142724305","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":"Detecting telomerase activity at the single-cell level using a CRISPR-Cas12a-based chip†","authors":"Yateng Jiang, Yanping Wang, Wen Luo, Xiaowei Luan, Zhibin Zhang, Yongchun Pan, Bangshun He, Yanfeng Gao and Yujun Song","doi":"10.1039/D4LC00619D","DOIUrl":"10.1039/D4LC00619D","url":null,"abstract":"<p >The intimate association between telomerase activity and cancer has driven the exploration of diverse methodologies for its precise detection. However, detecting telomerase activity at the single-cell level remains a significant challenge. Herein, we present a MOF–DNA barcode-amplified CRISPR-Cas12a strategy integrated with a single-cell microfluidic chip for ultrasensitive detection of telomerase activity. DNA-functionalized UiO-66 nanoparticles act as signal transducers, effectively converting telomerase activity into DNA activation strands, which subsequently trigger the <em>trans</em>-cleavage activity of CRISPR-Cas12a. This amplification-based assay could be integrated with a microfluidic chip to enable highly sensitive detection of telomerase activity at the single-cell level, offering promising advancements in early cancer diagnosis.</p>","PeriodicalId":85,"journal":{"name":"Lab on a Chip","volume":" 1","pages":" 49-56"},"PeriodicalIF":6.1,"publicationDate":"2024-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142714863","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":"Automated Dynamic Inlet Microfluidics (ADIM) system: cost-effective biaxial nanoliter droplet on demand generation platform and its application in agglutination assays†","authors":"Abdul Basit Zia and Ian G. Foulds","doi":"10.1039/D4LC00643G","DOIUrl":"10.1039/D4LC00643G","url":null,"abstract":"<p >The paper demonstrates an adaptation of a Prusa Mini+ 3D printer through the integration of 3D printed modules, creating a system capable of producing varied droplets from multiple Eppendorf tubes. Building upon our previous model, this system enhances calibration methodology enabling any fused deposition modeling (FDM) printer to produce mono-disperse droplets (coefficient of variance (CV%) &lt;2% for train of 100 droplets) with 6900 assays per hour rate. The cost of the developed system is 85% lower than that of existing droplet generation solutions on the market, and 30% more economical than the previous iteration of the system. Additionally, the system's utility in quantification of agglutination assays is highlighted using image analysis, capable of distinguishing between agglutinated and non-agglutinated samples. By offering significant savings and ease of use, this system aims to lower the barriers to entry for microfluidic research, potentially broadening the scope of scientific exploration and application in this field.</p>","PeriodicalId":85,"journal":{"name":"Lab on a Chip","volume":" 1","pages":" 57-68"},"PeriodicalIF":6.1,"publicationDate":"2024-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142737831","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":"Advancing scalable and controllable multi-core droplet generation with double disturbance flow focusing†","authors":"Chen Li, Kai Mu, Fangsheng Huang, Zhiqiang Zhu and Ting Si","doi":"10.1039/D4LC00758A","DOIUrl":"10.1039/D4LC00758A","url":null,"abstract":"<p >At present, a variety of active and passive methods for generating microdroplets with different morphologies are available. Microcapsules with multi-core or compartment structures not only exhibit characteristics such as encapsulation, isolation, and leak prevention, but also possess specific functions, including enhanced buffering performance and superior heat transfer characteristics. Nevertheless, the high-throughput manufacturing of controllable multi-core droplets remains a significant challenge, constrained by the complexity of the equipment, the inconvenience of control, and the high cost. This study introduces a novel flow focusing method that integrates biphasic excitation to produce uniformly distributed double-emulsion droplets with a controlled number of cores at high throughput. The breakup of coaxial jets has been studied under different excitation frequencies, amplitudes, and flow rates of inner and outer liquids, with a particular focus on the change of the droplet morphology as the controllable parameter varies. By applying excitation to both the inner and outer jets in the weak coupling mode, our technique exhibits promising outcomes in achieving uniformity and controllability in the number of cores of the generated droplets. The scaling laws of the compound droplet size have been obtained, providing theoretical guidance for practical applications. The proposed biphasic excitation approach enhances the precision and efficiency of droplet generation processes in a range of applications, including pharmaceuticals, biotechnology, and materials science.</p>","PeriodicalId":85,"journal":{"name":"Lab on a Chip","volume":" 24","pages":" 5413-5420"},"PeriodicalIF":6.1,"publicationDate":"2024-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142685403","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":"SERS-based pump-free microfluidic chip sensor for highly sensitive competitive immunoassay of cortisol in human sweat†","authors":"Siyue Xiong, Chushu Zhu, Chengxuan Wang, Peitao Dong and Xuezhong Wu","doi":"10.1039/D4LC00858H","DOIUrl":"10.1039/D4LC00858H","url":null,"abstract":"<p >Cortisol, known as the “stress hormone”, is secreted by the adrenal cortex. Measuring cortisol levels in body fluids is essential for evaluating stress levels, adrenal function, hormone imbalance, and psychological well-being. Early diagnosis and management of related conditions depend on this measurement. A rapid detection method that combines immunoassay and surface-enhanced Raman scattering (SERS) technology has become widely used in bioanalysis, offering benefits such as fast detection, high throughput, integrated microsystems, and high specificity. This study introduces a pump-free microfluidic chip integrating a solid-state SERS substrate to detect trace amounts of cortisol in bodily fluids through immunoassay. The method relies on a competitive reaction between cortisol and SERS tags with cortisol antigens immobilized on gold nanostructured substrates in a microfluidic environment. Two detection channels are used to provide controls and enhance measurement efficiency and accuracy. Solid-state gold nanostructured substrates offer a larger surface area for antibody capture and act as SERS-active substrates, which significantly enhance the Raman signal and improve the microsystem's sensitivity and applicability. Driven by a capillary pump, the sample can be loaded within 60 seconds, with the entire detection process taking less than 10 min, significantly reducing the detection time. Results indicate that the detection limit for cortisol is 10 pg mL<small>⁻¹</small>, meeting clinical biomarker thresholds. The integrated SERS microfluidic chip shows great promise as an analytical tool for the rapid and sensitive diagnosis of cortisol in bodily fluids.</p>","PeriodicalId":85,"journal":{"name":"Lab on a Chip","volume":" 24","pages":" 5384-5397"},"PeriodicalIF":6.1,"publicationDate":"2024-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142674498","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":"Observing root growth and signalling responses to stress gradients and pathogens using the bi-directional dual-flow RootChip†","authors":"Claudia Allan, Yiling Sun, Stephen C. Whisson, Michael Porter, Petra C. Boevink, Volker Nock and Claudia-Nicole Meisrimler","doi":"10.1039/D4LC00659C","DOIUrl":"10.1039/D4LC00659C","url":null,"abstract":"<p >Plants respond to environmental stressors with adaptive changes in growth and development. Central to these responses is the role of calcium (Ca<small>²⁺</small>) as a key secondary messenger. Here, the bi-directional dual-flow RootChip (bi-dfRC) microfluidic platform was used to study defence signalling and root growth. By introducing salinity as sodium chloride (NaCl) treatment <em>via</em> a multiplexed media delivery system (MMDS), dynamic gradients were created, mimicking natural environmental fluctuations. Signal analysis in <em>Arabidopsis thaliana</em> plants showed that the Ca<small>²⁺</small> burst indicated by the G-CaMP3 was concentration dependent. A Ca<small>²⁺</small> burst initiated in response to salinity increase, specifically within the stele tissue, for 30 seconds. The signal then intensified in epidermal cells directly in contact with the stressor, spreading directionally towards the root tip, over 5 minutes. Inhibition of propidium iodide (PI) stain transport through the xylem was observed following salinity increase, contrasting with flow observed under control conditions. The interaction of <em>Phytophthora capsici</em> zoospores with <em>A. thaliana</em> roots was also studied. An immediate directional Ca<small>²⁺</small> signal was observed during early pathogen recognition, while a gradual, non-directional increase was observed in Orp1_roGFP fluorescent H<small>₂</small>O<small>₂</small> levels, over 30 min. By adjusting the dimensions of the bi-dfRC, plants with varying root architectures were subjected to growth analysis. Growth reduction was observed in <em>A. thaliana</em> and <em>Nicotiana benthamiana</em> roots when exposed to salinity induced by 100 mM NaCl, while <em>Solanum lycopersicum</em> exhibited growth increase over 90 minutes at the same NaCl concentration. Furthermore, novel insights into force sensing in roots were gained through the engineering of displaceable pillars into the bi-dfRC channel. These findings highlight the vital role of controlling fluid flow in microfluidic channels in advancing our understanding of root physiology under stress conditions.</p>","PeriodicalId":85,"journal":{"name":"Lab on a Chip","volume":" 24","pages":" 5360-5373"},"PeriodicalIF":6.1,"publicationDate":"2024-11-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.rsc.org/en/content/articlepdf/2024/lc/d4lc00659c?page=search","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142594925","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":"Optical tweezer-assisted cell pairing and fusion for somatic cell nuclear transfer within an open microchannel†","authors":"Yidi Zhang, Han Zhao, Zhenlin Chen, Zhen Liu, Hanjin Huang, Yun Qu, Yaowei Liu, Mingzhu Sun, Dong Sun and Xin Zhao","doi":"10.1039/D4LC00561A","DOIUrl":"10.1039/D4LC00561A","url":null,"abstract":"<p >Somatic cell nuclear transfer (SCNT), referred to as somatic cell cloning, is a pivotal biotechnological technique utilized across various applications. Although robotic SCNT is currently available, the subsequent oocyte electrical activation/reconstructed embryo electrofusion is still manually completed by skilled operators, presenting challenges in efficient manipulation due to the uncontrollable positioning of the reconstructed embryo. This study introduces a robotic SCNT-electrofusion system to enable high-precision batch SCNT cloning. The proposed system integrates optical tweezers and microfluidic technologies. An optical tweezer is employed to facilitate somatic cells in precisely reaching the fusion site, and a specific polydimethylsiloxane (PDMS) chip is designed to assist in positioning and pairing oocytes and somatic cells. Enhancement in the electric field distribution between two parallel electrodes by PDMS pillars significantly reduces the required external voltage for electrofusion/electrical activation. We employed porcine oocytes and porcine fetal fibroblasts for SCNT experiments. The experimental results show that 90.56% of oocytes successfully paired with somatic cells to form reconstructed embryos, 76.43% of the reconstructed embryos successfully fused, and 70.55% of these embryos underwent cleavage. It demonstrates that the present system achieves the robotic implementation of oocyte electrical activation/reconstructed embryo electrofusion. By leveraging the advantages of batch operations using microfluidics, it proposes an innovative robotic cloning procedure that scales embryo cloning.</p>","PeriodicalId":85,"journal":{"name":"Lab on a Chip","volume":" 23","pages":" 5215-5224"},"PeriodicalIF":6.1,"publicationDate":"2024-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142581171","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}