Research On Preparation And Performance Of Antioxidant And Sustained-release Coaxial Nanofiber Membranes Loaded With Curcumin

Curcumin(Cur)is a natural polyphenol drug with excellent pharmacological effects,such as antioxidant,antibacterial,anti-inflammatory and anti-tumor.But Cur has low water solubility,poor stability,and is not easily absorbed by organisms.Nanofiber has a unique physical structure.As a drug carrier,it can play a role in efficient drug loading,encapsulation,and excellent sustained release.Electrospinning is the most commonly used method of nanofiber preparation at present.The coaxial nanofiber with core-shell structure can be spun by simple modification of the electrospinning machine.The operation is simple and convenient,but the influence factors are numerous and complex.In this paper,three groups of antioxidant and sustained-release membranes loaded with Cur were prepared by casting,uniaxial electrospinning and coaxial electrospinning method,using Cur as drug,starch(St)and polyvinyl alcohol(PVA)as substrates,respectively.The sustained-release membranes were characterized and tested,and their Cur release behaviors were analyzed.The differences in structure and performances of Cur-loaded antioxidant sustained-release membranes prepared by different methods were compared.The study found that the preparation methods had no effect on the chemical components of the Cur-loaded membranes.The cast membrane had higher thermal stability due to the tighter blending of the components.On the contrary,the fiber membranes were superior in terms of surface wettability.The microscopic morphology showed that the coaxial fiber membrane had a unique core-shell fiber structure,so it had higher drug loading rate,encapsulation rate,swelling rate and smaller dissolution rate than the other two groups.The coaxial Cur-loaded fiber membrane was superior to the cast membrane and the uniaxial fiber membrane in terms of antioxidant and sustained release properties.The increase of drug loading did not change the chemical components of the coaxial fibers,but the hydrogen bonding between the components was strengthened,and the thermal stability was improved.Through the observation of microscopic morphology,with the increase of Cur content,the diameter of the fiber decreased first and then increased,and the distribution changed from disorder to regular and then disordered.When the Cur content accounted for 9wt% of starch,the overall morphology of the fiber membrane was relatively regular with good surface wettability and swelling property.The water contact angle at 3 min was 33°,and the swelling rate reached 181.47%.Meanwhile,it had excellent antioxidant properties,with the DPPH free radical scavenging rate reached 91.15%.For the coaxial drug-loaded fibers,the shell layer played the role of support and protection.The coaxial Cur-loaded sustained-release membranes were prepared at different shell layer flow rates,and the influence of this factor on the structure and performance of the drug-loaded membrane was further studied.With the increase of the shell velocity,the thickness of the shell layer first increased and then decreased,while the thickness of the core layer did not change significantly.When the flow rate was increased to 0.8 m L/h,the fiber diameter reached the largest,which was 315.38 nm,and the distribution was the most regular.At this time,the coaxial Cur-loaded sustained-release membrane had better surface wettability and mechanical properties.The dissolution rate of the drug-loaded membrane increased with the increase of the flow rate of the shell layer,and the sustained release mode did not change,all of which belongs to the Fick diffusion mode.While,the sustained-release behavior of Cur can be regulated by the shell flow rate.In this study,the differences in structure and properties of antioxidant and sustainedrelease membranes loaded with Cur prepared by casting,uniaxial electrospinning and coaxial electrospinning were compared,which proved that the coaxial Cur-loaded nanofiber membrane had the best comprehensive properties.Coaxial Cur-loaded nanofiber membranes with good mechanical properties,encapsulation properties,antioxidant properties and sustained-release effects were prepared by regulating the drug loading and the flow rate of the shell,which has far-reaching significance in medical fields such as skin wound dressings and in vivo drug implantation.