Aqueous microdroplets are of significant interest in biological fields, while the employment of water-inoil (w/o) emulsion and lack of spatial control precluded its widespread application. Herein a novel microfluidic ...Aqueous microdroplets are of significant interest in biological fields, while the employment of water-inoil (w/o) emulsion and lack of spatial control precluded its widespread application. Herein a novel microfluidic approach is developed to generate water-in-water (w/w) microdroplets embedded in hydrogel microfibers. Aqueous two phase system (ATPS) is applied to generate w/w droplets, and alginate is introduced to continuous phase to form microfibers, which offers spatial restriction and manipulation possibility to droplets. The size and pattern of aqueous droplets can be precisely controlled, and immobilization within hydrogel fiber facilitates easy manipulation and observation. The microdroplets surrounded by hydrophilic environment can act as a cell-cell interaction model, and their potential for biological and environmental applications are demonstrated by long-term culture of encapsulated cells and water remediation of Bacillus subtilis.展开更多
A water-in-water(W/W)emulsion consists of droplets formed by the spontaneous liquid-liquid separation of two immiscible aqueous phases.The inherent properties of the W/W interfaces,low or ultralowinterfacial tension(...A water-in-water(W/W)emulsion consists of droplets formed by the spontaneous liquid-liquid separation of two immiscible aqueous phases.The inherent properties of the W/W interfaces,low or ultralowinterfacial tension(γ_(W/W)=1-1000μN/m)and a large thickness of several nanometers,beget the poor inherent stability of emulsions.Herein,we report a nanofibril emulsifier having Schiff base reactivity to generate a W/W emulsion.The W/W emulsion has superior stability(stable>6 months)because collagen nanofibrils,acting as a stabilizer of W/W emulsions,can simultaneously satisfy the requirements of sizeandoverall coverage ratio of the phase interfaces.W/Wemulsions having γ_(W/W)∼10μN/m were used as synthetic synovial fluids,showing superior lubrication performance with a coefficient of friction in the range of 0.003-0.011,which has been demonstrated to be suitable for joint lubrication.An intraarticular injection assessment further confirmed this protective effect on articular cartilage in vivo.Our study reveals the mechanism of emulsion stabilization and opens up the possibility of osteoarthritis(OA)treatment using the biolubrication effects of W/W emulsions for lubricated artificial implant surfaces.展开更多
基金financially supported by the National Natural Science Foundation of China (Nos. 81872835, 21621003)Ministry of Science and Technology (Nos. 2017YFC0906902 and 2017ZX09301032)Macao Science and Technology Development Fund (No. 129/2017/A3)
文摘Aqueous microdroplets are of significant interest in biological fields, while the employment of water-inoil (w/o) emulsion and lack of spatial control precluded its widespread application. Herein a novel microfluidic approach is developed to generate water-in-water (w/w) microdroplets embedded in hydrogel microfibers. Aqueous two phase system (ATPS) is applied to generate w/w droplets, and alginate is introduced to continuous phase to form microfibers, which offers spatial restriction and manipulation possibility to droplets. The size and pattern of aqueous droplets can be precisely controlled, and immobilization within hydrogel fiber facilitates easy manipulation and observation. The microdroplets surrounded by hydrophilic environment can act as a cell-cell interaction model, and their potential for biological and environmental applications are demonstrated by long-term culture of encapsulated cells and water remediation of Bacillus subtilis.
基金the National Natural Science Foundation of China(grant nos.22032003,22072073,and 22002072)the Natural Science Foundation of Shandong Province(nos.ZR2018 ZA0547 and ZR2020QB061)+1 种基金Australian Research Council(ARC)DP 190103455the fellowship of China Postdoctoral Science Foundation(no.2020M672043).
文摘A water-in-water(W/W)emulsion consists of droplets formed by the spontaneous liquid-liquid separation of two immiscible aqueous phases.The inherent properties of the W/W interfaces,low or ultralowinterfacial tension(γ_(W/W)=1-1000μN/m)and a large thickness of several nanometers,beget the poor inherent stability of emulsions.Herein,we report a nanofibril emulsifier having Schiff base reactivity to generate a W/W emulsion.The W/W emulsion has superior stability(stable>6 months)because collagen nanofibrils,acting as a stabilizer of W/W emulsions,can simultaneously satisfy the requirements of sizeandoverall coverage ratio of the phase interfaces.W/Wemulsions having γ_(W/W)∼10μN/m were used as synthetic synovial fluids,showing superior lubrication performance with a coefficient of friction in the range of 0.003-0.011,which has been demonstrated to be suitable for joint lubrication.An intraarticular injection assessment further confirmed this protective effect on articular cartilage in vivo.Our study reveals the mechanism of emulsion stabilization and opens up the possibility of osteoarthritis(OA)treatment using the biolubrication effects of W/W emulsions for lubricated artificial implant surfaces.
