Chirila T V, Thompson D E, Constable I J
Lions Eye Institute, Nedlands, Australia.
J Biomater Sci Polym Ed. 1992;3(6):481-98. doi: 10.1163/156856292x00457.
Due to their ability to absorb ultraviolet and visible radiation, we have proposed the melanized poly(2-hydroxyethyl methacrylate) hydrogels as biomaterials suitable for the manufacture of soft artificial intraocular lenses. Their biocompatibility has not been evaluated so far. In this study, poly(2-hydroxyethyl methacrylate) containing various amounts of adrenochrome-melanin were synthesized and the cytotoxicity of their aqueous extracts was assessed by using four in vitro testing techniques (trypan blue dye exclusion, inhibition of DNA synthesis, lactate dehydrogenase release, and inhibition of cell growth). Assays were based on incubation with human choroidal fibroblasts. By the first three techniques, no cytotoxicity was found in the extracts. The inhibition of cell growth test showed a slight cellular protein loss, however only in the extracts of polymers with high melanin content. The results suggest that the release of potentially toxic agents from melanized hydrogels into an aqueous medium is not significant. However, when an assay in collagen gel was carried out in the presence of specimens of melanized hydrogels, a toxic reaction was clearly revealed. This can be caused by a delayed release of toxic molecules from melanin, or by some other mechanism. The use of melanin-containing polymers as implant materials becomes questionable and further research is necessary.
由于其吸收紫外线和可见光辐射的能力，我们提出将黑色素化的聚甲基丙烯酸2-羟乙酯水凝胶作为适合制造软性人工晶状体的生物材料。到目前为止，它们的生物相容性尚未得到评估。在本研究中，合成了含有不同量肾上腺色素-黑色素的聚甲基丙烯酸2-羟乙酯，并使用四种体外测试技术（台盼蓝染料排除法、DNA合成抑制法、乳酸脱氢酶释放法和细胞生长抑制法）评估了其水提取物的细胞毒性。实验基于与人脉络膜成纤维细胞的孵育。通过前三种技术，在提取物中未发现细胞毒性。细胞生长抑制试验显示细胞蛋白略有损失，但仅在黑色素含量高的聚合物提取物中出现。结果表明，黑色素化水凝胶中潜在有毒物质向水性介质中的释放并不显著。然而，当在黑色素化水凝胶标本存在的情况下进行胶原凝胶试验时，明显显示出毒性反应。这可能是由于黑色素中有毒分子的延迟释放，或由其他一些机制引起的。使用含黑色素的聚合物作为植入材料变得值得怀疑，需要进一步研究。
