Xuanxu Nan, Yiyang Wu, Lingyi Xu, Li Yang, Yue Cui
{"title":"A novel glass chip based lateral flow immunoassay of albumin","authors":"Xuanxu Nan, Yiyang Wu, Lingyi Xu, Li Yang, Yue Cui","doi":"10.1007/s10544-025-00744-3","DOIUrl":"10.1007/s10544-025-00744-3","url":null,"abstract":"<div><p>Lateral flow immunoassays typically rely on optical tests conducted on paper strips. However, the 3D matrix of paper embedded with optical nanoparticles often limits detection sensitivity and the ability of detection instruments to capture signals. This study introduces a novel approach using a glass chip-based lateral flow immunoassay, with albumin as a typical biomarker for detection, enabling the presence of the signal on a flat surface. Compared with traditional paper-based immunoassay, glass-based lateral flow immunoassay has achieved a uniform distribution pattern for albumin detection, lowered the limit of detection from 100 ng/mL to 1 ng/mL, and reduced detection time through an improved liquid mobility system. The glass-based method also shortens the detection time by 28.5% to 147.8 s compared to the traditional method. This research presents a new methodology for lateral flow immunoassays that can be applied to a wide range of biomarkers, with potential benefits for various medical and environmental applications.</p></div>","PeriodicalId":490,"journal":{"name":"Biomedical Microdevices","volume":"27 2","pages":""},"PeriodicalIF":3.0,"publicationDate":"2025-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10544-025-00744-3.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143707111","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Rodrigo S. Wiederkehr, Elisabeth Marchal, Maarten Fauvart, Tomas Forceville, Ahmed Taher, Tim Steylaerts, YoungJae Choe, Hans Dusar, Silvia Lenci, Eleni Siouti, Vassiliki T. Potsika, Evangelos Andreakos, Tim Stakenborg
{"title":"A capillary-driven microfluidic device for performing spatial multiplex PCR","authors":"Rodrigo S. Wiederkehr, Elisabeth Marchal, Maarten Fauvart, Tomas Forceville, Ahmed Taher, Tim Steylaerts, YoungJae Choe, Hans Dusar, Silvia Lenci, Eleni Siouti, Vassiliki T. Potsika, Evangelos Andreakos, Tim Stakenborg","doi":"10.1007/s10544-025-00745-2","DOIUrl":"10.1007/s10544-025-00745-2","url":null,"abstract":"<div><p>Multiplex polymerase chain reaction (PCR) tests multiple biomarkers or pathogens that cause overlapping symptoms, making it an essential tool in syndromic testing. To achieve a multiplex PCR on chip, a design based on capillary-driven fluidic actuation is proposed. Our silicon chip features 22 reaction chambers and allows primers and probes to be pre-spotted in the reaction chambers prior to use. The design facilitates rapid sample loading through a common inlet channel, delivering reagents to all reaction chambers in less than 10 s. A custom clamping mechanism combined with a double depth cavity design ensures proper sealing during temperature cycling without the need for extra reagents like oil. Temperature cycling and fluorescence imaging were performed using custom-made hardware. As a proof of concept, two single nucleotide polymorphisms (SNPs), CyP2C19*2 and PCSK9 were detected. These results demonstrate the feasibility of on-chip multiplex PCR, compatible with different assays in parallel and requiring only a single pipetting step for reagent loading, without active fluidic actuation like pumping.</p></div>","PeriodicalId":490,"journal":{"name":"Biomedical Microdevices","volume":"27 2","pages":""},"PeriodicalIF":3.0,"publicationDate":"2025-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10544-025-00745-2.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143706955","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Brenda F. M. Castro, Raquel G. Arribada, Thomas T. Inoue, Elias R. Filho, Bruno C. Sena, Luiz F. L. Ferreira, Silvia L. Fialho, Armando Silva-Cunha
{"title":"New intraocular lens containing a drug delivery system (IOL-DDS) loaded with dexamethasone","authors":"Brenda F. M. Castro, Raquel G. Arribada, Thomas T. Inoue, Elias R. Filho, Bruno C. Sena, Luiz F. L. Ferreira, Silvia L. Fialho, Armando Silva-Cunha","doi":"10.1007/s10544-025-00743-4","DOIUrl":"10.1007/s10544-025-00743-4","url":null,"abstract":"<div><p>This study demonstrates the development of polymeric PLGA (50:50) nanoparticles containing dexamethasone acetate, which are dispersed in a PVA film and added to hydrophobic intraocular lenses (IOL) exclusively designed for this application. The resulting IOL-drug delivery system (IOL-DDS) can be introduced into the eye with syringe-type injectors and standard surgical techniques. The obtained results showed that the lens design does not compromise stability within the eye or weaken the loops, preserves its optical zone, and maintains injector’s functionality during surgery. The IOL-DDS releases the drug in vivo for 7 days within the therapeutic concentration range. Short-term assessment confirms the safety of the developed device for ocular structures, which is supported by slit lamp observations, intraocular pressure measurements, optical coherence tomography, and histological analysis. Minor changes in specular microscopy parameters are observed and may be related to the use of IOL and surgical instruments designed for human eyes in smaller rabbit eyes.</p></div>","PeriodicalId":490,"journal":{"name":"Biomedical Microdevices","volume":"27 2","pages":""},"PeriodicalIF":3.0,"publicationDate":"2025-03-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143676339","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A spiral channel with integrated microelectrodes for label-free particle lateral position and size characterization","authors":"Yunhao Peng, Bruce K. Gale, Himanshu J. Sant","doi":"10.1007/s10544-025-00742-5","DOIUrl":"10.1007/s10544-025-00742-5","url":null,"abstract":"<p>Modified-trident shaped microelectrodes were incorporated into a spiral-shaped microfluidic focusing channel, utilizing impedance flow cytometry to analyze and quantify inertial microfluidic-based separation of homogeneous particles differing in size. Double peak voltage pulses were generated as particles moved across the electrodes, where the ratio of the peak amplitudes indicated the lateral particle positions inside the channel at various flow rates, while the peak amplitude indicated particle size and vertical position. The root mean square error between the optical and electrical position measurements was 11.44 µm reflecting the lateral position measurement resolution. The peak amplitudes were used to estimate particle size after being adjusted to account for particle vertical position using a shape parameter, which effectively reduced errors in particle size calculations. The particle size estimate sensitivity was measured to be 2.15 μm/mV from the peak amplitudes. The electrodes with the appropriate signal processing were able to detect both the size and location of particles after separation with a spiral channel, showing their utility in potentially controlling the separation conditions for these devices.</p>","PeriodicalId":490,"journal":{"name":"Biomedical Microdevices","volume":"27 2","pages":""},"PeriodicalIF":3.0,"publicationDate":"2025-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143638325","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Lab-on-a-chip device for microfluidic trapping and TIRF imaging of single cells","authors":"Dustin Dzikonski, Riccardo Zamboni, Aniket Bandyopadhyay, Deepthi Paul, Roland Wedlich-Söldner, Cornelia Denz, Jörg Imbrock","doi":"10.1007/s10544-025-00739-0","DOIUrl":"10.1007/s10544-025-00739-0","url":null,"abstract":"<p>Total internal reflection fluorescence (TIRF) microscopy is a powerful imaging technique that visualizes the outer surface of specimens in close proximity to a substrate, yielding crucial insights in cell membrane compositions. TIRF plays a key role in single-cell studies but typically requires chemical fixation to ensure direct contact between the cell membrane and substrate, which can compromise cell viability and promote clustering. In this study, we present a microfluidic device with structures designed to trap single yeast cells and fix them in direct contact with the substrate surface to enable TIRF measurements on the cell membrane. The traps are fabricated using two-photon polymerization, allowing high-resolution printing of intricate structures that encapsulate cells in all three dimensions while maintaining exposure to the flow within the device. Our adaptable trap design allows us to reduce residual movement of trapped cells to a minimum while maintaining high trapping efficiencies. We identify the optimal structure configuration to trap single yeast cells and demonstrate that trapping efficiency can be tuned by modifying cell concentration and injection methods. Additionally, by replicating the cell trap design with soft hydrogel materials, we demonstrate the potential of our approach for further single-cell studies. The authors have no relevant financial or non-financial interests to disclose and no competing interests to declare.</p>","PeriodicalId":490,"journal":{"name":"Biomedical Microdevices","volume":"27 1","pages":""},"PeriodicalIF":3.0,"publicationDate":"2025-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10544-025-00739-0.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143621794","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Wei Xu, Dan Meng, Ming Li, Qingwei Song, Wenling Wu, Yimeng Bi, Chenyu Xu, Yifei Zhang, Dingqiang Lu
{"title":"Deciphering the allosteric dynamics of GPR120-fatty acid interactions within a bilayer nanogold electrochemical receptor biosensor: the impact of replacing tryptophan 198 with proline","authors":"Wei Xu, Dan Meng, Ming Li, Qingwei Song, Wenling Wu, Yimeng Bi, Chenyu Xu, Yifei Zhang, Dingqiang Lu","doi":"10.1007/s10544-025-00736-3","DOIUrl":"10.1007/s10544-025-00736-3","url":null,"abstract":"<div><p>GPR120 is a free fatty acid receptor capable of signalling excess fatty acids. GPR120 can be activated by various types of free fatty acids, causing intracellular signal transduction and exerting energy regulation, immune homeostasis, and neuronal functions. It has been suggested that Trp198 may be an important residue in the recognition and activation of GPR120 by fatty acid ligands, but direct experimental evidence is lacking. In this study, a GPR120-based bilayer gold nanoparticle biosensor (Trp198→Pro) was constructed by genetically manipulating Trp198 on GPR120 by replacing it with proline for the determination of linkage variability between 14 naturally occurring fatty acid ligands and mutant receptors. The results showed that both before and after amino acid substitution the GPR120 bilayer nanogold receptor sensor responded to all 14 natural fatty acid ligands. And the linkage transformation constants of crotonic acid, dodecanoic acid, oleic acid, linoleic acid, α-linolenic acid, and DHA decreased after Trp198 was replaced by Pro. To further reveal its molecular recognition mechanism, molecular simulation docking experiments were performed on GPR120 and 14 fatty acid ligand compounds before and after amino acid substitutions, respectively. The results showed that before and after the amino acid substitutions, the binding conformational affinity values of GPR120 docked with the ligands were negative, implying that these fatty acid ligands can spontaneously bind to the active pocket of GPR120 without absorbing external energy. Upon replacement of Trp198 by Pro, the active pocket of GPR120 at the optimal docking site with the fatty acid ligand is altered, leading to changes in the amino acid residues that exert the interaction. The above results demonstrate that Trp198 indeed plays an important role in the recognition of fatty acid ligands on GPR120. The present study provides direct quantitative evidence for the roles played by different amino acid residues in receptor-ligand recognition and interaction. At the same time, it provides new ideas for the study of other receptor-ligand-linked metastable mechanisms and kinetic laws.</p></div>","PeriodicalId":490,"journal":{"name":"Biomedical Microdevices","volume":"27 1","pages":""},"PeriodicalIF":3.0,"publicationDate":"2025-03-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143571143","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Microfluidic biosensors: revolutionizing detection in DNA analysis, cellular analysis, and pathogen detection","authors":"Reza Didarian, Mehdi Tayybi Azar","doi":"10.1007/s10544-025-00741-6","DOIUrl":"10.1007/s10544-025-00741-6","url":null,"abstract":"<div><p>Microfluidic chips have emerged as versatile and powerful tools that enable the precise manipulation of fluids and bioparticles at the microscale. Their impact on detection applications is profound, offering advantages such as miniaturization, enhanced sensitivity, multiplexing capability, and integrated functions. These chips can be customized for specific techniques, such as DNA analysis, immunoassays, chemical sensing, and cell-based assays. With a wide range of types available, including Lab-on-a-Chip, droplet-based, paper-based, electrochemical, optical, and magnetic chips, they find applications in diverse fields such as medical diagnostics, DNA analysis, cell analysis, food safety testing, environmental monitoring, and industrial processes. This powerful technology replicates laboratory capabilities on miniature chip-scale devices, resulting in time and cost savings while enabling portability and field-use capability. Its impact spans genetic analysis, proteomic analysis, cell culture, biosensors, pathogen detection, and point-of-care diagnostics, playing a pivotal role in advancing chemical and biological analysis. The overall aim of this review is to provide an overview of the development of microfluidic biochips for biological detection and discuss their various applications.</p></div>","PeriodicalId":490,"journal":{"name":"Biomedical Microdevices","volume":"27 1","pages":""},"PeriodicalIF":3.0,"publicationDate":"2025-02-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143496952","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Om Prakash Singh, Ismail M. El-Badawy, Sornambikai Sundaram, Conor O’Mahony
{"title":"Microneedle electrodes: materials, fabrication methods, and electrophysiological signal monitoring-narrative review","authors":"Om Prakash Singh, Ismail M. El-Badawy, Sornambikai Sundaram, Conor O’Mahony","doi":"10.1007/s10544-024-00732-z","DOIUrl":"10.1007/s10544-024-00732-z","url":null,"abstract":"<div><p>Flexible, microneedle-based electrodes offer an innovative solution for high-quality physiological signal monitoring, reducing the need for complex algorithms and hardware, thus streamlining health assessments, and enabling earlier disease detection. These electrodes are particularly promising for improving patient outcomes by providing more accurate, reliable, and long-term electrophysiological data, but their clinical adoption is hindered by the limited availability of large-scale population testing. This review examines the key advantages of flexible microneedle electrodes, including their ability to conform to the skin, enhance skin-electrode contact, reduce discomfort, and deliver superior signal fidelity. The mechanical and electrical properties of these electrodes are thoroughly explored, focusing on critical aspects like fracture force, skin penetration efficiency, and impedance measurements. Their applications in capturing electrophysiological signals such as ECG, EMG, and EEG are also highlighted, demonstrating their potential in clinical scenarios. Finally, the review outlines future research directions, emphasizing the importance of further studies to enhance the clinical and consumer use of flexible microneedle electrodes in medical diagnostics.</p></div>","PeriodicalId":490,"journal":{"name":"Biomedical Microdevices","volume":"27 1","pages":""},"PeriodicalIF":3.0,"publicationDate":"2025-02-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143489552","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Reza Mahdavi, Sameereh Hashemi-Najafabadi, Mohammad Adel Ghiass, Silmu Valaskivi, Hannu Välimäki, Joose Kreutzer, Charlotte Hamngren Blomqvist, Stefano Romeo, Pasi Kallio, Caroline Beck Adiels
{"title":"Design, fabrication, and characterization of a user-friendly microfluidic device for studying liver zonation-on-chip (ZoC)","authors":"Reza Mahdavi, Sameereh Hashemi-Najafabadi, Mohammad Adel Ghiass, Silmu Valaskivi, Hannu Välimäki, Joose Kreutzer, Charlotte Hamngren Blomqvist, Stefano Romeo, Pasi Kallio, Caroline Beck Adiels","doi":"10.1007/s10544-025-00738-1","DOIUrl":"10.1007/s10544-025-00738-1","url":null,"abstract":"<div><p>Liver zonation is a fundamental characteristic of hepatocyte spatial heterogeneity, which is challenging to recapitulate in traditional cell cultures. This study presents a novel microfluidic device designed to induce zonation in liver cell cultures by establishing an oxygen gradient using standard laboratory gases. The device consists of two layers; a bottom layer containing a gas channel network that delivers high (cell incubator air, 19% oxygen) and low oxygenated (nitrogen) gases to create three distinct zones within the cell culture chamber in the layer above. Computational simulations and ratiometric oxygen sensing were employed to validate the oxygen gradient, demonstrating that stable oxygen levels were achieved within two hours. Liver zonation was confirmed using immunofluorescence staining, which showed zonated albumin production in HepG2 cells directly correlating with oxygen levels and mimicking <i>in-vivo</i> zonation behavior. This user-friendly device supports studies on liver zonation and related metabolic disease mechanisms <i>in vitro</i>. It can also be utilized for experiments that necessitate precise gas concentration gradients, such as hypoxia-related research areas focused on angiogenesis and cancer development.</p></div>","PeriodicalId":490,"journal":{"name":"Biomedical Microdevices","volume":"27 1","pages":""},"PeriodicalIF":3.0,"publicationDate":"2025-02-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10544-025-00738-1.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143423157","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Electrical stimulation of neuroretinas with 3D pyrolytic carbon electrodes","authors":"Pratik Kusumanchi, Jesper Guldsmed Madsen, Toke Bek, Stephan Sylvest Keller, Rasmus Schmidt Davidsen","doi":"10.1007/s10544-024-00729-8","DOIUrl":"10.1007/s10544-024-00729-8","url":null,"abstract":"<div><p>Retinal prosthesis has been one of the medical strategies aimed at restoring some degree of vision for patients affected by retinal degenerative diseases, such as Retinitis Pigmentosa (RP) and age-related macular degeneration (AMD), which are leading causes of irreversible visual loss. In retinal prosthesis, electrical pulses are typically delivered to the retinal neurons via electrodes on the surface of the implant. In this work, we fabricated 3D carbon pillar electrodes by pyrolysis of SU-8 structures defined photolithographically on Si wafers. We then measured compound action potentials induced in porcine neuroretinas stimulated with electrical pulses. The recorded spikes were validated to be biological in origin by adding the voltage-gated sodium-channel blocking agent tetrodotoxin. The minimum threshold voltage needed to effectively stimulate retinal cells, such as retinal ganglion cells, with 3D electrodes was analyzed through systematic investigation of the spike rate and amplitudes as a function of stimulation voltage. 3D electrodes significantly increased spike rate and amplitudes above spontaneous activity in the tissue during stimulation and outperformed the 2D counterpart, both in terms of spike rate and amplitude. Our results indicate a threshold voltage range of 500-600 mV for 1 ms pulses at a frequency of 10 Hz above which a significant increase in spike count was observed. Furthermore, we report an order of magnitude increase in peak-to-peak amplitude for evoked spikes (> 3 mV), compared to spontaneous spikes (∼ 200 µV). Based on numerical integration, we estimate the area under the curve to be ~14 times larger in evoked compound action potentials compared to spontaneous activity. This indicates the relative increase in number of contributing cells to the compound action potential. At a stimulation voltage of 600 mV the spike rate for 3D electrodes was above 10 spikes/channel/s. We hypothesize that the significant difference between 2D and 3D electrodes is not only caused by the higher active electrode surface area of the 3D micropillar electrodes, but also by more intricate contact and interaction with the inner cell layers of the retinal tissue. Our findings indicate that 3D carbon micropillar electrodes are promising for electrical stimulation of the retina.</p></div>","PeriodicalId":490,"journal":{"name":"Biomedical Microdevices","volume":"27 1","pages":""},"PeriodicalIF":3.0,"publicationDate":"2025-02-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10544-024-00729-8.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143388913","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}