Microsystems & Nanoengineering最新文献

{"title":"A low-voltage-driven MEMS ultrasonic phased-array transducer for fast 3D volumetric imaging","authors":"Yun Zhang, Tong Jin, Yining Deng, Zijie Zhao, Rui Wang, Qiong He, Jianwen Luo, Jiawei Li, Kang Du, Tao Wu, Chenfang Yan, Hao Zhang, Xinchao Lu, Chengjun Huang, Hang Gao","doi":"10.1038/s41378-024-00755-9","DOIUrl":"https://doi.org/10.1038/s41378-024-00755-9","url":null,"abstract":"<p>Wearable ultrasound imaging technology has become an emerging modality for the continuous monitoring of deep-tissue physiology, providing crucial health and disease information. Fast volumetric imaging that can provide a full spatiotemporal view of intrinsic 3D targets is desirable for interpreting internal organ dynamics. However, existing 1D ultrasound transducer arrays provide 2D images, making it challenging to overcome the trade-off between the temporal resolution and volumetric coverage. In addition, the high driving voltage limits their implementation in wearable settings. With the use of microelectromechanical system (MEMS) technology, we report an ultrasonic phased-array transducer, i.e., a 2D piezoelectric micromachined ultrasound transducer (pMUT) array, which is driven by a low voltage and is chip-compatible for fast 3D volumetric imaging. By grouping multiple pMUT cells into one single drive channel/element, we propose an innovative cell–element–array design and operation of a pMUT array that can be used to quantitatively characterize the key coupling effects between each pMUT cell, allowing 3D imaging with 5-V actuation. The pMUT array demonstrates fast volumetric imaging covering a range of 40 mm × 40 mm × 70 mm in wire phantom and vascular phantom experiments, achieving a high temporal frame rate of 11 kHz. The proposed solution offers a full volumetric view of deep-tissue disorders in a fast manner, paving the way for long-term wearable imaging technology for various organs in deep tissues.</p><figure></figure>","PeriodicalId":18560,"journal":{"name":"Microsystems & Nanoengineering","volume":null,"pages":null},"PeriodicalIF":7.9,"publicationDate":"2024-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142193428","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Designing magnetic microcapsules for cultivation and differentiation of stem cell spheroids","authors":"Kihak Gwon, Ether Dharmesh, Kianna M. Nguyen, Anna Marie R. Schornack, Jose M. de Hoyos-Vega, Hakan Ceylan, Gulnaz Stybayeva, Quinn P. Peterson, Alexander Revzin","doi":"10.1038/s41378-024-00747-9","DOIUrl":"https://doi.org/10.1038/s41378-024-00747-9","url":null,"abstract":"<p>Human pluripotent stem cells (hPSCs) represent an excellent cell source for regenerative medicine and tissue engineering applications. However, there remains a need for robust and scalable differentiation of stem cells into functional adult tissues. In this paper, we sought to address this challenge by developing magnetic microcapsules carrying hPSC spheroids. A co-axial flow-focusing microfluidic device was employed to encapsulate stem cells in core-shell microcapsules that also contained iron oxide magnetic nanoparticles (MNPs). These microcapsules exhibited excellent response to an external magnetic field and could be held at a specific location. As a demonstration of utility, magnetic microcapsules were used for differentiating hPSC spheroids as suspension cultures in a stirred bioreactor. Compared to standard suspension cultures, magnetic microcapsules allowed for more efficient media change and produced improved differentiation outcomes. In the future, magnetic microcapsules may enable better and more scalable differentiation of hPSCs into adult cell types and may offer benefits for cell transplantation.</p><figure></figure>","PeriodicalId":18560,"journal":{"name":"Microsystems & Nanoengineering","volume":null,"pages":null},"PeriodicalIF":7.9,"publicationDate":"2024-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142193413","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Microdissection tools to generate organoids for modeling the tumor immune microenvironment","authors":"Seth C. Cordts, Kanako Yuki, Maria F. Henao Echeverri, Balasubramanian Narasimhan, Calvin J. Kuo, Sindy K. Y. Tang","doi":"10.1038/s41378-024-00756-8","DOIUrl":"https://doi.org/10.1038/s41378-024-00756-8","url":null,"abstract":"<p>Patient-derived tumor organoids have emerged as promising models for predicting personalized drug responses in cancer therapy, but they typically lack immune components. Preserving the in vivo association between tumor cells and endogenous immune cells is critical for accurate testing of cancer immunotherapies. Mechanical dissection of tumor specimens into tumor fragments, as opposed to enzymatic digestion into single cells, is essential for maintaining these native tumor-immune cell spatial relationships. However, conventional mechanical dissection relying on manual mincing is time-consuming and irreproducible. This study describes two microdissection devices, the µDicer and µGrater, to facilitate the generation of intact tumor fragments from mouse B16 melanoma, a common model of human melanoma. The µDicer- and µGrater-cut tumor fragments were used to generate air‒liquid interface (ALI) organoids that copreserve tumor cells with infiltrating immune subsets without artificial reconstitution. The µDicer, consisting of a hexagonal array of silicon microblades, was employed to investigate the effect of organoid size. The viability of ALI organoid immune cells appeared insensitive to organoid sizes exceeding ~400 µm but diminished in organoids ~200 µm in size. The µGrater, consisting of an array of submillimeter holes in stainless steel, was employed to accelerate dissection. For the samples studied, the µGrater was 4.5 times faster than manual mincing. Compared with those generated by manual mincing, ALI organoids generated by the µGrater demonstrated similar viability, immune cell composition, and responses to anti-PD-1 immunotherapy. With further optimization, the µGrater holds potential for integration into clinical workflows to support the advancement of personalized cancer immunotherapy.</p><figure></figure>","PeriodicalId":18560,"journal":{"name":"Microsystems & Nanoengineering","volume":null,"pages":null},"PeriodicalIF":7.9,"publicationDate":"2024-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142193416","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sustainability inspired fabrication of next generation neurostimulation and cardiac rhythm management electrodes via reactive hierarchical surface restructuring","authors":"Shahram Amini, Hongbin Choi, Wesley Seche, Alexander Blagojevic, Nicholas May, Benjamin M. Lefler, Skyler L. Davis, Sahar Elyahoodayan, Pouya Tavousi, Steven J. May, Gregory A. Caputo, Terry C. Lowe, Jeffrey Hettinger, Sina Shahbazmohamadi","doi":"10.1038/s41378-024-00754-w","DOIUrl":"https://doi.org/10.1038/s41378-024-00754-w","url":null,"abstract":"<p>Over the last two decades, platinum group metals (PGMs) and their alloys have dominated as the materials of choice for electrodes in long-term implantable neurostimulation and cardiac rhythm management devices due to their superior conductivity, mechanical and chemical stability, biocompatibility, corrosion resistance, radiopacity, and electrochemical performance. Despite these benefits, PGM manufacturing processes are extremely costly, complex, and challenging with potential health hazards. Additionally, the volatility in PGM prices and their high supply risk, combined with their scarce concentration of approximately 0.01 ppm in the earth’s upper crust and limited mining geographical areas, underscores their classification as critical raw materials, thus, their effective recovery or substitution worldwide is of paramount importance. Since postmortem recovery from deceased patients and/or refining of PGMs that are used in the manufacturing of the electrodes and microelectrode arrays is extremely rare, challenging, and highly costly, therefore, substitution of PGM-based electrodes with other biocompatible materials that can yield electrochemical performance values equal or greater than PGMs is the only viable and sustainable solution to reduce and ultimately substitute the use of PGMs in long-term implantable neurostimulation and cardiac rhythm management devices. In this article, we demonstrate for the first time how the novel technique of “reactive hierarchical surface restructuring” can be utilized on titanium—that is widely used in many non-stimulation medical device and implant applications—to manufacture biocompatible, low-cost, sustainable, and high-performing neurostimulation and cardiac rhythm management electrodes. We have shown how the surface of titanium electrodes with extremely poor electrochemical performance undergoes compositional and topographical transformations that result in electrodes with outstanding electrochemical performance.</p>","PeriodicalId":18560,"journal":{"name":"Microsystems & Nanoengineering","volume":null,"pages":null},"PeriodicalIF":7.9,"publicationDate":"2024-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142193414","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Noncontact excitation of multi-GHz lithium niobate electromechanical resonators.","authors":"Danqing Wang, Jiacheng Xie, Yu Guo, Mohan Shen, Hong X Tang","doi":"10.1038/s41378-024-00771-9","DOIUrl":"10.1038/s41378-024-00771-9","url":null,"abstract":"<p><p>The demand for high-performance electromechanical resonators is ever-growing across diverse applications, ranging from sensing and time-keeping to advanced communication devices. Among the electromechanical materials being explored, thin-film lithium niobate stands out due to its strong piezoelectric properties and low acoustic loss. However, in nearly all existing lithium niobate electromechanical devices, the configuration is such that the electrodes are in direct contact with the mechanical resonator. This configuration introduces an undesirable mass-loading effect, producing spurious modes and additional damping. Here, we present an electromechanical platform that mitigates this challenge by leveraging a flip-chip bonding technique to separate the electrodes from the mechanical resonator. By offloading the electrodes from the resonator, our approach yields a substantial increase in the quality factor of these resonators, paving the way for enhanced performance and reliability for their device applications.</p>","PeriodicalId":18560,"journal":{"name":"Microsystems & Nanoengineering","volume":null,"pages":null},"PeriodicalIF":7.3,"publicationDate":"2024-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11377770/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142140529","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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":"Zero-power infrared switch with two-phase microfluidic flow and a 2D material thermal isolation layer.","authors":"Zekun Zhang, Peng Li, Yixuan Zou","doi":"10.1038/s41378-024-00761-x","DOIUrl":"10.1038/s41378-024-00761-x","url":null,"abstract":"<p><p>Wireless sensor nodes (WSNs) play an important role in many fields, including environmental monitoring. However, unattended WSNs face challenges in consuming power continuously even in the absence of useful information, which makes energy supply the bottleneck of WSNs. Here, we realized zero-power infrared switches, which consist of a metasurface and two-phase microfluidic flow. The metasurface can recognize the infrared signal from the target and convert it into heat, which triggers the two-phase microfluidic flow switch. As the target is not present, the switch is turned off. The graphene/MoS₂/graphene 2D material heterostructure (thickness <2 nm) demonstrates an exceptionally high thermal resistance of 4.2 K/W due to strong phonon scattering and reduces the heat flow from the metasurface to the supporting substrate, significantly increasing the device sensitivity (the displacement of the two-phase microfluidic flow increases from ~1500 to ~3000 µm). The infrared switch with a pair of symmetric two-phase microfluidic flows can avoid spurious triggering resulting from environmental temperature changes. We realized WSNs with near-zero standby power consumption by integrating the infrared switch, sensors, and wireless communication module. When the target infrared signal appears, the WSNs are woken and show superb visual/auditory sensing performance. This work provides a novel approach for greatly lengthening the lifespan of unattended WSNs.</p>","PeriodicalId":18560,"journal":{"name":"Microsystems & Nanoengineering","volume":null,"pages":null},"PeriodicalIF":7.3,"publicationDate":"2024-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11366745/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142109356","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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":"Thermo-optical tweezers based on photothermal waveguides.","authors":"Fuwang Li, Jian Wei, Xiaomei Qin, Xue Chen, Dawei Chen, Wentao Zhang, Jiaguang Han, Libo Yuan, Hongchang Deng","doi":"10.1038/s41378-024-00757-7","DOIUrl":"10.1038/s41378-024-00757-7","url":null,"abstract":"<p><p>Field-controlled micromanipulation represents a pivotal technique for handling microparticles, yet conventional methods often risk physical damage to targets. Here, we discovered a completely new mechanism for true noncontact manipulation through photothermal effects, called thermal-optical tweezers. We employ a laser self-assembly photothermal waveguide (PTW) for dynamic microparticle manipulation. This waveguide demonstrates superior photothermal conversion and precision control, generating a nonisothermal temperature field. The interaction of thermal convection and thermophoresis within this field creates a microfluidic potential well, enabling noncontact and nondestructive particle manipulation. By varying the path of PTWs in lithography and manipulating laser loading modes, diverse manipulation strategies, such as Z-shaped migration, periodic oscillation, and directional transport, are achievable. Our innovative noninvasive micromanipulation technology minimizes not only physical damage to target objects but also enables precise and diverse manipulation of micro entities, opening up new avenues for the photothermal control of cells and biomolecules.</p>","PeriodicalId":18560,"journal":{"name":"Microsystems & Nanoengineering","volume":null,"pages":null},"PeriodicalIF":7.3,"publicationDate":"2024-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11368956/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142120220","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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":"Ultrasensitive SERF atomic magnetometer with a miniaturized hybrid vapor cell.","authors":"Yintao Ma, Yao Chen, Mingzhi Yu, Yanbin Wang, Shun Lu, Ju Guo, Guoxi Luo, Libo Zhao, Ping Yang, Qijing Lin, Zhuangde Jiang","doi":"10.1038/s41378-024-00758-6","DOIUrl":"https://doi.org/10.1038/s41378-024-00758-6","url":null,"abstract":"<p><p>The chip-scale hybrid optical pumping spin-exchange relaxation-free (SERF) atomic magnetometer with a single-beam arrangement has prominent applications in biomagnetic measurements because of its outstanding features, including ultrahigh sensitivity, an enhanced signal-to-noise ratio, homogeneous spin polarization and a much simpler optical configuration than other devices. In this work, a miniaturized single-beam hybrid optical pumping SERF atomic magnetometer based on a microfabricated atomic vapor cell is demonstrated. Although the optically thin Cs atoms are spin-polarized, the dense Rb atoms determine the experimental results. The enhanced signal strength and narrowed resonance linewidth are experimentally proven, which shows the superiority of the proposed magnetometer scheme. By using a differential detection scheme, we effectively suppress optical noise with an approximate five-fold improvement. Moreover, the cell temperature markedly affects the performance of the magnetometer. We systematically investigate the effects of temperature on the magnetometer parameters. The theoretical basis for these effects is explained in detail. The developed miniaturized magnetometer has an optimal magnetic sensitivity of 20 fT/Hz^1/2. The presented work provides a foundation for the chip-scale integration of ultrahighly sensitive quantum magnetometers that can be used for forward-looking magnetocardiography (MCG) and magnetoencephalography (MEG) applications.</p>","PeriodicalId":18560,"journal":{"name":"Microsystems & Nanoengineering","volume":null,"pages":null},"PeriodicalIF":7.3,"publicationDate":"2024-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11364876/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142109355","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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":"Functionalized monodisperse microbubble production: microfluidic method for fast, controlled, and automated removal of excess coating material.","authors":"M R P van den Broek, M Versluis, A van den Berg, T Segers","doi":"10.1038/s41378-024-00760-y","DOIUrl":"https://doi.org/10.1038/s41378-024-00760-y","url":null,"abstract":"<p><p>Functionalized monodisperse microbubbles have the potential to boost the sensitivity and efficacy of molecular ultrasound imaging and targeted drug delivery using bubbles and ultrasound. Monodisperse bubbles can be produced in a microfluidic flow focusing device. However, their functionalization and sequential use require removal of the excess lipids from the bubble suspension to minimize the use of expensive ligands and to avoid competitive binding and blocking of the receptor molecules. To date, excess lipid removal is performed by centrifugation, which is labor intensive and challenging to automate. More importantly, as we show, the increased hydrostatic pressure during centrifugation can reduce bubble monodispersity. Here, we introduce a novel automated microfluidic 'washing' method. First, bubbles are injected in a microfluidic chamber 1 mm in height where they are left to float against the top wall. Second, lipid-free medium is pumped through the chamber to remove excess lipids while the bubbles remain located at the top wall. Third, the washed bubbles are resuspended and removed from the device into a collection vial. We demonstrate that the present method can (i) reduce the excess lipid concentration by 4 orders of magnitude, (ii) be fully automated, and (iii) be performed in minutes while the size distribution, functionality, and acoustic response of the bubbles remain unaffected. Thus, the presented method is a gateway to the fully automated production of functionalized monodisperse microbubbles.</p>","PeriodicalId":18560,"journal":{"name":"Microsystems & Nanoengineering","volume":null,"pages":null},"PeriodicalIF":7.3,"publicationDate":"2024-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11364838/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142109354","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"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":"Fully tunable Fabry-Pérot cavity based on MEMS Sagnac loop reflector with ultra-low static power consumption.","authors":"Young Jae Park, Man Jae Her, Youngjae Jeong, Dong Ju Choi, Dong Uk Kim, Min Gi Lim, Myung Seok Hong, Hyug Su Kwon, Kyoungsik Yu, Sangyoon Han","doi":"10.1038/s41378-024-00728-y","DOIUrl":"https://doi.org/10.1038/s41378-024-00728-y","url":null,"abstract":"<p><p>The Fabry-Pérot interferometer, a fundamental component in optoelectronic systems, offers interesting applications such as sensors, lasers, and filters. In this work, we show a tunable Fabry-Pérot cavity consisting of tunable Sagnac loop reflectors (SLRs) and phase shifters based on electrostatic microelectromechanical (MEMS) actuator. The fabrication process of the device is compatible with the standard wafer-level silicon photonics fabrication processes. This electrostatic actuation mechanism provides well-balanced, scalable pathways for efficient tuning methodologies. The extinction ratio of the continuously tunable SLRs' reflectivity is larger than 20 dB. Full 2π phase shifting is achieved, and response times of all the components are less than 25 μs. Both actuators have extremely low static power, measuring under 20 fW and the energy needed for tuning is both below 20 pJ.</p>","PeriodicalId":18560,"journal":{"name":"Microsystems & Nanoengineering","volume":null,"pages":null},"PeriodicalIF":7.3,"publicationDate":"2024-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11362568/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142109353","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}