A new type of implantable drug delivery devices ( DDD ) with complicated architectures were fubricated by three-dimensional printing technique, employing levofloxacin (LVFX) as a model drug. Processing parameters...A new type of implantable drug delivery devices ( DDD ) with complicated architectures were fubricated by three-dimensional printing technique, employing levofloxacin (LVFX) as a model drug. Processing parameters were optimized in riew of the layer thickness, spucing between printed lines, flow rate of liquid binder and the fast axis speed. The prepared DDD prototype consists of a double-layer structure, of which the upper region is a reservoir system and the lower region is a matrix one. The in vitro release test revealed that LVFX was released in a dual-puse pattern. This DDD may present a new strategy for the prophylaxis and treatment of diseases such as bone infection in the near future.展开更多
The development of personalized healthcare is rapidly growing thanks to the support of low-power electronics,advanced fabrication processes and secured data transmission protocols.Long-acting drug delivery systems abl...The development of personalized healthcare is rapidly growing thanks to the support of low-power electronics,advanced fabrication processes and secured data transmission protocols.Long-acting drug delivery systems able to sustain the release of therapeutics in a controllable manner can provide several advantages in the treatment of chronic diseases.Various systems under development control drug release from an implantable reservoir via concentration driven diffusion through nanofluidic membranes.Given the high drug concentration in the reservoir,an inward osmotic fluid transport occurs across the membrane,which counters the outward diffusion of drugs.The resulting osmotic pressure buildup may be sufficient to cause the failure of implants with associated risks to patients.Confidently assessing the osmotic pressure buildup requires testing in vivo.Here,using metal and polymer AM(additive manufacturing)processes,we designed and developed implantable drug reservoirs with embedded strain sensors to directly measure the osmotic pressure in drug delivery implants in vitro and in vivo.展开更多
Poly(2-hydroxyethyl methacrylate)(PHEMA)and poly(2-hydroxyethyl methacrylate-co-sodium methacrylate) [P(HEMA-co-SMA)]hydrogels with different compositions were prepared to be used as intravaginal rings,and their gelat...Poly(2-hydroxyethyl methacrylate)(PHEMA)and poly(2-hydroxyethyl methacrylate-co-sodium methacrylate) [P(HEMA-co-SMA)]hydrogels with different compositions were prepared to be used as intravaginal rings,and their gelation time,water content,mechanical properties and morphology were investigated.The water content of PHEMA and P(HEMA-co-SMA) hydrogels decreased as the concentration of the monomer and the degree of crosslinking increased,while the water content significantly increased as the content of SMA,the hydrophilic monomer,increased.The increasing of the concentration of the crosslinking agent affected the tensile and flexural properties highly.The presence of a proper small amount of SMA also led the tensile and flexural modulus to move to a higher level.The results showed that P(HEMA-co-SMA) hydrogel with high drug load and good mechanical properties at optimum preparation conditions can be prepared for intravaginal rings to deliver nonhormonal contraceptives.These results may be applied to prepare better intravaginal drug delivery devices.展开更多
Metallomacromolecules are frequently encountered in redox proteins including metal-tanned hide collagen and play crucial roles involving supramolecular properties in biological electron-transfer processes.They are als...Metallomacromolecules are frequently encountered in redox proteins including metal-tanned hide collagen and play crucial roles involving supramolecular properties in biological electron-transfer processes.They are also currently found in non-natural families,such as:metallopolymers,metallodendrimers and metallodendronic polymers.This mini-review discusses the supramolecular redox functions of such nanomaterials developed in our research group.Electron-transfer processes are first examined in mono-,bis-and hexa-nuclear ferrocenes and other electron-reservoir organoiron systems showing the influence of supramolecular and reorganization aspects on their mechanism.Then applications of electron-transfer processes using these same organoiron redox systems in metallomacromolecules and their supramolecular functions are discussed including redox recognition/sensing,catalysis templates,electrocatalysis,redox catalysis,molecular machines,electrochromes,drug delivery device and nanobatteries.展开更多
文摘A new type of implantable drug delivery devices ( DDD ) with complicated architectures were fubricated by three-dimensional printing technique, employing levofloxacin (LVFX) as a model drug. Processing parameters were optimized in riew of the layer thickness, spucing between printed lines, flow rate of liquid binder and the fast axis speed. The prepared DDD prototype consists of a double-layer structure, of which the upper region is a reservoir system and the lower region is a matrix one. The in vitro release test revealed that LVFX was released in a dual-puse pattern. This DDD may present a new strategy for the prophylaxis and treatment of diseases such as bone infection in the near future.
文摘The development of personalized healthcare is rapidly growing thanks to the support of low-power electronics,advanced fabrication processes and secured data transmission protocols.Long-acting drug delivery systems able to sustain the release of therapeutics in a controllable manner can provide several advantages in the treatment of chronic diseases.Various systems under development control drug release from an implantable reservoir via concentration driven diffusion through nanofluidic membranes.Given the high drug concentration in the reservoir,an inward osmotic fluid transport occurs across the membrane,which counters the outward diffusion of drugs.The resulting osmotic pressure buildup may be sufficient to cause the failure of implants with associated risks to patients.Confidently assessing the osmotic pressure buildup requires testing in vivo.Here,using metal and polymer AM(additive manufacturing)processes,we designed and developed implantable drug reservoirs with embedded strain sensors to directly measure the osmotic pressure in drug delivery implants in vitro and in vivo.
文摘Poly(2-hydroxyethyl methacrylate)(PHEMA)and poly(2-hydroxyethyl methacrylate-co-sodium methacrylate) [P(HEMA-co-SMA)]hydrogels with different compositions were prepared to be used as intravaginal rings,and their gelation time,water content,mechanical properties and morphology were investigated.The water content of PHEMA and P(HEMA-co-SMA) hydrogels decreased as the concentration of the monomer and the degree of crosslinking increased,while the water content significantly increased as the content of SMA,the hydrophilic monomer,increased.The increasing of the concentration of the crosslinking agent affected the tensile and flexural properties highly.The presence of a proper small amount of SMA also led the tensile and flexural modulus to move to a higher level.The results showed that P(HEMA-co-SMA) hydrogel with high drug load and good mechanical properties at optimum preparation conditions can be prepared for intravaginal rings to deliver nonhormonal contraceptives.These results may be applied to prepare better intravaginal drug delivery devices.
基金The University of Bordeauxthe Centre National de la Recherche Scientifique(CNRS)+2 种基金the Institut Universitaire de France(IUF)the FP7 European Program“Nanosolution”L’Oreal Research Center.
文摘Metallomacromolecules are frequently encountered in redox proteins including metal-tanned hide collagen and play crucial roles involving supramolecular properties in biological electron-transfer processes.They are also currently found in non-natural families,such as:metallopolymers,metallodendrimers and metallodendronic polymers.This mini-review discusses the supramolecular redox functions of such nanomaterials developed in our research group.Electron-transfer processes are first examined in mono-,bis-and hexa-nuclear ferrocenes and other electron-reservoir organoiron systems showing the influence of supramolecular and reorganization aspects on their mechanism.Then applications of electron-transfer processes using these same organoiron redox systems in metallomacromolecules and their supramolecular functions are discussed including redox recognition/sensing,catalysis templates,electrocatalysis,redox catalysis,molecular machines,electrochromes,drug delivery device and nanobatteries.