Three-dimensional(3D)hydrogel models play a crucial role in tissue engineering for promoting tissue regeneration.A biomimetic microchannel network system in the 3D hydrogel model is necessary for optimal cellular func...Three-dimensional(3D)hydrogel models play a crucial role in tissue engineering for promoting tissue regeneration.A biomimetic microchannel network system in the 3D hydrogel model is necessary for optimal cellular function.This report describes the preparation of a biomimetic hydrogel scaffold with an internal microchannel network,using electrospinning techniques and the sacrificial template method for 3D cell culture.Microchannels and cavities were created within the gelatin methacryloyl(GelMA)hydrogel by sacrificing polyvinyl alcohol(PVA)electrospun fibers(>10µm),resulting in the creation of microvessel-like channels.Mechanical characterizations,swelling properties,and biodegradation analysis were conducted to investigate the feasibility of a biomimetic microchannel network hydrogel scaffold for 3D cell culture applications.Compared to pure GelMA hydrogel,the hydrogel with microchannels promoted cell proliferation,adhesion,and endothelial tube formation.Moreover,the results confirmed that the biomimetic microchannel network scaffold had a major impact on the distribution and arrangement of human umbilical vein endothelial cells(HUVECs)and can enable the formation of artificial microvasculature by the culture of HUVECs and cell media perfusion.展开更多
Vascularization and bone regeneration are two closely related processes during bone reconstruction.A three-dimensional(3D)scaffold with porous architecture provides a suitable microenvironment for vascular growth and ...Vascularization and bone regeneration are two closely related processes during bone reconstruction.A three-dimensional(3D)scaffold with porous architecture provides a suitable microenvironment for vascular growth and bone formation.Here,we present a simple and general strategy to construct a nanofibrous poly(L-lactide)/poly(ε-caprolactone)(PLLA/PCL)scaffold with interconnected perfusable microchannel networks(IPMs)based on 3D printing technology by combining the phase separation and sacrificial template methods.The regular and customizable microchannel patterns within the scaffolds(spacings:0.4 mm,0.5 mm,and 0.6 mm;diameters:0.8 mm,1 mm,and 1.2 mm)were made to investigate the effect of microchannel structure on angiogenesis and osteogenesis.The results of subcutaneous embedding experiment showed that 0.5/0.8-IPMs(spacing/diameter=0.5/0.8)and 0.5/1-IPMs(spacing/diameter=0.5/1)scaffolds exhibited more vascular network formation as compared with other counterparts.After loading with vascular endothelial growth factor(VEGF),VEGF@IPMs-0.5/0.8 scaffold prompted better human umbilical vein endothelial cells(HUVECs)migration and neo-blood vessel formation,as determined by Transwell migration,scratch wound healing,and chorioallantoic membrane(CAM)assays.Furthermore,the microangiography and rat cranial bone defects experiments demonstrated that VEGF@IPMs-0.5/0.8 scaffold exhibited better performance in vascular network formation and new bone formation compared to VEGF@IPMs-0.5/1 scaffold.In summary,our results suggested that the microchannel structure within the scaffolds could be tailored by an adjustable caramel-based template strategy,and the combination of interconnected perfusion microchannel networks and angiogenic factors could significantly enhance vascularization and bone regeneration.展开更多
Fractal networks are widely applied in the field of heat and mass transfer. As one of the important parts of the fractal network, Y-shaped structure definitely has a significant impact on the performance of the whole ...Fractal networks are widely applied in the field of heat and mass transfer. As one of the important parts of the fractal network, Y-shaped structure definitely has a significant impact on the performance of the whole network. In this paper, the analytical relationship between Y-shaped microchannel geometry and its capillary flow time is established through theoretical analysis with mass continuity equation and Navier-Stokes(N-S) equations.The result reveals that the capillary flow time increases with the increase of the topology length and bifurcation angle of the Y-shaped microchannel, but decreases with the increase of the channel width.展开更多
基金supported by the National Natural Science Foundation of China(No.31870934)the Natural Science Foundation for Young Scientists of Shanxi Province(No.202103021223100),China.
文摘Three-dimensional(3D)hydrogel models play a crucial role in tissue engineering for promoting tissue regeneration.A biomimetic microchannel network system in the 3D hydrogel model is necessary for optimal cellular function.This report describes the preparation of a biomimetic hydrogel scaffold with an internal microchannel network,using electrospinning techniques and the sacrificial template method for 3D cell culture.Microchannels and cavities were created within the gelatin methacryloyl(GelMA)hydrogel by sacrificing polyvinyl alcohol(PVA)electrospun fibers(>10µm),resulting in the creation of microvessel-like channels.Mechanical characterizations,swelling properties,and biodegradation analysis were conducted to investigate the feasibility of a biomimetic microchannel network hydrogel scaffold for 3D cell culture applications.Compared to pure GelMA hydrogel,the hydrogel with microchannels promoted cell proliferation,adhesion,and endothelial tube formation.Moreover,the results confirmed that the biomimetic microchannel network scaffold had a major impact on the distribution and arrangement of human umbilical vein endothelial cells(HUVECs)and can enable the formation of artificial microvasculature by the culture of HUVECs and cell media perfusion.
基金This work was financially supported by the National Key Research and Development Program of China(2018YFB1105602)National Natural Science Foundation of China(32071350,31771048,81702124)+1 种基金Fundamental Research Funds for the Central Universities(2232018A3-07,2232019A3-06)International Cooperation Fund of the Science and Technology Commission of Shanghai Municipality(19440741600).
文摘Vascularization and bone regeneration are two closely related processes during bone reconstruction.A three-dimensional(3D)scaffold with porous architecture provides a suitable microenvironment for vascular growth and bone formation.Here,we present a simple and general strategy to construct a nanofibrous poly(L-lactide)/poly(ε-caprolactone)(PLLA/PCL)scaffold with interconnected perfusable microchannel networks(IPMs)based on 3D printing technology by combining the phase separation and sacrificial template methods.The regular and customizable microchannel patterns within the scaffolds(spacings:0.4 mm,0.5 mm,and 0.6 mm;diameters:0.8 mm,1 mm,and 1.2 mm)were made to investigate the effect of microchannel structure on angiogenesis and osteogenesis.The results of subcutaneous embedding experiment showed that 0.5/0.8-IPMs(spacing/diameter=0.5/0.8)and 0.5/1-IPMs(spacing/diameter=0.5/1)scaffolds exhibited more vascular network formation as compared with other counterparts.After loading with vascular endothelial growth factor(VEGF),VEGF@IPMs-0.5/0.8 scaffold prompted better human umbilical vein endothelial cells(HUVECs)migration and neo-blood vessel formation,as determined by Transwell migration,scratch wound healing,and chorioallantoic membrane(CAM)assays.Furthermore,the microangiography and rat cranial bone defects experiments demonstrated that VEGF@IPMs-0.5/0.8 scaffold exhibited better performance in vascular network formation and new bone formation compared to VEGF@IPMs-0.5/1 scaffold.In summary,our results suggested that the microchannel structure within the scaffolds could be tailored by an adjustable caramel-based template strategy,and the combination of interconnected perfusion microchannel networks and angiogenic factors could significantly enhance vascularization and bone regeneration.
基金the National Natural Science Foundation of China(No.51375169)
文摘Fractal networks are widely applied in the field of heat and mass transfer. As one of the important parts of the fractal network, Y-shaped structure definitely has a significant impact on the performance of the whole network. In this paper, the analytical relationship between Y-shaped microchannel geometry and its capillary flow time is established through theoretical analysis with mass continuity equation and Navier-Stokes(N-S) equations.The result reveals that the capillary flow time increases with the increase of the topology length and bifurcation angle of the Y-shaped microchannel, but decreases with the increase of the channel width.