本篇研究藉由觀測兩種不同粒徑：3－5 nm 與 10－30 nm 的 TiO2 奈米粒子，探討 TiO2 奈米粒子在 NIH- 3T3 細胞中的新陳代謝現象。由加入 3－5 nm 與 10－30 nm TiO2 奈米粒子之細胞 1 至 7 天的生長曲線結 果顯示，兩種不同粒徑之奈米粒子皆會對細胞產生抑制生長，其中 3－5 nm TiO2 奈米粒子的抑制效果較 為顯著。利用原子力顯微鏡 (atomic force microscopy, AFM) 對加入 3－5 nm TiO2 奈米粒子的細胞，比較 其 1－7 天細胞膜機械應力的特徵，由細胞核高度變化可發現，細胞核會隨著奈米粒子的加入而膨脹，且 細胞膜黏滯力也會隨著 TiO2 奈米粒子加入的天數而改變。其中細胞核及細胞突觸的黏滯力明顯上升，而 細胞外圍則是下降的現象。研究結果顯示加入 TiO2 奈米粒子會對細胞骨架造成破壞，使細胞結構鬆散， TiO2 奈米粒子會對細胞造成永久性的傷害以及產生細胞病變的現象。

This study compared the effects of 3－5 nm and 10－30 nm TiO2 nanoparticles after exposing to NIH-3T3 cells over a span of 7 days. we observed that TiO2 nanoparticles, of both sizes, are toxic to cells. Both sizes of nanoparticles show cell growth inhibition in which the inhibitory effects of 3－5 nm TiO2 nanoparticles were more significant. Comparative effects of mechanical properties on the cell, and around in which 3－5 nm TiO2 nanoparticles were added, through AFM, showed height variation in the cell nucleus where the nucleus expanded and cell adhesion changed with increasing number of days. The nucleus and cell synapses adhesion were seen to have signifi cantly increased as well, while adhesion force of the cell periphery showed a decline, this showed that cytoskeletal damage caused softening of the cell structure were cause after having being exposed to TiO2 nanoparticles.