Study Of Human Beta-Defense Element-3(HBD-3)/Poly(lactic-co-glycolic Acid)(PLGA) Controlled-release Microspheres Inhibit The Biofilm Formation After Total Knee Arthroplasty

With the development of surgical technique,prosthetic material and biomechanical aspects,artificial joint arthroplasty has become the conventional treatments of serious joint damage,like osteoarthritis,rheumatoid arthritis and femoral head necrosis.Good effects after surgeries and results of long follow-up times make patients and doctors satisfied.However,since the artificial joint arthroplasty to carry out,the infection has been the most serious and the most difficult treatment of complications.In order to prevent and treat infection,clinicians struggle to do the best.Infection after artificial joint arthroplasty not only brings tremendous physical and mental trauma to the patients,the expensive cost of treatment for the infection is huge economic pressure,and the infection also makes medical workers be hit and feel frustration.Therefore,the importance of the prevention of infection after artificial joint arthroplasty is self-evident and vitally important.Objective: To prepare the Human beta defense 3(HBD-3)/poly(lactic-co-glycolic acid)(PLGA)micro-spheres and to investigate the drug release characteristics in vitro.At the same time,to validate the feasibility of Beta-defense element-3(HBD-3)/ poly(lactic-co-glycolic acid)(PLGA)controlled-release microspheres inhibiting biofilm formation after total knee arthroplastyMethod:1.PLGA as a carrier,HBD-3/PLGA controlled-release micro-sphere was prepared by using double emulsion-solvent evaporation method.Using scanning electron microscopy(SEM)to observe its surface morphology.Measuring the drug loading and encapsulation efficiency of HBD-3/PLGA controlled-release micro-sphere.Observing the time of HBD-3/PLGA micro-sphere controlled-release and analyzing the drug release characteristics of micro-sphere.2.In vitro,to observe the size and duration of bacteriostatic zone of HBD-3 in different concentration of solution and HBD-3/PLGA controlled-release microsphere.3.In vivo,to establish the rabbit infective model after artificial joint arthroplasty,the articular cavities of animal models in three groups were inserted HBD to 3 / PLGA sustained release microspheres,pure HBD-3 for positive control and physiological saline for negative control,to observe and detect the result of control and suppression effect on staphylococcus aureus biofilm formation after artificial joint arthroplasty by HBD-3/PLGA sustained microspheres and pure HBD-3.Results1.HBD-3/PLGA controlled-release micro-sphere is smooth surface,uniform distribution and good liquidity,the average particle size of it is 219.49 nm under the Scanning electron microscope(SEM),the drug loading of HBD-3 was(20.67±0.17)% and the encapsulation efficiency was(54.52±1.31)%.It is able to achieve the requirement of the minimum bacteriostatic concentration.2.The cumulative release quantity of HBD-3 was 75.88%,each phase of the release quantity is relatively stable.The cumulative release quantity is(74.12 + 0.43)% on average.3.In vitro,bacteriostatic zone can be seen both in petri dish of pure HBD-3 and HBD-3/PLGA slow-release microspheres.On the tenth day,the bacteriostatic zone of pure HBD-3 solution is 2.66 mm,the bacteriostatic zone of HBD-3/PLGA controlled microsphere is 8.92 mm.4.In vivo,the formation of bacterial biofilm is restrained,which can be observed both in pure HBD-3 and HBD-3/PLGA slow-release microspheres group.Furthermore,the number of bacteria in HBD-3/PLGA controlledmicrospheres group is less under the electron microscope,the time f inhibiting the growth of bacteria and biofilm formation is longer.Conclusion1.HBD-3/PLGA controlled-release micro-sphere has well controlled-release performance in vitro.It can be considered that the purpose of controlled-release antibacterial can be achieved,lay a foundation for subsequent animal antibacterial experiments.2.In vitro,HBD-3/PLGA controlled-release microspheres have the character of slowly releasing,the effect of inhibiting the growth of bacteria and biofilm formation is more obvious and longer,relative to the pure HBD-3 solution.3.In vivo,the result of experiments has established that HBD-3/PLGA sustained-release microspheres can prevent biofilm formation on the surface of artificial joint prosthesis in animal infective model.