Jiyoung Song, Hoon Eui Jeong, Andrew Choi, Hong Nam Kim
Though animal models are still the gold standard for fundamental biological studies and drug evaluation for brain diseases, concerns arise from an apparent lack of reflecting the human genetics and pathophysiology. Recently, human avatars such as brain-on-a-chip and brain organoids which are generated in a 3D manner using multiple types of human-originated cells have risen as alternative testing models. Particularly in monitoring the functional neuronal cells that express action potentials in brain-on-a-chip or brain organoids, various methods of measuring their electrophysiological function have been suggested for the study of brain-related disease. Recent methodologies for analyzing the electrophysiology of different types of cells in brain-on-a-chip and brain organoids are summarized in this review. We first emphasize the inherent features of brain-on-a-chip and brain organoids from the perspective of the cell culture environment and accessibility to cells in the deep layer. The applicable monitoring techniques are then overviewed based on these features. Finally, we discuss the unmet needs for electrophysiology monitoring in advanced human brain avatar models.
{"title":"Monitoring of Electrophysiological Functions in Brain-on-a-Chip and Brain Organoids","authors":"Jiyoung Song, Hoon Eui Jeong, Andrew Choi, Hong Nam Kim","doi":"10.1002/anbr.202400052","DOIUrl":"10.1002/anbr.202400052","url":null,"abstract":"<p>Though animal models are still the gold standard for fundamental biological studies and drug evaluation for brain diseases, concerns arise from an apparent lack of reflecting the human genetics and pathophysiology. Recently, human avatars such as brain-on-a-chip and brain organoids which are generated in a 3D manner using multiple types of human-originated cells have risen as alternative testing models. Particularly in monitoring the functional neuronal cells that express action potentials in brain-on-a-chip or brain organoids, various methods of measuring their electrophysiological function have been suggested for the study of brain-related disease. Recent methodologies for analyzing the electrophysiology of different types of cells in brain-on-a-chip and brain organoids are summarized in this review. We first emphasize the inherent features of brain-on-a-chip and brain organoids from the perspective of the cell culture environment and accessibility to cells in the deep layer. The applicable monitoring techniques are then overviewed based on these features. Finally, we discuss the unmet needs for electrophysiology monitoring in advanced human brain avatar models.</p>","PeriodicalId":29975,"journal":{"name":"Advanced Nanobiomed Research","volume":"4 9","pages":""},"PeriodicalIF":4.0,"publicationDate":"2024-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/anbr.202400052","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141810992","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Mahdi Ayoubi, Richard Weinkamer, Alexander F. van Tol, Maximilian Rummler, Paul Roschger, Peter C. Brugger, Andrea Berzlanovich, Luca Bertinetti, Andreas Roschger, Peter Fratzl
For a better understanding of living tissues and materials, it is essential to study the intricate spatial relationship between cells and their surrounding tissue on the nanoscale, with a need for 3D, high-resolution imaging techniques. In the case of bone, focused ion beam-scanning electron microscopy (FIB-SEM) operated in the backscattered electron (BSE) mode proves to be a suitable method to image mineralized areas with a nominal resolution of 5 nm. However, as clinically relevant samples are often resin-embedded, the lack of atomic number (Z) contrast makes it difficult to distinguish the embedding material from unmineralized parts of the tissue, such as osteoid, in BSE images. Staining embedded samples with iodine vapor has been shown to be effective in revealing osteoid microstructure by 2D BSE imaging. Based on this idea, an iodine (Z = 53) staining protocol is developed for 3D imaging with FIB-SEM, investigating how the amount of iodine and exposure time influences the imaging outcome. Bone samples stained with this protocol also remain compatible with confocal laser scanning microscopy to visualize the lacunocanalicular network. The proposed protocol can be applied for 3D imaging of tissues exhibiting mineralized and nonmineralized regions to study physiological and pathological biomineralization.
{"title":"Postembedding Iodine Staining for Contrast-Enhanced 3D Imaging of Bone Tissue Using Focused Ion Beam-Scanning Electron Microscopy","authors":"Mahdi Ayoubi, Richard Weinkamer, Alexander F. van Tol, Maximilian Rummler, Paul Roschger, Peter C. Brugger, Andrea Berzlanovich, Luca Bertinetti, Andreas Roschger, Peter Fratzl","doi":"10.1002/anbr.202400035","DOIUrl":"10.1002/anbr.202400035","url":null,"abstract":"<p>For a better understanding of living tissues and materials, it is essential to study the intricate spatial relationship between cells and their surrounding tissue on the nanoscale, with a need for 3D, high-resolution imaging techniques. In the case of bone, focused ion beam-scanning electron microscopy (FIB-SEM) operated in the backscattered electron (BSE) mode proves to be a suitable method to image mineralized areas with a nominal resolution of 5 nm. However, as clinically relevant samples are often resin-embedded, the lack of atomic number (<i>Z</i>) contrast makes it difficult to distinguish the embedding material from unmineralized parts of the tissue, such as osteoid, in BSE images. Staining embedded samples with iodine vapor has been shown to be effective in revealing osteoid microstructure by 2D BSE imaging. Based on this idea, an iodine (<i>Z</i> = 53) staining protocol is developed for 3D imaging with FIB-SEM, investigating how the amount of iodine and exposure time influences the imaging outcome. Bone samples stained with this protocol also remain compatible with confocal laser scanning microscopy to visualize the lacunocanalicular network. The proposed protocol can be applied for 3D imaging of tissues exhibiting mineralized and nonmineralized regions to study physiological and pathological biomineralization.</p>","PeriodicalId":29975,"journal":{"name":"Advanced Nanobiomed Research","volume":"4 10","pages":""},"PeriodicalIF":4.0,"publicationDate":"2024-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/anbr.202400035","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141829609","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Magnetic nanomaterials, distinguished by their unique magnetic phenomena, particularly their magnetically actuated capabilities, have found widespread application in the field of nanomedicine. Compared with alternative driving mechanisms, magnetic actuation as a remote, highly permeable, and precisely controllable driving strategy endows nanomaterials with temporal and spatia mobility, making it possible to initiate and cease multiple forms of movement in vivo at will. When coupled with cutting-edge diagnostic and treating techniques including but not limited to magnetic resonance imaging, magnetothermal therapy, and magnetoelectric stimulation, magnetically actuated nanomaterials offer the potential for visual analysis, provision of reliable molecular information, and effective disease or tissue damage intervention. This review comprehensively outlines the synthesis methodologies, functional strategies, and biomedical applications of magnetically actuated nanomaterials within nanomedicine. Additionally, the future developments and applications of biocompatible magnetically actuated nanomaterials, especially in response to time-varying magnetic fields, are anticipated.
{"title":"Magnetically Actuated Nanomaterials in Biomedical Applications","authors":"Jiaxiang Xiao, Qian Dong, Yiting Xu, Changwen Li, Jiayu Zeng, Xin Xia, Xiangxian Meng, Zhuo Chen","doi":"10.1002/anbr.202300136","DOIUrl":"10.1002/anbr.202300136","url":null,"abstract":"<p>Magnetic nanomaterials, distinguished by their unique magnetic phenomena, particularly their magnetically actuated capabilities, have found widespread application in the field of nanomedicine. Compared with alternative driving mechanisms, magnetic actuation as a remote, highly permeable, and precisely controllable driving strategy endows nanomaterials with temporal and spatia mobility, making it possible to initiate and cease multiple forms of movement in vivo at will. When coupled with cutting-edge diagnostic and treating techniques including but not limited to magnetic resonance imaging, magnetothermal therapy, and magnetoelectric stimulation, magnetically actuated nanomaterials offer the potential for visual analysis, provision of reliable molecular information, and effective disease or tissue damage intervention. This review comprehensively outlines the synthesis methodologies, functional strategies, and biomedical applications of magnetically actuated nanomaterials within nanomedicine. Additionally, the future developments and applications of biocompatible magnetically actuated nanomaterials, especially in response to time-varying magnetic fields, are anticipated.</p>","PeriodicalId":29975,"journal":{"name":"Advanced Nanobiomed Research","volume":"4 8","pages":""},"PeriodicalIF":4.0,"publicationDate":"2024-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/anbr.202300136","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141828085","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}