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Rizzuti M, Melzi V, Brambilla L, Quetti L, Sali L, Ottoboni L, Meneri M, Ratti A, Verde F, Ticozzi N, Comi GP, Corti S, Abati E. Shaping the Neurovascular Unit Exploiting Human Brain Organoids. Mol Neurobiol 2024; 61:6642-6657. [PMID: 38334812 PMCID: PMC11338975 DOI: 10.1007/s12035-024-03998-9] [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: 04/14/2023] [Accepted: 01/29/2024] [Indexed: 02/10/2024]
Abstract
Brain organoids, three-dimensional cell structures derived from pluripotent stem cells, closely mimic key aspects of the human brain in vitro, providing a powerful tool for studying neurodevelopment and disease. The neuroectodermal induction protocol employed for brain organoid generation primarily gives rise to the neural cellular component but lacks the vital vascular system, which is crucial for the brain functions by regulating differentiation, migration, and circuit formation, as well as delivering oxygen and nutrients. Many neurological diseases are caused by dysfunctions of cerebral microcirculation, making vascularization of human brain organoids an important tool for pathogenetic and translational research. Experimentally, the creation of vascularized brain organoids has primarily focused on the fusion of vascular and brain organoids, on organoid transplantation in vivo, and on the use of microfluidic devices to replicate the intricate microenvironment of the human brain in vitro. This review summarizes these efforts and highlights the importance of studying the neurovascular unit in a forward-looking perspective of leveraging their use for understanding and treating neurological disorders.
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Affiliation(s)
- Mafalda Rizzuti
- Neurology Unit, Foundation IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Valentina Melzi
- Neurology Unit, Foundation IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Lorenzo Brambilla
- Neurology Unit, Foundation IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Lorenzo Quetti
- Neurology Unit, Foundation IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Luca Sali
- Neurology Unit, Foundation IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Linda Ottoboni
- Dino Ferrari Centre, Department of Pathophysiology and Transplantation (DEPT), Università degli Studi di Milano, Milan, Italy
| | - Megi Meneri
- Dino Ferrari Centre, Department of Pathophysiology and Transplantation (DEPT), Università degli Studi di Milano, Milan, Italy
| | - Antonia Ratti
- Department of Neurology and Laboratory of Neuroscience, IRCCS Istituto Auxologico Italiano, Milan, Italy
- Department Medical Biotechnology and Translational Medicine, Università degli Studi di Milano, Milan, Italy
| | - Federico Verde
- Dino Ferrari Centre, Department of Pathophysiology and Transplantation (DEPT), Università degli Studi di Milano, Milan, Italy
- Department of Neurology and Laboratory of Neuroscience, IRCCS Istituto Auxologico Italiano, Milan, Italy
| | - Nicola Ticozzi
- Dino Ferrari Centre, Department of Pathophysiology and Transplantation (DEPT), Università degli Studi di Milano, Milan, Italy
- Department of Neurology and Laboratory of Neuroscience, IRCCS Istituto Auxologico Italiano, Milan, Italy
| | - Giacomo Pietro Comi
- Neurology Unit, Foundation IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
- Dino Ferrari Centre, Department of Pathophysiology and Transplantation (DEPT), Università degli Studi di Milano, Milan, Italy
| | - Stefania Corti
- Dino Ferrari Centre, Department of Pathophysiology and Transplantation (DEPT), Università degli Studi di Milano, Milan, Italy
- Neuromuscular and Rare Diseases Unit, Department of Neuroscience, Foundation IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Elena Abati
- Dino Ferrari Centre, Department of Pathophysiology and Transplantation (DEPT), Università degli Studi di Milano, Milan, Italy.
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Rasouli A, Roshangar L, Hosseini M, Pourmohammadfazel A, Nikzad S. Beyond boundaries: The therapeutic potential of exosomes in neural microenvironments in neurological disorders. Neuroscience 2024; 553:98-109. [PMID: 38964450 DOI: 10.1016/j.neuroscience.2024.06.031] [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: 12/30/2023] [Revised: 06/18/2024] [Accepted: 06/25/2024] [Indexed: 07/06/2024]
Abstract
Neurological disorders are a diverse group of conditions that can significantly impact individuals' quality of life. The maintenance of neural microenvironment homeostasis is essential for optimal physiological cellular processes. Perturbations in this delicate balance underlie various pathological manifestations observed across various neurological disorders. Current treatments for neurological disorders face substantial challenges, primarily due to the formidable blood-brain barrier and the intricate nature of neural tissue structures. These obstacles have resulted in a paucity of effective therapies and inefficiencies in patient care. Exosomes, nanoscale vesicles that contain a complex repertoire of biomolecules, are identifiable in various bodily fluids. They hold substantial promise in numerous therapeutic interventions due to their unique attributes, including targeted drug delivery mechanisms and the ability to cross the BBB, thereby enhancing their therapeutic potential. In this review, we investigate the therapeutic potential of exosomes across a range of neurological disorders, including neurodegenerative disorders, traumatic brain injury, peripheral nerve injury, brain tumors, and stroke. Through both in vitro and in vivo studies, our findings underscore the beneficial influence of exosomes in enhancing the neural microenvironment following neurological diseases, offering promise for improved neural recovery and management in these conditions.
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Affiliation(s)
- Arefe Rasouli
- Department of Anatomical Sciences, School of Medicine Tabriz University of Medical Sciences, Tabriz, Iran
| | - Leila Roshangar
- Department of Anatomical Sciences, School of Medicine Tabriz University of Medical Sciences, Tabriz, Iran.
| | - Mohammadbagher Hosseini
- Department of Pediatrics, School of Medicine Tabriz University of Medical Sciences, Tabriz, Iran
| | - Amir Pourmohammadfazel
- Department of Anatomical Sciences, School of Medicine Tabriz University of Medical Sciences, Tabriz, Iran
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Nishimura K, Osaki H, Tezuka K, Nakashima D, Numata S, Masamizu Y. Recent advances and applications of human brain models. Front Neural Circuits 2024; 18:1453958. [PMID: 39161368 PMCID: PMC11330844 DOI: 10.3389/fncir.2024.1453958] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2024] [Accepted: 07/25/2024] [Indexed: 08/21/2024] Open
Abstract
Recent advances in human pluripotent stem cell (hPSC) technologies have prompted the emergence of new research fields and applications for human neurons and brain organoids. Brain organoids have gained attention as an in vitro model system that recapitulates the higher structure, cellular diversity and function of the brain to explore brain development, disease modeling, drug screening, and regenerative medicine. This progress has been accelerated by abundant interactions of brain organoid technology with various research fields. A cross-disciplinary approach with human brain organoid technology offers a higher-ordered advance for more accurately understanding the human brain. In this review, we summarize the status of neural induction in two- and three-dimensional culture systems from hPSCs and the modeling of neurodegenerative diseases using brain organoids. We also highlight the latest bioengineered technologies for the assembly of spatially higher-ordered neural tissues and prospects of brain organoid technology toward the understanding of the potential and abilities of the human brain.
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Affiliation(s)
- Kaneyasu Nishimura
- Laboratory of Functional Brain Circuit Construction, Graduate School of Brain Science, Doshisha University, Kyotanabe, Japan
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Akolawala Q, Keuning F, Rovituso M, van Burik W, van der Wal E, Versteeg HH, Rondon AMR, Accardo A. Micro-Vessels-Like 3D Scaffolds for Studying the Proton Radiobiology of Glioblastoma-Endothelial Cells Co-Culture Models. Adv Healthc Mater 2024; 13:e2302988. [PMID: 37944591 PMCID: PMC11468971 DOI: 10.1002/adhm.202302988] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2023] [Revised: 10/30/2023] [Indexed: 11/12/2023]
Abstract
Glioblastoma (GBM) is a devastating cancer of the brain with an extremely poor prognosis. While X-ray radiotherapy and chemotherapy remain the current standard, proton beam therapy is an appealing alternative as protons can damage cancer cells while sparing the surrounding healthy tissue. However, the effects of protons on in vitro GBM models at the cellular level, especially when co-cultured with endothelial cells, the building blocks of brain micro-vessels, are still unexplored. In this work, novel 3D-engineered scaffolds inspired by the geometry of brain microvasculature are designed, where GBM cells cluster and proliferate. The architectures are fabricated by two-photon polymerization (2PP), pre-cultured with endothelial cells (HUVECs), and then cultured with a human GBM cell line (U251). The micro-vessel structures enable GBM in vivo-like morphologies, and the results show a higher DNA double-strand breakage in GBM monoculture samples when compared to the U251/HUVECs co-culture, with cells in 2D featuring a larger number of DNA damage foci when compared to cells in 3D. The discrepancy in terms of proton radiation response indicates a difference in the radioresistance of the GBM cells mediated by the presence of HUVECs and the possible induction of stemness features that contribute to radioresistance and improved DNA repair.
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Affiliation(s)
- Qais Akolawala
- Department of Precision and Microsystems EngineeringFaculty of MechanicalMaritime and Materials EngineeringDelft University of TechnologyMekelweg 22628 CDDelftThe Netherlands
- Holland Proton Therapy Center (HollandPTC)Huismansingel 42629 JHDelftThe Netherlands
| | - Floor Keuning
- Erasmus University CollegeNieuwemarkt 1A, Rotterdam3011 HPRotterdamThe Netherlands
| | - Marta Rovituso
- Holland Proton Therapy Center (HollandPTC)Huismansingel 42629 JHDelftThe Netherlands
| | - Wouter van Burik
- Holland Proton Therapy Center (HollandPTC)Huismansingel 42629 JHDelftThe Netherlands
| | - Ernst van der Wal
- Holland Proton Therapy Center (HollandPTC)Huismansingel 42629 JHDelftThe Netherlands
| | - Henri H. Versteeg
- Einthoven Laboratory for Vascular and Regenerative MedicineDivision of Thrombosis and HemostasisDepartment of Internal MedicineLeiden University Medical CenterAlbinusdreef 22333 ZALeidenThe Netherlands
| | - Araci M. R. Rondon
- Einthoven Laboratory for Vascular and Regenerative MedicineDivision of Thrombosis and HemostasisDepartment of Internal MedicineLeiden University Medical CenterAlbinusdreef 22333 ZALeidenThe Netherlands
| | - Angelo Accardo
- Department of Precision and Microsystems EngineeringFaculty of MechanicalMaritime and Materials EngineeringDelft University of TechnologyMekelweg 22628 CDDelftThe Netherlands
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Li M, Sun H, Hou Z, Hao S, Jin L, Wang B. Engineering the Physical Microenvironment into Neural Organoids for Neurogenesis and Neurodevelopment. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2024; 20:e2306451. [PMID: 37771182 DOI: 10.1002/smll.202306451] [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: 07/29/2023] [Revised: 09/04/2023] [Indexed: 09/30/2023]
Abstract
Understanding the signals from the physical microenvironment is critical for deciphering the processes of neurogenesis and neurodevelopment. The discovery of how surrounding physical signals shape human developing neurons is hindered by the bottleneck of conventional cell culture and animal models. Notwithstanding neural organoids provide a promising platform for recapitulating human neurogenesis and neurodevelopment, building neuronal physical microenvironment that accurately mimics the native neurophysical features is largely ignored in current organoid technologies. Here, it is discussed how the physical microenvironment modulates critical events during the periods of neurogenesis and neurodevelopment, such as neural stem cell fates, neural tube closure, neuronal migration, axonal guidance, optic cup formation, and cortical folding. Although animal models are widely used to investigate the impacts of physical factors on neurodevelopment and neuropathy, the important roles of human stem cell-derived neural organoids in this field are particularly highlighted. Considering the great promise of human organoids, building neural organoid microenvironments with mechanical forces, electrophysiological microsystems, and light manipulation will help to fully understand the physical cues in neurodevelopmental processes. Neural organoids combined with cutting-edge techniques, such as advanced atomic force microscopes, microrobots, and structural color biomaterials might promote the development of neural organoid-based research and neuroscience.
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Affiliation(s)
- Minghui Li
- Key Laboratory of Biorheological Science and Technology, Ministry of Education, College of Bioengineering, Chongqing University, Chongqing, 400045, China
- Southwest Hospital/Southwest Eye Hospital, Third Military Medical University (Army Medical University), Chongqing, 400038, China
| | - Heng Sun
- Key Laboratory of Biorheological Science and Technology, Ministry of Education, College of Bioengineering, Chongqing University, Chongqing, 400045, China
| | - Zongkun Hou
- Key Laboratory of Infectious Immune and Antibody Engineering of Guizhou Province, Engineering Research Center of Cellular Immunotherapy of Guizhou Province, School of Biology and Engineering/School of Basic Medical Sciences, Guizhou Medical University, Guiyang, 550025, China
| | - Shilei Hao
- Key Laboratory of Biorheological Science and Technology, Ministry of Education, College of Bioengineering, Chongqing University, Chongqing, 400045, China
| | - Liang Jin
- Key Laboratory of Biorheological Science and Technology, Ministry of Education, College of Bioengineering, Chongqing University, Chongqing, 400045, China
| | - Bochu Wang
- Key Laboratory of Biorheological Science and Technology, Ministry of Education, College of Bioengineering, Chongqing University, Chongqing, 400045, China
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Litowczenko J, Wychowaniec JK, Załęski K, Marczak Ł, Edwards-Gayle CJC, Tadyszak K, Maciejewska BM. Micro/nano-patterns for enhancing differentiation of human neural stem cells and fabrication of nerve conduits via soft lithography and 3D printing. BIOMATERIALS ADVANCES 2023; 154:213653. [PMID: 37862812 DOI: 10.1016/j.bioadv.2023.213653] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2023] [Revised: 10/02/2023] [Accepted: 10/06/2023] [Indexed: 10/22/2023]
Abstract
Topographical cues on materials can manipulate cellular fate, particularly for neural cells that respond well to such cues. Utilizing biomaterial surfaces with topographical features can effectively influence neuronal differentiation and promote neurite outgrowth. This is crucial for improving the regeneration of damaged neural tissue after injury. Here, we utilized groove patterns to create neural conduits that promote neural differentiation and axonal growth. We investigated the differentiation of human neural stem cells (NSCs) on silicon dioxide groove patterns with varying height-to-width/spacing ratios. We hypothesize that NSCs can sense the microgrooves with nanoscale depth on different aspect ratio substrates and exhibit different morphologies and differentiation fate. A comprehensive approach was employed, analyzing cell morphology, neurite length, and cell-specific markers. These aspects provided insights into the behavior of the investigated NSCs and their response to the topographical cues. Three groove-pattern models were designed with varying height-to-width/spacing ratios of 80, 42, and 30 for groove pattern widths of 1 μm, 5 μm, and 10 μm and nanoheights of 80 nm, 210 nm, and 280 nm. Smaller groove patterns led to longer neurites and more effective differentiation towards neurons, whereas larger patterns promoted multidimensional differentiation towards both neurons and glia. We transferred these cues onto patterned polycaprolactone (PCL) and PCL-graphene oxide (PCL-GO) composite 'stamps' using simple soft lithography and reproducible extrusion 3D printing methods. The patterned scaffolds elicited a response from NSCs comparable to that of silicon dioxide groove patterns. The smallest pattern stimulated the highest neurite outgrowth, while the middle-sized grooves of PCL-GO induced effective synaptogenesis. We demonstrated the potential for such structures to be wrapped into tubes and used as grafts for peripheral nerve regeneration. Grooved PCL and PCL-GO conduits could be a promising alternative to nerve grafting.
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Affiliation(s)
- Jagoda Litowczenko
- NanoBioMedical Centre, Adam Mickiewicz University, Wszechnicy Piastowskiej 3, PL61614 Poznań, Poland.
| | - Jacek K Wychowaniec
- NanoBioMedical Centre, Adam Mickiewicz University, Wszechnicy Piastowskiej 3, PL61614 Poznań, Poland; AO Research Institute Davos, Clavadelerstrasse 8, 7270 Davos, Switzerland
| | - Karol Załęski
- NanoBioMedical Centre, Adam Mickiewicz University, Wszechnicy Piastowskiej 3, PL61614 Poznań, Poland
| | - Łukasz Marczak
- European Centre for Bioinformatics and Genomics, Institute of Bioorganic Chemistry, Polish Academy of Sciences, Noskowskiego 12/14, 61-704 Poznań, Poland
| | | | - Krzysztof Tadyszak
- Institute of Macromolecular Chemistry, CAS, Heyrovského nám. 2, 162 06 Prague 6, Czech Republic
| | - Barbara M Maciejewska
- NanoBioMedical Centre, Adam Mickiewicz University, Wszechnicy Piastowskiej 3, PL61614 Poznań, Poland
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Kolotyeva NA, Gilmiyarova FN, Averchuk AS, Baranich TI, Rozanova NA, Kukla MV, Tregub PP, Salmina AB. Novel Approaches to the Establishment of Local Microenvironment from Resorbable Biomaterials in the Brain In Vitro Models. Int J Mol Sci 2023; 24:14709. [PMID: 37834155 PMCID: PMC10572431 DOI: 10.3390/ijms241914709] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2023] [Revised: 09/19/2023] [Accepted: 09/27/2023] [Indexed: 10/15/2023] Open
Abstract
The development of brain in vitro models requires the application of novel biocompatible materials and biopolymers as scaffolds for controllable and effective cell growth and functioning. The "ideal" brain in vitro model should demonstrate the principal features of brain plasticity like synaptic transmission and remodeling, neurogenesis and angiogenesis, and changes in the metabolism associated with the establishment of new intercellular connections. Therefore, the extracellular scaffolds that are helpful in the establishment and maintenance of local microenvironments supporting brain plasticity mechanisms are of critical importance. In this review, we will focus on some carbohydrate metabolites-lactate, pyruvate, oxaloacetate, malate-that greatly contribute to the regulation of cell-to-cell communications and metabolic plasticity of brain cells and on some resorbable biopolymers that may reproduce the local microenvironment enriched in particular cell metabolites.
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Affiliation(s)
| | - Frida N. Gilmiyarova
- Department of Fundamental and Clinical Biochemistry with Laboratory Diagnostics, Samara State Medical University, 443099 Samara, Russia
| | - Anton S. Averchuk
- Brain Science Institute, Research Center of Neurology, 125367 Moscow, Russia
| | - Tatiana I. Baranich
- Brain Science Institute, Research Center of Neurology, 125367 Moscow, Russia
| | | | - Maria V. Kukla
- Brain Science Institute, Research Center of Neurology, 125367 Moscow, Russia
| | - Pavel P. Tregub
- Brain Science Institute, Research Center of Neurology, 125367 Moscow, Russia
- Department of Pathophysiology, I.M. Sechenov First Moscow State Medical University, 119991 Moscow, Russia
| | - Alla B. Salmina
- Brain Science Institute, Research Center of Neurology, 125367 Moscow, Russia
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Akcay G, Luttge R. Microenvironments Matter: Advances in Brain-on-Chip. BIOSENSORS 2023; 13:551. [PMID: 37232912 PMCID: PMC10216565 DOI: 10.3390/bios13050551] [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: 03/23/2023] [Revised: 05/04/2023] [Accepted: 05/12/2023] [Indexed: 05/27/2023]
Abstract
To highlight the particular needs with respect to modeling the unique and complex organization of the human brain structure, we reviewed the state-of-the-art in devising brain models with engineered instructive microenvironments. To acquire a better perspective on the brain's working mechanisms, we first summarize the importance of regional stiffness gradients in brain tissue, varying per layer and the cellular diversities of the layers. Through this, one can acquire an understanding of the essential parameters in emulating the brain in vitro. In addition to the brain's organizational architecture, we addressed also how the mechanical properties have an impact on neuronal cell responses. In this respect, advanced in vitro platforms emerged and profoundly changed the methods of brain modeling efforts from the past, mainly focusing on animal or cell line research. The main challenges in imitating features of the brain in a dish are with regard to composition and functionality. In neurobiological research, there are now methods that aim to cope with such challenges by the self-assembly of human-derived pluripotent stem cells (hPSCs), i.e., brainoids. Alternatively, these brainoids can be used stand-alone or in conjunction with Brain-on-Chip (BoC) platform technology, 3D-printed gels, and other types of engineered guidance features. Currently, advanced in vitro methods have made a giant leap forward regarding cost-effectiveness, ease-of-use, and availability. We bring these recent developments together into one review. We believe our conclusions will give a novel perspective towards advancing instructive microenvironments for BoCs and the understanding of the brain's cellular functions either in modeling healthy or diseased states of the brain.
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Affiliation(s)
- Gulden Akcay
- Neuro-Nanoscale Engineering, Department of Mechanical Engineering/Microsystems, Institute of Complex Molecular Systems, Eindhoven University of Technology, 5600 MB Eindhoven, The Netherlands;
| | - Regina Luttge
- Neuro-Nanoscale Engineering, Department of Mechanical Engineering/Microsystems, Institute of Complex Molecular Systems, Eindhoven University of Technology, 5600 MB Eindhoven, The Netherlands;
- Eindhoven Artificial Intelligence Systems Institute, Eindhoven University of Technology, 5600 MB Eindhoven, The Netherlands
- Eindhoven Hendrik Casimir Institute, Eindhoven University of Technology, 5600 MB Eindhoven, The Netherlands
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van Altena PFJ, Accardo A. Micro 3D Printing Elastomeric IP-PDMS Using Two-Photon Polymerisation: A Comparative Analysis of Mechanical and Feature Resolution Properties. Polymers (Basel) 2023; 15:polym15081816. [PMID: 37111964 PMCID: PMC10144803 DOI: 10.3390/polym15081816] [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: 03/08/2023] [Revised: 03/27/2023] [Accepted: 04/02/2023] [Indexed: 04/29/2023] Open
Abstract
The mechanical properties of two-photon-polymerised (2PP) polymers are highly dependent on the employed printing parameters. In particular, the mechanical features of elastomeric polymers, such as IP-PDMS, are important for cell culture studies as they can influence cell mechanobiological responses. Herein, we employed optical-interferometer-based nanoindentation to characterise two-photon-polymerised structures manufactured with varying laser powers, scan speeds, slicing distances, and hatching distances. The minimum reported effective Young's modulus (YM) was 350 kPa, while the maximum one was 17.8 MPa. In addition, we showed that, on average, immersion in water lowered the YM by 5.4%, a very important point as in the context of cell biology applications, the material must be employed within an aqueous environment. We also developed a printing strategy and performed a scanning electron microscopy morphological characterisation to find the smallest achievable feature size and the maximum length of a double-clamped freestanding beam. The maximum reported length of a printed beam was 70 µm with a minimum width of 1.46 ± 0.11 µm and a thickness of 4.49 ± 0.05 µm. The minimum beam width of 1.03 ± 0.02 µm was achieved for a beam length of 50 µm with a height of 3.00 ± 0.06 µm. In conclusion, the reported investigation of micron-scale two-photon-polymerized 3D IP-PDMS structures featuring tuneable mechanical properties paves the way for the use of this material in several cell biology applications, ranging from fundamental mechanobiology to in vitro disease modelling to tissue engineering.
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Affiliation(s)
- Pieter F J van Altena
- Department of Precision and Microsystems Engineering, Faculty of Mechanical, Maritime and Materials Engineering (3mE), Delft University of Technology (TU Delft), Mekelweg 2, 2628 CD Delft, The Netherlands
| | - Angelo Accardo
- Department of Precision and Microsystems Engineering, Faculty of Mechanical, Maritime and Materials Engineering (3mE), Delft University of Technology (TU Delft), Mekelweg 2, 2628 CD Delft, The Netherlands
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