Application Of MOFs And CuSe Electrospun Nanofibers In Wound Repair And Anticance

Electrospinning technology is considered as an effective drug ingredient delivery strategy and has made great progress in drug delivery,tissue engineering,cancer treatment and disease diagnosis.Electrospinning has been recognized as one of the most useful techniques based on its similarity to natural tissue.Electrospinning nanofibers must be able to mimic the extracellular matrix(ECM),provide oxygen and nutrient circulation to tissues,and remove metabolic waste during tissue regeneration.Compared with other methods of preparing composite materials,electrostatic spinning nanofibers have high porosity,high specific surface area and good biocompatibility,which makes them a good carrier of drugs and nanoparticles.However,the conventional electrostatic spinning nanofiber drug loading method has some defects such as low drug loading and fast drug release speed.In addition,electrospinning nanofibers are usually used only in superficial wounds such as skin,and will lose effect in some deep wounds.Based on these problems,we conducted the following studies by combining metal-organic frameworks(MOFs)and CuSe nanoparticles with electrostatic spinning strategies respectively.First,we used two methods("doping method" and "secondary growth method")to prepare gentamicin-loaded ZIF-8 nanoparticles inside and outside the fibers.It is found that the secondary growth method can achieve higher drug loading than doping method,and p H can adjust the release rate of the secondary growth method drug loading fiber.At the same time,the loading amount can be increased and the release speed can be controlled,which can’t be achieved by doping method.The synergistic antibacterial effect appeared in the secondary growth method,and gentamicin loading on ZIF-8 could further promote the antibacterial effect,showing better antibacterial effect than doping method.In the bacterial infection skin experiment,the secondary growth method effectively shortened the wound healing time from 21 to 16 days,showing a faster recovery effect than the doping method.Secondly,we prepared chitosan composite nanofibers embedded with CuSe nanoparticles by green electrospinning method,in which the CuSe nanoparticles have strong absorption in the second near-infrared(NIR-Ⅱ)window.Immediately after a craniotomy to remove the tumor,nanofibers were electrospun and deposited directly onto the resection site with high precision(<6 mm)to achieve rapid hemostasis(<8 s).Moreover,evidenced by the deeper penetration depth of NIR-Ⅱ light(1064 nm)both in the scalp and skull than NIR-Ⅰ light(808 nm),NIR-Ⅱ induced photothermal and photodynamic therapy exhibit efficient superbug-killing rate(>99%)and effectively induce cells apoptosis of residual tumor thereby inhibiting tumor recurrence.Only using the same material,a trilogy of intracranial hemostasis,killing superbug and residual cancer cells is simultaneously achieved.The operation time is short that reduced risk of craniotomy.This electrospinning strategy could combine with craniotomy and minimally invasive surgery,which may provide novel perspectives in clinical operation besides craniotomy.