Yabutsuka Takeshi, Fukushima Keito, Hiruta Tomoko, Takai Shigeomi, Yao Takeshi
Department of Fundamental Energy Science, Graduate School of Energy Science, Kyoto University, Yoshida-Honmachi, Sakyo-ku, Kyoto 606-8501, Japan.
Department of Fundamental Energy Science, Graduate School of Energy Science, Kyoto University, Yoshida-Honmachi, Sakyo-ku, Kyoto 606-8501, Japan.
Mater Sci Eng C Mater Biol Appl. 2017 Dec 1;81:349-358. doi: 10.1016/j.msec.2017.07.017. Epub 2017 Jul 15.
When bioinert substrates with fine-sized pores are immersed in a simulated body fluid (SBF) and the pH value or the temperature is increased, fine particles of calcium phosphate, which the authors denoted as 'precursor of apatite' (PrA), are formed in the pores. By this method, hydroxyapatite formation ability can be provided to various kinds of bioinert materials. In this study, the authors studied fabrication methods of bioactive PEEK by using the above-mentioned process. First, the fine-sized pores were formed on the surface of the PEEK substrate by HSO treatment. Next, to provide hydrophilic property to the PEEK, the surfaces of the PEEK were treated with O plasma. Finally, PrA were formed in the pores by the above-mentioned process, which is denoted as 'Alkaline SBF' treatment, and the bioactive PEEK was obtained. By immersing in SBF with the physiological condition, hydroxyapatite formation was induced on the whole surface of the substrate within 1day. The formation of PrA directly contributed to hydroxyapatite formation ability. By applying the O plasma treatment, hydroxyapatite formation was uniformly performed on the whole surface of the substrate. The HSO treatment contributed to a considerable enhancement of adhesive strength of the formed hydroxyapatite layer formed in SBF because of the increase of surface areas of the substrate. As a comparative study, the sandblasting method was applied as the pores formation process instead of the HSO treatment. Although hydroxyapatite formation was provided also in this case, however, the adhesion of the formed hydroxyapatite layer to the substrate was not sufficient even if the O plasma treatment was conducted. This result indicates that the fine-sized pores should be formed on the whole surface of the substrate uniformly to achieve high adhesive strength of the hydroxyapatite layer. Therefore, it is considered that the HSO treatment before the O plasma and the 'Alkaline SBF' treatment is an important factor to achieve high adhesive strength of hydroxyapatite layer to the PEEK substrate. This material is expected to be a candidate for next-generation implant materials with high bioactivity.
当具有细孔的生物惰性基材浸入模拟体液（SBF）中且pH值或温度升高时，作者将其称为“磷灰石前体”（PrA）的磷酸钙细颗粒会在孔中形成。通过这种方法，可以赋予各种生物惰性材料形成羟基磷灰石的能力。在本研究中，作者利用上述过程研究了生物活性聚醚醚酮（PEEK）的制备方法。首先，通过HSO处理在PEEK基材表面形成细孔。接下来，为使PEEK具有亲水性，对PEEK表面进行O等离子体处理。最后，通过上述过程（称为“碱性SBF”处理）在孔中形成PrA，从而获得生物活性PEEK。通过将其浸入具有生理条件的SBF中，在1天内可在基材的整个表面诱导形成羟基磷灰石。PrA的形成直接有助于羟基磷灰石的形成能力。通过进行O等离子体处理，可在基材的整个表面均匀地形成羟基磷灰石。由于基材表面积的增加，HSO处理有助于显著提高在SBF中形成的羟基磷灰石层的粘附强度。作为对比研究，采用喷砂法代替HSO处理作为孔形成过程。尽管在这种情况下也能形成羟基磷灰石，但是，即使进行了O等离子体处理，所形成的羟基磷灰石层与基材的粘附力仍不足。该结果表明，应在基材的整个表面均匀形成细孔，以实现羟基磷灰石层的高粘附强度。因此，认为在O等离子体处理和“碱性SBF”处理之前进行HSO处理是实现羟基磷灰石层与PEEK基材高粘附强度的重要因素。这种材料有望成为具有高生物活性的下一代植入材料的候选者。
