1
|
Wang Y, Wang Y, Wang X, Sun W, Yang F, Yao X, Pan T, Li B, Chu J. Label-free active single-cell encapsulation enabled by microvalve-based on-demand droplet generation and real-time image processing. Talanta 2024; 276:126299. [PMID: 38788384 DOI: 10.1016/j.talanta.2024.126299] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2024] [Revised: 05/01/2024] [Accepted: 05/20/2024] [Indexed: 05/26/2024]
Abstract
Droplet microfluidics-based single-cell encapsulation is a critical technology that enables large-scale parallel single-cell analysis by capturing and processing thousands of individual cells. As the efficiency of passive single-cell encapsulation is limited by Poisson distribution, active single-cell encapsulation has been developed to theoretically ensure that each droplet contains one cell. However, existing active single-cell encapsulation technologies still face issues related to fluorescence labeling and low throughput. Here, we present an active single-cell encapsulation technique by using microvalve-based drop-on-demand technology and real-time image processing to encapsulate single cells with high throughput in a label-free manner. Our experiments demonstrated that the single-cell encapsulation system can encapsulate individual polystyrene beads with 96.3 % efficiency and HeLa cells with 94.9 % efficiency. The flow speed of cells in this system can reach 150 mm/s, resulting in a corresponding theoretical encapsulation throughput of 150 Hz. This technology has significant potential in various biomedical applications, including single-cell omics, secretion detection, and drug screening.
Collapse
Affiliation(s)
- Yiming Wang
- Department of Precision Machinery and Precision Instrumentation, University of Science and Technology of China, Hefei, 230027, China; Key Laboratory of Precision Scientific Instrumentation of Anhui Higher Education Institutes, University of Science and Technology of China, Hefei, 230027, China
| | - Yousu Wang
- Department of Precision Machinery and Precision Instrumentation, University of Science and Technology of China, Hefei, 230027, China; Key Laboratory of Precision Scientific Instrumentation of Anhui Higher Education Institutes, University of Science and Technology of China, Hefei, 230027, China
| | - Xiaojie Wang
- Department of Precision Machinery and Precision Instrumentation, University of Science and Technology of China, Hefei, 230027, China; Key Laboratory of Precision Scientific Instrumentation of Anhui Higher Education Institutes, University of Science and Technology of China, Hefei, 230027, China
| | - Wei Sun
- Department of Precision Machinery and Precision Instrumentation, University of Science and Technology of China, Hefei, 230027, China; Key Laboratory of Precision Scientific Instrumentation of Anhui Higher Education Institutes, University of Science and Technology of China, Hefei, 230027, China
| | - Fengrui Yang
- MOE Key Laboratory for Membraneless Organelles and Cellular Dynamics, School of Life Sciences, University of Science and Technology of China, Hefei, 230026, China
| | - Xuebiao Yao
- MOE Key Laboratory for Membraneless Organelles and Cellular Dynamics, School of Life Sciences, University of Science and Technology of China, Hefei, 230026, China
| | - Tingrui Pan
- Department of Precision Machinery and Precision Instrumentation, University of Science and Technology of China, Hefei, 230027, China; Suzhou Institute for Advanced Research, University of Science and Technology of China, Suzhou, 215123, China
| | - Baoqing Li
- Department of Precision Machinery and Precision Instrumentation, University of Science and Technology of China, Hefei, 230027, China; Key Laboratory of Precision Scientific Instrumentation of Anhui Higher Education Institutes, University of Science and Technology of China, Hefei, 230027, China.
| | - Jiaru Chu
- Department of Precision Machinery and Precision Instrumentation, University of Science and Technology of China, Hefei, 230027, China; Key Laboratory of Precision Scientific Instrumentation of Anhui Higher Education Institutes, University of Science and Technology of China, Hefei, 230027, China
| |
Collapse
|
2
|
Zhao Z, Zhai H, Zuo P, Wang T, Xie R, Tian M, Song R, Xu X, Li Z. Image-activated pico-injection for single-cell analysis. Talanta 2024; 272:125765. [PMID: 38346358 DOI: 10.1016/j.talanta.2024.125765] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2023] [Revised: 01/29/2024] [Accepted: 02/06/2024] [Indexed: 03/17/2024]
Abstract
The addition of reagents into preformed droplets is a crucial yet intricate task in droplet-based applications where sequential reactions is required. Pico-injection offers high throughput and robustness in accomplishing this task, but the existing pico-injection techniques work in an indiscriminate manner, making it difficult to target particular groups of droplets. Here we report image-activated pico-injection (imgPico) for label-free, on-demand reagent supplementation into droplets. The imgPico detects the droplets of interest by real-time image analysis and makes decisions for the downstream pico-injection operation. We studied the performance of different algorithms for the image analysis and optimized the experimental settings of the imgPico. In the validation experiment, the imgPico successfully injected fluorescent dyes into droplets encapsulating one, two, and three cells, respectively, as expected. We further demonstrated the utility of imgPico by targeting droplets encapsulating single cells in droplet-based single-cell RNA sequencing (scRNA-seq) using exceedingly high cell density, and the results showed that the imgPico effectively reduced the presence of doublets in the scRNA-seq data. With the merits of being label-free and versatile, the imgPico represents a technical advance with potential applications in single-cell analysis.
Collapse
Affiliation(s)
- Zhantao Zhao
- Department of Biomedical Engineering, Medical School, Shenzhen University, Shenzhen, 518060, China; Guangdong Key Laboratory for Biomedical Measurements and Ultrasound Imaging, Department of Biomedical Engineering, Medical School, Shenzhen University, Shenzhen, 518060, China
| | - Heng Zhai
- Department of Biomedical Engineering, Medical School, Shenzhen University, Shenzhen, 518060, China; Guangdong Key Laboratory for Biomedical Measurements and Ultrasound Imaging, Department of Biomedical Engineering, Medical School, Shenzhen University, Shenzhen, 518060, China
| | - Peng Zuo
- ThunderBio Innovation, Shenzhen, 518108, China
| | - Tao Wang
- Department of Biomedical Engineering, Medical School, Shenzhen University, Shenzhen, 518060, China; Guangdong Key Laboratory for Biomedical Measurements and Ultrasound Imaging, Department of Biomedical Engineering, Medical School, Shenzhen University, Shenzhen, 518060, China
| | - Run Xie
- Department of Biomedical Engineering, Medical School, Shenzhen University, Shenzhen, 518060, China; Guangdong Key Laboratory for Biomedical Measurements and Ultrasound Imaging, Department of Biomedical Engineering, Medical School, Shenzhen University, Shenzhen, 518060, China
| | - Mu Tian
- Department of Biomedical Engineering, Medical School, Shenzhen University, Shenzhen, 518060, China; Guangdong Key Laboratory for Biomedical Measurements and Ultrasound Imaging, Department of Biomedical Engineering, Medical School, Shenzhen University, Shenzhen, 518060, China
| | - Ruyuan Song
- ThunderBio Innovation, Shenzhen, 518108, China
| | - Xiaonan Xu
- ThunderBio Innovation, Shenzhen, 518108, China
| | - Zida Li
- Department of Biomedical Engineering, Medical School, Shenzhen University, Shenzhen, 518060, China; Guangdong Key Laboratory for Biomedical Measurements and Ultrasound Imaging, Department of Biomedical Engineering, Medical School, Shenzhen University, Shenzhen, 518060, China.
| |
Collapse
|
3
|
Mao Y, Zhou X, Hu W, Yang W, Cheng Z. Dynamic video recognition for cell-encapsulating microfluidic droplets. Analyst 2024; 149:2147-2160. [PMID: 38441128 DOI: 10.1039/d4an00022f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/26/2024]
Abstract
Droplet microfluidics is a highly sensitive and high-throughput technology extensively utilized in biomedical applications, such as single-cell sequencing and cell screening. However, its performance is highly influenced by the droplet size and single-cell encapsulation rate (following random distribution), thereby creating an urgent need for quality control. Machine learning has the potential to revolutionize droplet microfluidics, but it requires tedious pixel-level annotation for network training. This paper investigates the application software of the weakly supervised cell-counting network (WSCApp) for video recognition of microdroplets. We demonstrated its real-time performance in video processing of microfluidic droplets and further identified the locations of droplets and encapsulated cells. We verified our methods on droplets encapsulating six types of cells/beads, which were collected from various microfluidic structures. Quantitative experimental results showed that our approach can not only accurately distinguish droplet encapsulations (micro-F1 score > 0.94), but also locate each cell without any supervised location information. Furthermore, fine-tuning transfer learning on the pre-trained model also significantly reduced (>80%) annotation. This software provides a user-friendly and assistive annotation platform for the quantitative assessment of cell-encapsulating microfluidic droplets.
Collapse
Affiliation(s)
- Yuanhang Mao
- Department of Automation, Tsinghua University, Beijing, 100084, China.
| | - Xiao Zhou
- Department of Automation, Tsinghua University, Beijing, 100084, China.
| | - Weiguo Hu
- Department of Automation, Tsinghua University, Beijing, 100084, China.
| | - Weiyang Yang
- Department of Automation, Tsinghua University, Beijing, 100084, China.
| | - Zhen Cheng
- Department of Automation, Tsinghua University, Beijing, 100084, China.
| |
Collapse
|
4
|
Tang T, Zhao H, Shen S, Yang L, Lim CT. Enhancing single-cell encapsulation in droplet microfluidics with fine-tunable on-chip sample enrichment. MICROSYSTEMS & NANOENGINEERING 2024; 10:3. [PMID: 38169721 PMCID: PMC10758392 DOI: 10.1038/s41378-023-00631-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/05/2023] [Revised: 10/17/2023] [Accepted: 10/30/2023] [Indexed: 01/05/2024]
Abstract
Single-cell encapsulation in droplet microfluidics is commonly hindered by the tradeoff between cell suspension density and on-chip focusing performance. In this study, we introduce a novel droplet microfluidic chip to overcome this challenge. The chip comprises a double spiral focusing unit, a flow resistance-based sample enrichment module with fine-tunable outlets, and a crossflow droplet generation unit. Utilizing a low-density cell/bead suspension (2 × 106 objects/mL), cells/beads are focused into a near-equidistant linear arrangement within the double spiral microchannel. The excess water phase is diverted while cells/beads remain focused and sequentially encapsulated in individual droplets. Focusing performance was assessed through numerical simulations and experiments at three flow rates (40, 60, 80 μL/min), demonstrating successful focusing at 40 and 80 μL/min for beads and cells, respectively. In addition, both simulation and experimental results revealed that the flow resistance at the sample enrichment module is adjustable by punching different outlets, allowing over 50% of the aqueous phase to be removed. YOLOv8n-based droplet detection algorithms realized the counting of cells/beads in droplets, statistically demonstrating single-cell and bead encapsulation rates of 72.2% and 79.2%, respectively. All the results indicate that this on-chip sample enrichment approach can be further developed and employed as a critical component in single-cell encapsulation in water-in-oil droplets.
Collapse
Affiliation(s)
- Tao Tang
- Department of Biomedical Engineering, National University of Singapore, 117583 Singapore, Singapore
| | - Hao Zhao
- Department of Biomedical Engineering, National University of Singapore, 117583 Singapore, Singapore
- Integrative Sciences and Engineering Programme, NUS Graduate School, National University of Singapore, 119077 Singapore, Singapore
| | - Shaofei Shen
- Shanxi Key Lab for Modernization of TCVM, College of Life Science, Shanxi Agricultural University, Taigu, Shanxi 030801 China
| | - Like Yang
- Department of Biomedical Engineering, National University of Singapore, 117583 Singapore, Singapore
| | - Chwee Teck Lim
- Department of Biomedical Engineering, National University of Singapore, 117583 Singapore, Singapore
- Institute for Health Innovation & Technology, National University of Singapore, 117599 Singapore, Singapore
- Mechanobiology Institute, National University of Singapore, 117411 Singapore, Singapore
- Institute for Digital Molecular Analytics and Science, Nanyang Technological University, 636921 Singapore, Singapore
| |
Collapse
|
5
|
Yang C, Gan X, Zeng Y, Xu Z, Xu L, Hu C, Ma H, Chai B, Hu S, Chai Y. Advanced design and applications of digital microfluidics in biomedical fields: An update of recent progress. Biosens Bioelectron 2023; 242:115723. [PMID: 37832347 DOI: 10.1016/j.bios.2023.115723] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2023] [Revised: 09/11/2023] [Accepted: 09/29/2023] [Indexed: 10/15/2023]
Abstract
Significant breakthroughs have been made in digital microfluidic (DMF)-based technologies over the past decades. DMF technology has attracted great interest in bioassays depending on automatic microscale liquid manipulations and complicated multi-step processing. In this review, the recent advances of DMF platforms in the biomedical field were summarized, focusing on the integrated design and applications of the DMF system. Firstly, the electrowetting-on-dielectric principle, fabrication of DMF chips, and commercialization of the DMF system were elaborated. Then, the updated droplets and magnetic beads manipulation strategies with DMF were explored. DMF-based biomedical applications were comprehensively discussed, including automated sample preparation strategies, immunoassays, molecular diagnosis, blood processing/testing, and microbe analysis. Emerging applications such as enzyme activity assessment and DNA storage were also explored. The performance of each bioassay was compared and discussed, providing insight into the novel design and applications of the DMF technology. Finally, the advantages, challenges, and future trends of DMF systems were systematically summarized, demonstrating new perspectives on the extensive applications of DMF in basic research and commercialization.
Collapse
Affiliation(s)
- Chengbin Yang
- School of Biomedical Engineering, Health Science Center, Shenzhen University, Shenzhen, China.
| | - Xiangyu Gan
- School of Biomedical Engineering, Health Science Center, Shenzhen University, Shenzhen, China.
| | - Yuping Zeng
- School of Biomedical Engineering, Health Science Center, Shenzhen University, Shenzhen, China.
| | - Zhourui Xu
- School of Biomedical Engineering, Health Science Center, Shenzhen University, Shenzhen, China.
| | - Longqian Xu
- CAS Key Laboratory of Bio-Medical Diagnostics, Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, Suzhou, China.
| | - Chenxuan Hu
- CAS Key Laboratory of Bio-Medical Diagnostics, Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, Suzhou, China.
| | - Hanbin Ma
- CAS Key Laboratory of Bio-Medical Diagnostics, Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, Suzhou, China; Guangdong ACXEL Micro & Nano Tech Co., Ltd, Foshan, China.
| | - Bao Chai
- Department of Dermatology, Huazhong University of Science and Technology Union Shenzhen Hospital, Shenzhen, China; Department of Dermatology, The 6th Affiliated Hospital of Shenzhen University Health Science Center, Shenzhen, China.
| | - Siyi Hu
- CAS Key Laboratory of Bio-Medical Diagnostics, Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, Suzhou, China.
| | - Yujuan Chai
- School of Biomedical Engineering, Health Science Center, Shenzhen University, Shenzhen, China.
| |
Collapse
|
6
|
Zeng Z, Tian J, Ren Z, Yang Y, Gong Q, Sun R, Zhang X, Liu W, Chen C. Digital droplet immunoassay based on a microfluidic chip with magnetic beads for the detection of prostate-specific antigen. J Sep Sci 2023; 46:e2300471. [PMID: 37905470 DOI: 10.1002/jssc.202300471] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2023] [Revised: 10/08/2023] [Accepted: 10/13/2023] [Indexed: 11/02/2023]
Abstract
Sensitive biomarker detection techniques are beneficial for both disease diagnosis and postoperative examinations. In this study, we report an integrated microfluidic chip designed for the immunodetection of prostate-specific antigens (PSAs). The microfluidic chip is based on the three-dimensional structure of quartz capillaries. The outlet channel extends to 1.8 cm, effectively facilitating the generation of uniform droplets ranging in size from 3 to 50 μm. Furthermore, we successfully immobilized the captured antibodies onto the surface of magnetic beads using an activator, and we constructed an immunosandwich complex by employing biotinylated antibodies. A key feature of this microfluidic chip is its integration of microfluidic droplet technology advantages, such as high-throughput parallelism, enzymatic signal amplification, and small droplet size. This integration results in an exceptionally sensitive PSA detection capability, with the detection limit reduced to 7.00 ± 0.62 pg/mL.
Collapse
Affiliation(s)
- Zhaokui Zeng
- Department of Pharmacy, Xiangya School of Pharmaceutical Sciences, Central South University, Changsha, China
| | - Jingjing Tian
- Department of Pharmacy, Xiangya School of Pharmaceutical Sciences, Central South University, Changsha, China
| | - Zixuan Ren
- Department of Pharmacy, Xiangya School of Pharmaceutical Sciences, Central South University, Changsha, China
| | - Ying Yang
- Department of Pharmacy, Xiangya School of Pharmaceutical Sciences, Central South University, Changsha, China
| | - Qian Gong
- Department of Pharmacy, Hunan Cancer Hospital/The Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University, Changsha, China
| | - Ruowei Sun
- Hunan Zaochen Nanorobot Co.Ltd, Liuyang, China
| | - Xun Zhang
- Hunan Zaochen Nanorobot Co.Ltd, Liuyang, China
| | - Wenfang Liu
- Department of Pharmacy, Xiangya School of Pharmaceutical Sciences, Central South University, Changsha, China
| | - Chuanpin Chen
- Department of Pharmacy, Xiangya School of Pharmaceutical Sciences, Central South University, Changsha, China
| |
Collapse
|
7
|
Yang G, Gao C, Chen D, Wang J, Huo X, Chen J. Multiplex fluorescence detection of single-cell droplet microfluidics and its application in quantifying protein expression levels. BIOMICROFLUIDICS 2023; 17:064106. [PMID: 38162228 PMCID: PMC10754627 DOI: 10.1063/5.0179121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Accepted: 11/29/2023] [Indexed: 01/03/2024]
Abstract
This study presented a platform of multiplex fluorescence detection of single-cell droplet microfluidics with demonstrative applications in quantifying protein expression levels. The platform of multiplex fluorescence detection mainly included optical paths adopted from conventional microscopy enabling the generation of three optical spots from three laser sources for multiple fluorescence excitation and capture of multiple fluorescence signals by four photomultiplier tubes. As to platform characterization, microscopic images of three optical spots were obtained where clear Gaussian distributions of intensities without skewness confirmed the functionality of the scanning lens, while the controllable distances among three optical spots validated the functionality of fiber collimators and the reflector lens. As to demonstration, this platform was used to quantify single-cell protein expression within droplets where four-type protein expression of α-tubulin, Ras, c-Myc, and β-tubulin of CAL 27 (Ncell = 1921) vs WSU-HN6 (Ncell = 1881) were quantitatively estimated, which were (2.85 ± 0.72) × 105 vs (4.83 ± 1.58) × 105, (3.69 ± 1.41) × 104 vs (5.07 ± 2.13) × 104, (5.90 ± 1.45) × 104 vs (9.57 ± 2.85) × 104, and (3.84 ± 1.28) × 105 vs (3.30 ± 1.10) × 105, respectively. Neural pattern recognition was utilized for the classification of cell types, achieving successful rates of 69.0% (α-tubulin), 75.4% (Ras), 89.1% (c-Myc), 65.8% (β-tubulin), and 99.1% in combination, validating the capability of this platform of multiplex fluorescence detection to quantify various types of single-cell proteins, which could provide comprehensive evaluations on cell status.
Collapse
Affiliation(s)
| | | | | | - Junbo Wang
- Authors to whom correspondence should be addressed:; ; and
| | - Xiaoye Huo
- Authors to whom correspondence should be addressed:; ; and
| | - Jian Chen
- Authors to whom correspondence should be addressed:; ; and
| |
Collapse
|
8
|
Hou Y, Yao H, Lin JM. Recent advancements in single-cell metabolic analysis for pharmacological research. J Pharm Anal 2023; 13:1102-1116. [PMID: 38024859 PMCID: PMC10658044 DOI: 10.1016/j.jpha.2023.08.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Revised: 08/12/2023] [Accepted: 08/18/2023] [Indexed: 12/01/2023] Open
Abstract
Cellular heterogeneity is crucial for understanding tissue biology and disease pathophysiology. Pharmacological research is being advanced by single-cell metabolic analysis, which offers a technique to identify variations in RNA, proteins, metabolites, and drug molecules in cells. In this review, the recent advancement of single-cell metabolic analysis techniques and their applications in drug metabolism and drug response are summarized. High-precision and controlled single-cell isolation and manipulation are provided by microfluidics-based methods, such as droplet microfluidics, microchamber, open microfluidic probe, and digital microfluidics. They are used in tandem with variety of detection techniques, including optical imaging, Raman spectroscopy, electrochemical detection, RNA sequencing, and mass spectrometry, to evaluate single-cell metabolic changes in response to drug administration. The advantages and disadvantages of different techniques are discussed along with the challenges and future directions for single-cell analysis. These techniques are employed in pharmaceutical analysis for studying drug response and resistance pathway, therapeutic targets discovery, and in vitro disease model evaluation.
Collapse
Affiliation(s)
- Ying Hou
- Beijing Key Laboratory of Microanalytical Methods and Instrumentation, Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing, 100084, China
| | - Hongren Yao
- Beijing Key Laboratory of Microanalytical Methods and Instrumentation, Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing, 100084, China
| | - Jin-Ming Lin
- Beijing Key Laboratory of Microanalytical Methods and Instrumentation, Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing, 100084, China
| |
Collapse
|
9
|
Zhang Y, Lin Y, Hong X, Di C, Xin Y, Wang X, Qi S, Liu BF, Zhang Z, Du W. Demand-driven active droplet generation and sorting based on positive pressure-controlled fluid wall. Anal Bioanal Chem 2023; 415:5311-5322. [PMID: 37392212 DOI: 10.1007/s00216-023-04806-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Revised: 06/08/2023] [Accepted: 06/12/2023] [Indexed: 07/03/2023]
Abstract
Droplet microfluidics is a rapidly advancing area of microfluidic technology, which offers numerous advantages for cell analysis, such as isolation and accumulation of signals, by confining cells within droplets. However, controlling cell numbers in droplets is challenging due to the uncertainty of random encapsulation which result in many empty droplets. Therefore, more precise control techniques are needed to achieve efficient encapsulation of cells within droplets. Here, an innovative microfluidic droplet manipulation platform had been developed, which employed positive pressure as a stable and controllable driving force for manipulating fluid within chips. The air cylinder, electro-pneumatics proportional valve, and the microfluidic chip were connected through a capillary, which enabled the formation of a fluid wall by creating a difference in hydrodynamic resistance between two fluid streams at the channel junction. Lowering the pressure of the driving oil phase eliminates hydrodynamic resistance and breaks the fluid wall. Regulating the duration of the fluid wall breakage controls the volume of the introduced fluid. Several important droplet microfluidic manipulations were demonstrated on this microfluidic platform, such as sorting of cells/droplets, sorting of droplets co-encapsulated cells and hydrogels, and active generation of droplets encapsulated with cells in a responsive manner. The simple, on-demand microfluidic platform was featured with high stability, good controllability, and compatibility with other droplet microfluidic technologies.
Collapse
Affiliation(s)
- Yiwei Zhang
- The Key Laboratory for Biomedical Photonics of MOE at Wuhan National Laboratory for Optoelectronics - Hubei Bioinformatics & Molecular Imaging Key Laboratory, Systems Biology Theme, Department of Biomedical Engineering, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, 430074, China
| | - Yiwei Lin
- The Key Laboratory for Biomedical Photonics of MOE at Wuhan National Laboratory for Optoelectronics - Hubei Bioinformatics & Molecular Imaging Key Laboratory, Systems Biology Theme, Department of Biomedical Engineering, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, 430074, China
| | - Xianzhe Hong
- The Key Laboratory for Biomedical Photonics of MOE at Wuhan National Laboratory for Optoelectronics - Hubei Bioinformatics & Molecular Imaging Key Laboratory, Systems Biology Theme, Department of Biomedical Engineering, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, 430074, China
| | - Chao Di
- The Key Laboratory for Biomedical Photonics of MOE at Wuhan National Laboratory for Optoelectronics - Hubei Bioinformatics & Molecular Imaging Key Laboratory, Systems Biology Theme, Department of Biomedical Engineering, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, 430074, China
| | - Yuelai Xin
- The Key Laboratory for Biomedical Photonics of MOE at Wuhan National Laboratory for Optoelectronics - Hubei Bioinformatics & Molecular Imaging Key Laboratory, Systems Biology Theme, Department of Biomedical Engineering, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, 430074, China
| | - Xinru Wang
- The Key Laboratory for Biomedical Photonics of MOE at Wuhan National Laboratory for Optoelectronics - Hubei Bioinformatics & Molecular Imaging Key Laboratory, Systems Biology Theme, Department of Biomedical Engineering, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, 430074, China
| | - Shuhong Qi
- The Key Laboratory for Biomedical Photonics of MOE at Wuhan National Laboratory for Optoelectronics - Hubei Bioinformatics & Molecular Imaging Key Laboratory, Systems Biology Theme, Department of Biomedical Engineering, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, 430074, China
| | - Bi-Feng Liu
- The Key Laboratory for Biomedical Photonics of MOE at Wuhan National Laboratory for Optoelectronics - Hubei Bioinformatics & Molecular Imaging Key Laboratory, Systems Biology Theme, Department of Biomedical Engineering, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, 430074, China
| | - Zhihong Zhang
- The Key Laboratory for Biomedical Photonics of MOE at Wuhan National Laboratory for Optoelectronics - Hubei Bioinformatics & Molecular Imaging Key Laboratory, Systems Biology Theme, Department of Biomedical Engineering, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, 430074, China
| | - Wei Du
- The Key Laboratory for Biomedical Photonics of MOE at Wuhan National Laboratory for Optoelectronics - Hubei Bioinformatics & Molecular Imaging Key Laboratory, Systems Biology Theme, Department of Biomedical Engineering, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, 430074, China.
| |
Collapse
|
10
|
Zhou X, Mao Y, Gu M, Cheng Z. WSCNet: Biomedical Image Recognition for Cell Encapsulated Microfluidic Droplets. BIOSENSORS 2023; 13:821. [PMID: 37622907 PMCID: PMC10452702 DOI: 10.3390/bios13080821] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Revised: 08/08/2023] [Accepted: 08/12/2023] [Indexed: 08/26/2023]
Abstract
Microfluidic droplets accommodating a single cell as independent microreactors are frequently demanded for single-cell analysis of phenotype and genotype. However, challenges exist in identifying and reducing the covalence probability (following Poisson's distribution) of more than two cells encapsulated in one droplet. It is of great significance to monitor and control the quantity of encapsulated content inside each droplet. We demonstrated a microfluidic system embedded with a weakly supervised cell counting network (WSCNet) to generate microfluidic droplets, evaluate their quality, and further recognize the locations of encapsulated cells. Here, we systematically verified our approach using encapsulated droplets from three different microfluidic structures. Quantitative experimental results showed that our approach can not only distinguish droplet encapsulations (F1 score > 0.88) but also locate each cell without any supervised location information (accuracy > 89%). The probability of a "single cell in one droplet" encapsulation is systematically verified under different parameters, which shows good agreement with the distribution of the passive method (Residual Sum of Squares, RSS < 0.5). This study offers a comprehensive platform for the quantitative assessment of encapsulated microfluidic droplets.
Collapse
Affiliation(s)
| | | | | | - Zhen Cheng
- Department of Automation, Tsinghua University, Beijing 100084, China
| |
Collapse
|
11
|
Zheng F, Wang J, Wang D, Yang Q. Clinical Application of Small Extracellular Vesicles in Gynecologic Malignancy Treatments. Cancers (Basel) 2023; 15:cancers15071984. [PMID: 37046644 PMCID: PMC10093031 DOI: 10.3390/cancers15071984] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2023] [Revised: 03/22/2023] [Accepted: 03/24/2023] [Indexed: 03/29/2023] Open
Abstract
Small extracellular vesicles (sEVs) are the key mediators of intercellular communication. They have the potential for clinical use as diagnostic or therapeutic biomarkers and have been explored as vectors for drug delivery. Identification of reliable and noninvasive biomarkers, such as sEVs, is important for early diagnosis and precise treatment of gynecologic diseases to improve patient prognosis. Previous reviews have summarized routine sEVs isolation and identification methods; however, novel and unconventional methods have not been comprehensively described. This review summarizes a convenient method of isolating sEVs from body fluids and liquid biopsy-related sEV markers for early, minimally invasive diagnosis of gynecologic diseases. In addition, the characteristics of sEVs as drug carriers and in precision treatment and drug resistance are introduced, providing a strong foundation for identifying novel and potential therapeutic targets for sEV therapy. We propose potential directions for further research on the applications of sEVs in the diagnosis and treatment of gynecologic diseases.
Collapse
|
12
|
Abstract
This paper reviews methods for detecting proteins based on molecular digitization, i.e., the isolation and detection of single protein molecules or singulated ensembles of protein molecules. The single molecule resolution of these methods has resulted in significant improvements in the sensitivity of immunoassays beyond what was possible using traditional "analog" methods: the sensitivity of some digital immunoassays approach those of methods for measuring nucleic acids, such as the polymerase chain reaction (PCR). The greater sensitivity of digital protein detection has resulted in immuno-diagnostics with high potential societal impact, e.g., the early diagnosis and therapeutic intervention of Alzheimer's Disease. In this review, we will first provide the motivation for developing digital protein detection methods given the limitations in the sensitivity of analog methods. We will describe the paradigm shift catalyzed by single molecule detection, and will describe in detail one digital approach - which we call digital bead assays (DBA) - based on the capture and labeling of proteins on beads, identifying "on" and "off" beads, and quantification using Poisson statistics. DBA based on the single molecule array (Simoa) technology have sensitivities down to attomolar concentrations, equating to ∼10 proteins in a 200 μL sample. We will describe the concept behind DBA, the different single molecule labels used, the ways of analyzing beads (imaging of arrays and flow), the binding reagents and substrates used, and integration of these technologies into fully automated and miniaturized systems. We provide an overview of emerging approaches to digital protein detection, including those based on digital detection of nucleic acids labels, single nanoparticle detection, measurements using nanopores, and methods that exploit the kinetics of single molecule binding. We outline the initial impact of digital protein detection on clinical measurements, highlighting the importance of customized assay development and translational clinical research. We highlight the use of DBA in the measurement of neurological protein biomarkers in blood, and how these higher sensitivity methods are changing the diagnosis and treatment of neurological diseases. We conclude by summarizing the status of digital protein detection and suggest how the lab-on-a-chip community might drive future innovations in this field.
Collapse
Affiliation(s)
- David C Duffy
- Quanterix Corporation, 900 Middlesex Turnpike, Billerica, MA 01821, USA.
| |
Collapse
|
13
|
Jeyasountharan A, Giudice FD. Viscoelastic Particle Encapsulation Using a Hyaluronic Acid Solution in a T-Junction Microfluidic Device. MICROMACHINES 2023; 14:563. [PMID: 36984969 PMCID: PMC10053877 DOI: 10.3390/mi14030563] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Revised: 02/24/2023] [Accepted: 02/25/2023] [Indexed: 06/18/2023]
Abstract
The encapsulation of particles and cells in droplets is highly relevant in biomedical engineering as well as in material science. So far, however, the majority of the studies in this area have focused on the encapsulation of particles or cells suspended in Newtonian liquids. We here studied the particle encapsulation phenomenon in a T-junction microfluidic device, using a non-Newtonian viscoelastic hyaluronic acid solution in phosphate buffer saline as suspending liquid for the particles. We first studied the non-Newtonian droplet formation mechanism, finding that the data for the normalised droplet length scaled as the Newtonian ones. We then performed viscoelastic encapsulation experiments, where we exploited the fact that particles self-assembled in equally-spaced structures before approaching the encapsulation area, to then identify some experimental conditions for which the single encapsulation efficiency was larger than the stochastic limit predicted by the Poisson statistics.
Collapse
|
14
|
Zhang T, Gao M, Chen X, Gao C, Feng S, Chen D, Wang J, Zhao X, Chen J. Demands and technical developments of clinical flow cytometry with emphasis in quantitative, spectral, and imaging capabilities. NANOTECHNOLOGY AND PRECISION ENGINEERING 2022. [DOI: 10.1063/10.0015301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
As the gold-standard method for single-cell analysis, flow cytometry enables high-throughput and multiple-parameter characterization of individual biological cells. This review highlights the demands for clinical flow cytometry in laboratory hematology (e.g., diagnoses of minimal residual disease and various types of leukemia), summarizes state-of-the-art clinical flow cytometers (e.g., FACSLyricTM by Becton Dickinson, DxFLEX by Beckman Coulter), then considers innovative technical improvements in flow cytometry (including quantitative, spectral, and imaging approaches) to address the limitations of clinical flow cytometry in hematology diagnosis. Finally, driven by these clinical demands, future developments in clinical flow cytometry are suggested.
Collapse
Affiliation(s)
- Ting Zhang
- State Key Laboratory of Transducer Technology, Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing 100190, People’s Republic of China
- School of Future Technology, University of Chinese Academy of Sciences, Beijing 100049, People’s Republic of China
| | - Mengge Gao
- Peking University People’s Hospital, Peking University Institute of Hematology, National Clinical Research Center for Hematologic Disease, Beijing Key Laboratory of Hematopoietic Stem Cell Transplantation, Beijing 100044, People’s Republic of China
| | - Xiao Chen
- State Key Laboratory of Transducer Technology, Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing 100190, People’s Republic of China
- School of Future Technology, University of Chinese Academy of Sciences, Beijing 100049, People’s Republic of China
| | - Chiyuan Gao
- State Key Laboratory of Transducer Technology, Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing 100190, People’s Republic of China
- School of Future Technology, University of Chinese Academy of Sciences, Beijing 100049, People’s Republic of China
| | - Shilun Feng
- State Key Laboratory of Transducer Technology, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, Shanghai 200050, People’s Republic of China
| | - Deyong Chen
- State Key Laboratory of Transducer Technology, Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing 100190, People’s Republic of China
- School of Future Technology, University of Chinese Academy of Sciences, Beijing 100049, People’s Republic of China
- School of Electronic, Electrical and Communication Engineering, University of Chinese Academy of Sciences, Beijing 100049, People’s Republic of China
| | - Junbo Wang
- State Key Laboratory of Transducer Technology, Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing 100190, People’s Republic of China
- School of Future Technology, University of Chinese Academy of Sciences, Beijing 100049, People’s Republic of China
- School of Electronic, Electrical and Communication Engineering, University of Chinese Academy of Sciences, Beijing 100049, People’s Republic of China
| | - Xiaosu Zhao
- Peking University People’s Hospital, Peking University Institute of Hematology, National Clinical Research Center for Hematologic Disease, Beijing Key Laboratory of Hematopoietic Stem Cell Transplantation, Beijing 100044, People’s Republic of China
| | - Jian Chen
- State Key Laboratory of Transducer Technology, Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing 100190, People’s Republic of China
- School of Future Technology, University of Chinese Academy of Sciences, Beijing 100049, People’s Republic of China
- School of Electronic, Electrical and Communication Engineering, University of Chinese Academy of Sciences, Beijing 100049, People’s Republic of China
| |
Collapse
|
15
|
Yang G, Yang H, Zhang T, Gao C, Chen D, Wang J, Chen J. Quantitative flow cytometry leveraging
droplet‐based
constriction microchannels with high reliability and high sensitivity. Cytometry A 2022; 103:429-438. [PMID: 36420790 DOI: 10.1002/cyto.a.24705] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2022] [Revised: 10/08/2022] [Accepted: 11/08/2022] [Indexed: 11/24/2022]
Abstract
This study presented a quantitative flow cytometry leveraging droplet-based constriction microchannels with high reliability and high sensitivity. Droplets encapsulating single cells and even distribution of fluorescein labeled antibodies removed from targeted cells deformed through the constriction microchannel where the excited fluorescent signals were sampled and interpreted into numbers of proteins based on volume equivalence in measurement of droplets and calibration of fluorescence. To improve the detection reliability, a comprehensive analysis and comparison of multiple stripping agents such as proteinase K, guanidine hydrochloride, and urea was conducted. To improve the detection sensitivity, light modulation was used to address electrical noises and quartz microchannels were fabricated to address optical noises. As a demonstration, based on this quantitative flow cytometry of droplet microfluidics, (1) mutant p53 expressions of single cells were quantified as 1.95 ± 0.60 × 105 (ncell = 2918 of A431) and 1.30 ± 0.70 × 105 (ncell = 3954 of T47D); (2) single-cell expressions of Ras, c-Myc, and β-tubulin were quantified as 1.90 ± 0.59 × 105 , 4.39 ± 1.44 × 105 , and 2.97 ± 0.81 × 105 (ncell = 3298 of CAL 27), 1.83 ± 0.58 × 105 , 2.08 ± 0.13 × 106 , and 1.96 ± 0.74 × 105 (ncell = 5459 of WSU-HN6). As a microfluidic tool capable of quantitatively estimating single-cell protein expressions, this methodology may provide a new quantitative perspective for the field of flow cytometry.
Collapse
Affiliation(s)
- Guang Yang
- State Key Laboratory of Transducer Technology Aerospace Information Research Institute of Chinese Academy of Sciences Beijing China
- School of Electronic, Electrical and Communication Engineering University of Chinese Academy of Sciences Beijing China
| | - Hongyu Yang
- State Key Laboratory of Transducer Technology Aerospace Information Research Institute of Chinese Academy of Sciences Beijing China
- School of Future Technology University of Chinese Academy of Sciences Beijing China
| | - Ting Zhang
- State Key Laboratory of Transducer Technology Aerospace Information Research Institute of Chinese Academy of Sciences Beijing China
- School of Future Technology University of Chinese Academy of Sciences Beijing China
| | - Chiyuan Gao
- State Key Laboratory of Transducer Technology Aerospace Information Research Institute of Chinese Academy of Sciences Beijing China
- School of Future Technology University of Chinese Academy of Sciences Beijing China
| | - Deyong Chen
- State Key Laboratory of Transducer Technology Aerospace Information Research Institute of Chinese Academy of Sciences Beijing China
- School of Electronic, Electrical and Communication Engineering University of Chinese Academy of Sciences Beijing China
- School of Future Technology University of Chinese Academy of Sciences Beijing China
| | - Junbo Wang
- State Key Laboratory of Transducer Technology Aerospace Information Research Institute of Chinese Academy of Sciences Beijing China
- School of Electronic, Electrical and Communication Engineering University of Chinese Academy of Sciences Beijing China
- School of Future Technology University of Chinese Academy of Sciences Beijing China
| | - Jian Chen
- State Key Laboratory of Transducer Technology Aerospace Information Research Institute of Chinese Academy of Sciences Beijing China
- School of Electronic, Electrical and Communication Engineering University of Chinese Academy of Sciences Beijing China
- School of Future Technology University of Chinese Academy of Sciences Beijing China
| |
Collapse
|
16
|
Selective single-bacteria extraction based on capture and release of microemulsion droplets. Sci Rep 2022; 12:15461. [PMID: 36104374 PMCID: PMC9474873 DOI: 10.1038/s41598-022-19844-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2022] [Accepted: 09/05/2022] [Indexed: 12/02/2022] Open
Abstract
Human host-associated microbial communities in body sites can reflect health status based on the population distribution and specific microbial properties in the heterogeneous community. Bacteria identification at the single-cell level provides a reliable biomarker and pathological information for clinical diagnosis. Nevertheless, biosamples obtained from some body sites cannot offer sufficient sample volume and number of target cells as required by most of the existing single-cell isolation methods such as flow cytometry. Herein we report a novel integrated microfluidic system, which consists of a microemulsion module for single-bacteria encapsulation and a sequential microdroplet capture and release module for selectively extracting only the single-bacteria encapsulated in microdroplets. We optimize the system for a success rate of the single-cell extraction to be > 38%. We further verify applicability of the system with prepared cell mixtures (Methylorubrum extorquens AM1 and Methylomicrobium album BG8) and biosamples collected from human skin, to quantify the population distribution of multiple key species in a heterogeneous microbial community. Results indicate perfect viability of the single-cell extracts and compatibility with downstream analyses such as PCR. Together, this research demonstrates that the reported single-bacteria extraction system can be applied in microbiome and pathology research and clinical diagnosis as a clinical or point-of-care device.
Collapse
|
17
|
Curtin K, Fike BJ, Binkley B, Godary T, Li P. Recent Advances in Digital Biosensing Technology. BIOSENSORS 2022; 12:bios12090673. [PMID: 36140058 PMCID: PMC9496261 DOI: 10.3390/bios12090673] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/30/2022] [Revised: 08/16/2022] [Accepted: 08/17/2022] [Indexed: 11/27/2022]
Abstract
Digital biosensing assays demonstrate remarkable advantages over conventional biosensing systems because of their ability to achieve single-molecule detection and absolute quantification. Unlike traditional low-abundance biomarking screening, digital-based biosensing systems reduce sample volumes significantly to the fL-nL level, which vastly reduces overall reagent consumption, improves reaction time and throughput, and enables high sensitivity and single target detection. This review presents the current technology for compartmentalizing reactions and their applications in detecting proteins and nucleic acids. We also analyze existing challenges and future opportunities associated with digital biosensing and research opportunities for developing integrated digital biosensing systems.
Collapse
Affiliation(s)
- Kathrine Curtin
- Department of Mechanical and Aerospace Engineering, West Virginia University, Morgantown, WV 26506, USA
| | - Bethany J. Fike
- C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, WV 26506, USA
| | - Brandi Binkley
- C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, WV 26506, USA
| | - Toktam Godary
- C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, WV 26506, USA
| | - Peng Li
- C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, WV 26506, USA
- Correspondence:
| |
Collapse
|