We report the development of a peptide-based optical nanoprobe specifically tailored for prostate cancer imaging. The imaging probe is comprised of cyclic peptide nanotubes, formed via the aqueous co-assembly of four cyclic D,L-alternating octapeptides. The inherent properties of these cyclic building blocks have been carefully selected to enhance their efficacy in imaging applications, through the addition of a cancer targeting peptide and a fluorescent dye. Comprehensive characterization using scanning electron microscopy (FESEM) and low-voltage transmission electron microscopy (LV-TEM) confirms the formation of nanotubes through co-assembly of the cyclic peptides. The resulting nanotubes show an average diameter of 28 nm. Circular dichroism (CD) spectroscopy validates the formation of stable beta-sheet hydrogen bonding structures at both 20 and 37 °C, ensuring their suitability for biomedical applications. Evaluation of PSMA-binding specificity of the resulting peptide nanotubes is assessed using confocal fluorescence microscopy demonstrating receptor-mediated uptake in prostate cancer cells. We anticipate this strategy will provide the basis for the utilization of co-assembled systems for advancing molecular imaging techniques in prostate cancer and other cancers.

中文翻译：

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用于受体靶向前列腺癌成像的定制肽纳米材料


我们报道了专为前列腺癌成像量身定制的基于肽的光学纳米探针的开发。成像探针由环状肽纳米管组成，通过四个环状 D，L 交替八肽的水共组装形成。这些环状结构单元的固有特性经过精心挑选，通过添加癌症靶向肽和荧光染料来提高它们在成像应用中的功效。使用扫描电子显微镜 （FESEM） 和低压透射电子显微镜 （LV-TEM） 进行全面表征，确认通过环肽的共组装形成纳米管。所得纳米管的平均直径为 28 nm。圆二色性 （CD） 光谱验证了在 20 °C 和 37 °C 下稳定 β-折叠氢键结构的形成，确保其适用于生物医学应用。使用共聚焦荧光显微镜评估所得肽纳米管的 PSMA 结合特异性的评估，证明受体介导的前列腺癌细胞摄取。我们预计该策略将为利用共组装系统推进前列腺癌和其他癌症的分子成像技术奠定基础。