摘要目的 探讨A波段紫外线( ultraviolet A,UVA)和C波段紫外线(ultraviolet C,UVC)对微弧氧化纯钛表面理化性质及体外生物活性的影响,以期探索新的种植体表面处理方法.方法 医用纯钛片微弧氧化(micro-arc oxidation,MAO)处理后,用15W UVA汞灯[λ=(360±20) nm]和15WUVC灭菌灯[λ=(250±20) nm]分别对钛片照射24h.实验分3组:MAO组、MAO+ UVA组、MAO+ UVC组.采用扫描电镜、表面接触角测量仪、X射线能谱仪、X射线衍射仪分析钛片表面理化性能.双金鸡宁酸色度法测定浸泡2、6、24 h后钛片蛋白吸附率,Hoechst细胞核免疫荧光染色实验计算各组材料表面培养MG-63细胞1、2、4h的细胞黏附率,扫描电镜观察细胞形态.结果 3组材料表面形貌、晶相、元素组成均无明显差别；MAO+ UVC组、MAO+ UVA组和MAO组表面接触角分别为(65.34±1.16)°、(44.64±1.28)°和(3.41±0.48)°,3组间差异有统计学意义(P＜0.001).MAO+ UVC组蛋白吸附率在2h达到最大值(48.16±1.24)％,显著高于MAO组[(8.22±2.99)％]和MAO+ UVA组[(5.29±2.27)％,P＜O.001]；培养1、2、4h后MAO+ UVC组表面细胞黏附率[分别为(40.71±4.08)％、(53.72±2.38)％、(70.32±2.85)％]均显著高于相应MAO组和MAO+ UVA组(P ＜0.05)；MAO+ UVC组表面细胞伸展良好,MAO+ UVA组与MAO组无明显差别.结论 UVC照射微弧氧化纯钛表面可提高材料的生物活性,利于细胞的黏附和伸展.

abstractsObjective To study the effects of ultraviolet (UV) light-treatment on the physicochemical properties and bioactivity of micro-arc oxidation(MAO) titanium surfaces in vitro.Methods The pure titanium were prepared using MAO.MAO titanium samples were treated with 15 W bactericidal lamp UVC[λ=(250 ±20) nm]or 15 W mercury lamp[ λ =(360 ±20) nm] for 24 h under ambient conditions.Three sample groups were prepared:MAO,UVA treated after MAO (MAO + UVA),UVC treated after MAO( MAO + UVC ).The surface physicochemical properties were evaluated using scanning electron microscopy( SEM),contact angle measuring device,energy dispersive X-ray spectrometer(EDX),and X-ray diffraction(XRD). Bicinchoninic acid(BCA) based colorimetric detection was used to quantify the percentage of albumin adsorption after 2 h,6 h,and 24 h incubation on the titanium surfaces.The rates of MG-63 cells attached to each group titanium surfaces were calculated by nucleus immunofluorescence using Hoechst 33342 after 1 h,2 h,and 4 h incubation.SEM was used to observe cell morphology on titanium surfaces in each group.Results No obvious differences in surface topography,TiO2 crystal and elemental composition were detected on titanium surfaces with or without UV treatment. Statistically significant difference in contact angles among MAO + UVC group (65.34 ± 1.16)°,MAO + UVA group (44.64 ± 1.28 ) °,and MAO group ( 3.41 ± 0.48 ) ° were found ( P ＜ 0.001 ).The percentage of albumin adsorption reached the plateau after 2 h incubation on MAO + UVC titanium surfaces (48.16 ± 1.24 )％,which was higher than those in MAO [ ( 8.22 ± 2.99 ) ％ ] and MAO + UVA groups [ ( 5.29 ± 2.27 ) ％,P＜0.001].The rates of cells attached to the surfaces of MAO + UVC titanium was greater than that on MAO surfaces and MAO + UVA surfaces after 1 h [ (40.71 ± 4.08 ) ％ ],2 h [ (53.72 ± 2.38 ) ％ ],4 h [ (70.32 ± 2.85 )％ ] incubation (P ＜0.05).The MAO + UVC surfaces remarkably enhanced the spread of MG-63 cells,however,there was no significant difference between the group of MAO and MAO + UVA. Conclusions Pretreatment of micro-arc oxidation titanium with UVC light considerably improved the surface bioactivity to MG-63 cells,which showed an increase in cellular attachment and spread.