Gold nanoparticles (AuNPs) have been proposed as useful medical carriers in the field of regenerative medicine. This study aimed to assess the direct conjugation ability of retinoic acid (RA) with AuNPs and to develop a strategy to differentiate the human adipose-derived stromal/stem cells (hADSCs) into neurons using AuNPs-RA. The physical properties of this nanocarrier were characterized using FT-IR, TEM, and FE-SEM. Moreover, the efficiency of RA conjugation on AuNPs was determined at 99% using UV-Vis spectroscopy. According to the MTT assay, an RA concentration of 66 μM caused a 50% inhibition of cell viability and AuNPs were not cytotoxic in concentrations below 5 μg/ml. Real-time PCR and immunocytochemistry proved that AuNPs-RA is able to increase the expression of neuronal marker genes and the number of neuronal protein (GFAP and MAP2)-positive cells, 14 days post-induction of hADSCs. Taken together, these results confirmed that the AuNPs-RA promote the neuronal differentiation of hADSCs.

金纳米粒子 (AuNPs) 已被提议作为再生医学领域中有用的医疗载体。本研究旨在评估视黄酸 (RA) 与 AuNPs 的直接结合能力，并开发一种使用 AuNPs-RA 将人类脂肪来源的基质/干细胞 (hADSCs) 分化为神经元的策略。使用 FT-IR、TEM 和 FE-SEM 表征了这种纳米载体的物理性质。此外，使用 UV-Vis 光谱法测定 RA 结合在 AuNPs 上的效率为 99%。根据 MTT 测定，66 μM 的 RA 浓度导致 50% 的细胞活力抑制，并且 AuNP 在低于 5 μg/ml 的浓度下没有细胞毒性。实时荧光定量 PCR 和免疫细胞化学证明，在 hADSCs 诱导后 14 天，AuNPs-RA 能够增加神经元标记基因的表达和神经元蛋白（GFAP 和 MAP2）阳性细胞的数量。总之，这些结果证实了AuNPs-RA促进hADSCs的神经元分化。