Organ-on-A-chip (OoAC) devices are functional, miniature in vitro structures that use several cell types and extracellular matrix to replicate the physiology of an organ in vivo while preserving the mechanical and chemical characteristics of the surrounding microenvironments, this technology overcomes the drawbacks of traditional 2D cultures by integrating microfluidic technologies to replicate the intricate physiological conditions of human organs. New avenues for comprehending cellular responses, drug screening, disease modelling, and cell-cell interactions have been made possible by this progression.
Effectiveness of Organ-on-a-chips and Some Requirements
Microchips’ effectiveness, reliability and appropriateness for different biomedical applications depend on their design and production. Hence, it is important to consider certain parameters like the biological model, channel shape and number. Additionally, the selection of appropriate materials compatible with cells and fabrication methods enhances the effectiveness of chips for particular applications with minimalization of weaknesses of such systems. Organ-on-a-chip studies are one of the most active subfields of tissue engineering that has emerged in the last ten years. To create organ-on-chip models, an integrated, multidisciplinary approach that incorporates disciplines like microfabrication, microfluidics, biomaterials, stem cell science, pharmacology/toxicology, and medicine, is required.
Several global initiatives have led to the development of many new approaches and ideas, some of which have been incorporated into for-profit products effectively.
Tissue Engineering
Definition and History
Participants in the first NSF-sponsored meeting in 1988 defined tissue engineering as the “application of the principles and methods of engineering and life sciences toward a fundamental understanding of structure-function relationship in normal and pathological mammalian tissues and the development of biological substitutes for the repair or regeneration of tissue or organ function.” In 1993, Langer and Vacanti summarized the early developments of tissue engineering as “an interdisciplinary field that applies the principles of engineering and life sciences toward the development of biological substitutes that restore, maintain, or improve tissue or organ function.”
Importance of Tissue Engineering
Tissue engineering has drawn interest recently as a potential alternative to organ or tissue transplantation. With this technology, ex vivo perfusion devices or the implantation of a biological substitute that has been designed can be used to treat tissue loss or organ failure. After being implanted, the tissue-engineered products may integrate and produce the intended functional tissue (e.g., chondrocytes embedded in a matrix carrier) or they may be completely functioning at the time of therapy (e.g., liver assist devices, encapsulated islets). Biomaterials can occasionally be altered to improve the migration and adhesion of particular cell populations that replace or repair damaged tissue.
Microfluidics and Microfluidic Chips
Microfluidics is the study of the manipulation of fluid on the scale of tens of micrometre channels. Applications of microfluidics can be found in areas as diverse as biological analysis, chemical synthesis, information technology and optics. Several scientific studies and the creation of tools for moving and modifying fluids as well as patterning surfaces have been spurred by the capacity to produce structures and patterns on micron and lower length scales. Therefore, design, manipulation, and control of length scales that are getting closer to the molecular are the focus of the engineering paradigm. These fluid-related studies, which are often categorized under the umbrella of microfluidics, have reignited interest in low Reynolds number flows, a traditional field of fluid dynamics.
Microfluidic Chip Technology
The microfluidic chip consists of a series of grooves or microchannels etched on various materials, including silicon, glass, and polymers like polymethylmethacrylate (PMMA), polydimethylsiloxane (PDMS), and polymethylmethacrylate. For the intended outcomes, the microchannels that make up the microfluidic chip are connected. As an interface between the macro and micro worlds, the arrangement of microchannels that are trapped inside the microfluidic chip is connected to the outside by inputs and outputs that pass through the chip. The microfluidic chip uses a pump and a chip to help identify the microfluid’s change in behaviour. Microfluidic channels within the chip allow for fluid processing, including blending and physicochemical reactions.
The microfluidic chip has many advantages, such as requiring less time and reagents and being able to do multiple tasks at once. As the surface area grows, the chip’s microscopic size accelerates the reaction. It is used in a variety of biomedical applications, including pregnancy, glucose estimation, PCR activity, tissue engineering, food safety sensing, peptide analysis, and medical diagnostics. The design of several microfluidic chips and their potential uses in biomedicine have been covered in this study.
The Future of Organ-on-a-chips
Organ-on-a-chip technology is a cutting-edge, multidisciplinary method that mimics in vivo pathology and physiology for precision medicine, drug screening, and in vitro disease modelling. This technology provides a more precise and morally sound way to study human health by mimicking human organ-level functioning in a controlled microenvironment, bridging the gap between animal research and clinical trials. More effective and dependable research results are made possible by its smooth integration into the drug development pipeline, which includes preclinical testing, early drug discovery, and the translation of novel therapeutics.
Developments in Research
Recent developments in stem cell research, tissue engineering, and microfabrication methods have greatly expanded the potential of organ-on-a-chip platforms. The range of biomedical applications has been increased by combining biological advancements like patient-specific induced pluripotent stem cells and organoids with innovative engineering techniques like robotic handling, 3D printing, and in situ multisensors. By making it easier to create patient-specific models, these advancements promote customized treatment and enhance the ability to predict therapeutic responses.[9]
High-throughput sensing technologies in conjunction with organ-on-a-chip systems provide a potent substitute for static microphysiological systems and traditional 2D cell cultures. These platforms successfully imitate important structural, physiological, and functional features of tissues and organoids, enabling more realistic modelling of both healthy and pathological states, even though they do not recreate entire organ systems. Real-time monitoring of biomarker and metabolite release in response to physicochemical stress is made possible by the use of integrated biosensors, which offer vital information on the course of disease and the effectiveness of medications.
Closing Remarks on Organ-on-a-chip Technologies
The potential of organ-on-a-chip technology to expedite medication development and enhance personalized medicine programs is shown in the increasing adoption of this technology by biotechnology and pharmaceutical businesses. The combination of state-of-the-art engineering and biological developments will spur more developments as the sector develops, confirming organ-on-a-chip technology as a game-changing instrument for clinical and scientific research.
References
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Cao, U. M. N., Zhang, Y., Chen, J., Sayson, D., Pillai, S., & Tran, S. D. (2023). Microfluidic Organ-on-A-Chip: A guide to biomaterial choice and fabrication. International Journal of Molecular Sciences, 24(4), 3232. https://doi.org/10.3390/ijms24043232
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