The biocompatibility and anticancer effect of hydroxyapatite nanoparticles (HAPNs) are compelling and promising in cancer nanomedicine. However, the essential role of fetal bovine serum (FBS) in a biological environment possibly determining the state of agglomeration and intracellular fate of HAPNs (length: ~ 60 nm; width: ~ 20 nm) has never been studied. Here, we investigated the importance of FBS in agglomeration and cell response of HAPNs in human osteosarcoma MG-63 cells. Protein adsorption on the surface of HAPNs after mixing with different concentrations of FBS was confirmed using transmission electron microscope (TEM), attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectroscopy, quartz crystal microbalance with dissipation (QCM-D), and thermogravimetric analysis (TG). The adsorption of serum protein improved dispersed state and stabilization of HAPNs, which was evidenced by dynamic light scattering (DLS), inverted microscope, and scanning electron microscope (SEM). More specifically, the agglomerate size of HAPNs in cell culture medium without FBS was above 1400 nm, while the agglomerate size of HAPNs with 10% FBS was decreased to about 200 nm and maintained for at least five days. Meanwhile, serum protein adsorption on HAPN surface enhanced cellular uptake and anticancer efficacy of HAPNs in MG-63 cells.

羟基磷灰石纳米颗粒（HAPNs）的生物相容性和抗癌作用在癌症纳米医学中具有令人信服的前景。但是，从未研究过胎牛血清（FBS）在生物环境中可能决定HAPNs的团聚状态和细胞内命运的重要作用（长度：〜60 nm；宽度：〜20 nm）。在这里，我们调查了FBS在人骨肉瘤MG-63细胞中HAPNs的团聚和细胞应答中的重要性。使用透射电子显微镜（TEM），衰减全反射-傅立叶变换红外（ATR-FTIR）光谱，带耗散的石英晶体微天平（QCM-D）和热重分析（TG）。动态光散射（DLS），倒置显微镜和扫描电子显微镜（SEM）证明了血清蛋白的吸附改善了HAPNs的分散状态和稳定性。更具体地，在没有FBS的细胞培养基中，HAPNs的团聚体尺寸大于1400nm，而具有10％FBS的HAPNs的团聚体尺寸减小至约200nm，并保持至少五天。同时，血清蛋白在HAPN表面的吸附增强了MG-63细胞中HAPNs的细胞摄取和抗癌功​​效。而含10％FBS的HAPNs的团聚体尺寸减小至约200 nm，并保持至少5天。同时，血清蛋白在HAPN表面的吸附增强了MG-63细胞中HAPNs的细胞摄取和抗癌功​​效。而含10％FBS的HAPNs的团聚体尺寸减小至约200 nm，并保持至少5天。同时，血清蛋白在HAPN表面的吸附增强了MG-63细胞中HAPNs的细胞摄取和抗癌功​​效。