The role of the circulatory system, containing the blood and lymphatic vasculatures, within the body, has become increasingly focused on by researchers as dysfunction of either of the systems has been linked to serious complications and disease. Currently, in vivo models are unable to provide the sufficient monitoring and level of manipulation needed to characterize the fluidic dynamics of the microcirculation in blood and lymphatic vessels; thus in vitro models have been pursued as an alternative model. Microfluidic devices have the required properties to provide a physiologically relevant circulatory system model for research as well as the experimental tools to conduct more advanced research analyses of microcirculation flow. In this review paper, the physiological behavior of fluid flow and electrical communication within the endothelial cells of the systems are detailed and discussed to highlight their complexities. Cell co-culturing methods and other relevant organ-on-a-chip devices will be evaluated to demonstrate the feasibility and relevance of the in vitro microfluidic model. Microfluidic systems will be determined as a noteworthy model that can display physiologically relevant flow of the cardiovascular and lymphatic systems, which will enable researchers to investigate the systems' prevalence in diseases and identify potential therapeutics.
Foodborne pathogens, food adulterants, allergens, and toxic chemicals in food can cause major health hazards to humans and animals. Stringent quality control measures at all stages of food processing are required to ensure food safety. There is, therefore, a global need for affordable, reliable, and rapid tests that can be conducted at different process steps and processing sites, spanning the range from the sourcing of food to the end-product acquired by the consumer. Current laboratory-based food quality control tests are well established, but many are not suitable for rapid on-site investigations and are costly. Microfluidic paper analytical devices (μPADs) are a fast-growing field in medical diagnostics that can fill these gaps. In this review, we describe the latest developments in the applications of microfluidic paper analytic device (μPAD) technology in the food safety sector. State-of-the-art μPAD designs and fabrication methods, microfluidic assay principles, and various types of μPAD devices with food-specific applications are discussed. We have identified the prominent research and development trends and future directions for maximizing the value of microfluidic technology in the food sector and have highlighted key areas for improvement. We conclude that the μPAD technology is promising in food safety applications by using novel materials and improved methods to enhance the sensitivity and specificity of the assays, with low cost.
Deformation plays a vital role in the survival of natural organisms. One example is that plants deform themselves to face the sun for sufficient sunlight exposure, which allows them to produce nutrients through photosynthesis. Drawing inspiration from nature, researchers have been exploring the development of 3D deformable materials. However, the traditional approach to manufacturing deformable hydrogels relies on complex technology, which limits their potential applications. In this study, we simulate the stress variations observed in the plant tissue to create a 3D structure from a 2D material. Using UV curing technology, we create a single-layer poly(N-isopropylacrylamide) hydrogel sheet with microchannels that exhibit distinct swelling rates when subjected to stimulation. After a two-step curing process, we produce a poly(N-isopropylacrylamide)-polyethylene glycol diacrylatedouble-layer structure that can be manipulated to change its shape by controlling the light and solvent content. Based on the double-layer structure, we fabricate a dual-response driven bionic mimosa robot that can perform a variety of functions. This soft robot can not only reversibly change its shape but also maintain a specific shape without continuous stimulation. Its capacity for reversible deformation, resulting from internal stress, presents promising application prospects in the biomedical and soft robotics domain. This study delivers an insightful framework for the development of programmable soft materials.