2022, Vol. 26 ›› Issue (21): 3351-3356

Characterization of chitosan-modified polyetheretherketone and its effect on MC3T3-E1 cell adhesion and proliferation

Feng Le, Qiu Peng, Liu Min, Zhou Hui   

Abstract: BACKGROUND: The biological inert surface of polyetheretherketone limits its medical application, so how to improve the biological activity of polyetheretherketone needs to be solved urgently.
OBJECTIVE: To analyze the surface characteristics of polyetheretherketone modified by chitosan bioactive coating and its effect on the adhesion and proliferation of MC3T3-E1 cells.
METHODS: Disc-shaped polyetheretherketone material was obtained and treated with NaBH4, 3-aminopropyltriethoxysilane, glutaraldehyde aqueous solution, and chitosan solution to form polyetheretherketone modified with chitosan bioactive coating. X-ray photoelectron spectroscopy, scanning electron microscope, atomic force microscope, and automatic contact angle measurement instrument were used to observe the surface characteristics of chemically treated polyetheretherketone. MC3T3-E1 cells were seeded on the surface of polyetheretherketone and chitosan-modified polyetheretherketone separately, and the proliferation and adhesion of the cells were observed.
RESULTS AND CONCLUSION: (1) X-ray photoelectron spectroscopy showed that the polyetheretherketone material only contained C and O elements. The chitosan modified polyetheretherketone material contained C, O, N, and Si elements. The contact angle on the surface of chitosan modified polyetheretherketone material was smaller than that of the polyetheretherketone material (P < 0.05). (2) Under the scanning electron microscope, the surface of the polyetheretherketone material had obvious groove-like undulations, and the surface of the chitosan-modified polyetheretherketone material had chitosan molecule. The size was 1.0-2.0 μm. Atomic force microscope exhibited that there were many tiny pits on the surface of the polyetheretherketone material, and the size was about 0.1 μm. The pits on the surface of the chitosan-modified polyetheretherketone material increased; the size was 0.2-0.5 μm, and the surface roughness was greater than that of the polyetheretherketone material. (3) Under an inverted microscope, the number of cells on the surface of the chitosan-modified polyetheretherketone material was more than that of the polyetheretherketone material (P < 0.05 ). Under a laser confocal microscope, the cells adhered to the surface of the polyetheretherketone material had poor stretchability, fewer pseudopods, and inconspicuous actin microfilaments. The extensibility of cells adhered to the surface of the chitosan-modified polyetheretherketone material was better; the pseudopodia were more; the actin microfilament was more and obvious. (4) CCK-8 experiment showed that the cell proliferation on the surface of the chitosan-modified polyetheretherketone material was faster than that of the polyetheretherketone material (P < 0.05). (5) These results confirm that chitosan surface modification increases surface roughness and wettability of polyetheretherketone, promotes adhesion and proliferation of MC3T3-E1 cells on the surface of the material.
Key words: polyetheretherketone, chitosan, biomaterials, surface modification, biosafety, osteoblast, implant, cell proliferation, cell adhesion