The Investigation Of Bacteriostatic Effect Of Platelet Rich Plasma And Its Composite Silver Ion In Vitro

Background The concept of platelet-rich plasma(PRP)was first proposed by Hood et al in 1993.As the concentration of platelet is more than 3 times that of normal whole blood,a large number of growth factors are released,which promote the repair and regeneration of various tissues.PRP contains a large amount of fibrin,which not only provides a good scaffold for cell growth,but also provides a structural basis for the composite of various cooperative materials.Silver ion is a widely used bacteriostatic material in vitro,which has good bacteriostatic effect and is not easy to produce drug resistance.At present,there are no studies on the combination of the two.Methods PRP and silver ion solution were prepared,and PBS buffer was used as a negative control.The antibacterial effect of PRP,silver ion and their complex on Staphylococcus aureus,Escherichia coli and Pseudomonas aeruginosa in vitro and the duration of antibacterial effect were observed at 37℃.Enzyme-linked immunosorbent assay(ELISA)was used to measure the concentrations of platelet-derived growth factor(PDGF),transforming growth factor-β(TGF-β),epidermal growth factor(EGF)and vascular endothelial growth factor(VEGF)in PRP alone and combined with silver ion.By comparison,to determine the effect of silver ion on the ability of PRP to release growth factors.Results At 37℃,silver ion group and PRP combined with silver ion group showed good antibacterial effects on the growth of Staphylococcus aureus,Escherichia coli and Pseudomonas aeruginosa,and there was no significant difference between the two groups.For Staphylococcus aureus and Escherichia coli,the antibacterial time of the two materials could last up to 36 hours.Against Pseudomonas aeruginosa,the inhibitory effect began to weaken at 24 hours.At 48 hours,both groups completely lost the inhibitory effect on Staphylococcus aureus and Pseudomonas aeruginosa,and still had some inhibitory effect on Escherichia coli.The simple PRP group did not show obvious antibacterial effect on the three bacteria.After PRP combined with silver ions,the concentration of PDGF(315.16±3.19 ng/L),TGF-β(3051.98±19.44 ng/L),EGF(4658.75±62.10 ng/L)and VEGF(1079.00±13.83)were compared with PRP group(316.12±3.08 ng/L,3060.00±18.93 ng/L,4670.61±30.05 ng/L,1081.15±21.63ng/L),there was no significant difference(P > 0.05).Conclusion The antibacterial effect of PRP combined with silver ion was not significantly different from that of silver ion.The antibacterial ability of silver ion was preserved when the two were combined,and silver ion had no effect on the release of growth factors such as PDGF,TGF-β,EGF and VEGF by PRP.