BACKGROUND The aim of this study was to establish and validate a practical method to disperse nanoparticles in physiological solutions for biological in vitro and in vivo studies. RESULTS TiO2 (rutile) dispersions were prepared in distilled water, PBS, or RPMI 1640 cell culture medium. Different ultrasound energies, various dispersion stabilizers (human, bovine, and mouse serum albumin, Tween 80, and mouse serum), various concentrations of stabilizers, and different sequences of preparation steps were applied. The size distribution of dispersed nanoparticles was analyzed by dynamic light scattering and zeta potential was measured using phase analysis light scattering. Nanoparticle size was also verified by transmission electron microscopy. A specific ultrasound energy of 4.2 x 105 kJ/m3 was sufficient to disaggregate TiO2 (rutile) nanoparticles, whereas higher energy input did not further improve size reduction. The optimal sequence was first to sonicate the nanoparticles in water, then to add dispersion stabilizers, and finally to add buffered salt solution to the dispersion. The formation of coarse TiO2 (rutile) agglomerates in PBS or RPMI was prevented by addition of 1.5 mg/ml of human, bovine or mouse serum albumin, or mouse serum. The required concentration of albumin to stabilize the nanoparticle dispersion depended on the concentration of the nanoparticles in the dispersion. TiO2 (rutile) particle dispersions at a concentration lower than 0.2 mg/ml could be stabilized by the addition of 1.5 mg/ml albumin. TiO2 (rutile) particle dispersions prepared by this method were stable for up to at least 1 week. This method was suitable for preparing dispersions without coarse agglomerates (average diameter < 290 nm) from nanosized TiO2 (rutile), ZnO, Ag, SiOx, SWNT, MWNT, and diesel SRM2975 particulate matter. CONCLUSION The optimized dispersion method presented here appears to be effective and practicable for preparing dispersions of nanoparticles in physiological solutions without creating coarse agglomerates.

中文翻译：

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优化的纳米粒子分散体，用于体外和体内生物学研究。

背景技术本研究的目的是建立并验证一种实用的方法来将纳米颗粒分散在生理溶液中，以进行体外和体内生物学研究。结果TiO2（金红石）分散体是在蒸馏水，PBS或RPMI 1640细胞培养基中制备的。应用了不同的超声能量，各种分散稳定剂（人，牛和小鼠血清白蛋白，吐温80和小鼠血清），各种浓度的稳定剂以及不同的制备步骤顺序。通过动态光散射分析分散的纳米颗粒的尺寸分布，并使用相分析光散射测量ζ电势。纳米颗粒的大小也通过透射电子显微镜证实。4.2 x 105 kJ / m3的比超声能量足以分解TiO2（金红石）纳米颗粒，而更高的能量输入并不能进一步提高尺寸。最佳顺序是首先在水中超声处理纳米颗粒，然后添加分散稳定剂，最后向分散液中添加缓冲盐溶液。通过添加1.5 mg / ml的人，牛或小鼠血清白蛋白或小鼠血清，可防止在PBS或RPMI中形成粗TiO2（金红石）附聚物。稳定纳米颗粒分散体所需的白蛋白浓度取决于分散体中纳米颗粒的浓度。浓度低于0.2 mg / ml的TiO2（金红石）颗粒分散液可通过添加1.5 mg / ml白蛋白来稳定。通过这种方法制备的TiO2（金红石）颗粒分散体可稳定至少1周。该方法适用于从纳米级TiO2（金红石），ZnO，Ag，SiOx，SWNT，MWNT和柴油SRM2975颗粒物制备不含粗团块（平均直径<290 nm）的分散体。结论本文介绍的优化分散方法似乎在制备纳米颗粒在生理溶液中的分散液时有效且可行，而不会产生粗大的附聚物。