The need to continuously separate multiple microparticles is required for the recent development of lab-on-chip technology. Dielectrophoresis（DEP）-based separation device is extensively used in kinds of microfluidic...The need to continuously separate multiple microparticles is required for the recent development of lab-on-chip technology. Dielectrophoresis（DEP）-based separation device is extensively used in kinds of microfluidic applications. However, such conventional DEP-based device is relatively complicated and difficult for fabrication. A concise microfluidic device is presented for effective continuous separation of multiple size particle mixtures. A pair of acupuncture needle electrodes are creatively employed and embedded in a PDMS（poly-dimethylsiloxane） hurdle for generating non-uniform electric field thereby achieving a continuous DEP separation. The separation mechanism is that the incoming particle samples with different sizes experience different negative DEP（n DEP） forces and then they can be transported into different downstream outlets. The DEP characterizations of particles are calculated, and their trajectories are numerically predicted by considering the combined action of the incoming laminar flow and the n DEP force field for guiding the separation experiments. The device performance is verified by successfully separating a three-sized particle mixture, including polystyrene microspheres with diameters of 3 μm, 10 μm and 25 μm. The separation purity is below 70% when the flow rate ratio is less than 3.5 or more than 5.1, while the separation purity can be up to more than 90% when the flow rate ratio is between 3.5 and 5.1 and meanwhile ensure the voltage output falls in between 120 V and 150 V. Such simple DEP-based separation device has extensive applications in future microfluidic systems.展开更多
Cell therapy is a promising strategy for acute liver failure(ALF),while its therapeutic efficacy is often limited by cell loss and poor arrangement.Here,inspired by liver microunits,we propose a novel spatially ordere...Cell therapy is a promising strategy for acute liver failure(ALF),while its therapeutic efficacy is often limited by cell loss and poor arrangement.Here,inspired by liver microunits,we propose a novel spatially ordered multicellular lobules for the ALF treatment by using a microfluidic continuous spinning technology.The microfluidics with multiple microchannels was constructed by assembling parallel capillaries.Sodium alginate(Alg)solution encapsulating human umbilical vein endothelial cells(HUVECs),hepatocytes,and mesenchymal stem cells(MSCs)are introduced into the middle channel and the 6 parallel outer channels of the microfluidics,respectively.Simultaneously,Ca^(2+)-loaded solutions are pumped through the innermost and outermost channels,forming a hollow microfiber with hepatocytes and MSCs alternately surrounding the HUVECs.These microfibers could highly resemble the cord-like structure of liver lobules,bringing about outstanding liver-like functions.We have demonstrated that in ALF rats,our biomimetic lobules can effectively suppress excessive inflammatory responses,decrease cell necrosis,and promote regenerative pathways,leading to satisfied therapeutic efficacy.These findings underscore the potential of spatially ordered multicellular microfibers in treating related diseases and improving traditional clinical methods.展开更多
基金Supported by National Natural Science Foundation of China(Grant No.51305106)Fundamental Research Funds for the Central Universities,China(Grant Nos.HIT.NSRIF.2014058,HIT.IBRSEM.201319)Open Foundation of State Key Laboratory of Fluid Power Transmission and Control,China(GZKF-201402)
文摘The need to continuously separate multiple microparticles is required for the recent development of lab-on-chip technology. Dielectrophoresis（DEP）-based separation device is extensively used in kinds of microfluidic applications. However, such conventional DEP-based device is relatively complicated and difficult for fabrication. A concise microfluidic device is presented for effective continuous separation of multiple size particle mixtures. A pair of acupuncture needle electrodes are creatively employed and embedded in a PDMS（poly-dimethylsiloxane） hurdle for generating non-uniform electric field thereby achieving a continuous DEP separation. The separation mechanism is that the incoming particle samples with different sizes experience different negative DEP（n DEP） forces and then they can be transported into different downstream outlets. The DEP characterizations of particles are calculated, and their trajectories are numerically predicted by considering the combined action of the incoming laminar flow and the n DEP force field for guiding the separation experiments. The device performance is verified by successfully separating a three-sized particle mixture, including polystyrene microspheres with diameters of 3 μm, 10 μm and 25 μm. The separation purity is below 70% when the flow rate ratio is less than 3.5 or more than 5.1, while the separation purity can be up to more than 90% when the flow rate ratio is between 3.5 and 5.1 and meanwhile ensure the voltage output falls in between 120 V and 150 V. Such simple DEP-based separation device has extensive applications in future microfluidic systems.
基金supported by the National Natural Science Foundation of China(82270646,T2225003,and 82100664)the National Key Research and Development Program of China(2022YFA1105300)+5 种基金the Jiangsu Provincial Science and Technology Special Fund for Outstanding Young Scholars(BK20230051)Special Funding of Jiangsu Province Concept Validation Center Nanjing Drum Tower Hospital(2024-GNYZ-ZD-03)the Nanjing Health Science and Technology Development Project for Distinguished Young Scholars(JQX22003)the Clinical Trials from Nanjing Drum Tower Hospital(2022-LCYJ-ZD-01)the Guangdong Basic and Applied Basic Research Foundation(2021B1515120054)the Joint Fund of Henan Province Science and Technology R&D Program(Project No.225200810021).
文摘Cell therapy is a promising strategy for acute liver failure(ALF),while its therapeutic efficacy is often limited by cell loss and poor arrangement.Here,inspired by liver microunits,we propose a novel spatially ordered multicellular lobules for the ALF treatment by using a microfluidic continuous spinning technology.The microfluidics with multiple microchannels was constructed by assembling parallel capillaries.Sodium alginate(Alg)solution encapsulating human umbilical vein endothelial cells(HUVECs),hepatocytes,and mesenchymal stem cells(MSCs)are introduced into the middle channel and the 6 parallel outer channels of the microfluidics,respectively.Simultaneously,Ca^(2+)-loaded solutions are pumped through the innermost and outermost channels,forming a hollow microfiber with hepatocytes and MSCs alternately surrounding the HUVECs.These microfibers could highly resemble the cord-like structure of liver lobules,bringing about outstanding liver-like functions.We have demonstrated that in ALF rats,our biomimetic lobules can effectively suppress excessive inflammatory responses,decrease cell necrosis,and promote regenerative pathways,leading to satisfied therapeutic efficacy.These findings underscore the potential of spatially ordered multicellular microfibers in treating related diseases and improving traditional clinical methods.
