小鼠对量子点的透皮吸收和代谢

皮肤是身体的最大器官，能够直接与含纳米材料的防晒霜、化妆品等接触，但是人们对纳米材料的皮肤渗透性却了解不多．本文研究了水溶性硫硒化镉(CdSeS)量子点纳米颗粒的皮肤渗透性和在体内的代谢情况．将雄性ICR鼠背部脱毛，在脱毛部位涂抹直径约为5 nm、发光波长为620 nm的量子点0.32 nmol，然后检测皮肤和心、肝、脾、肺、肾中量子点沉积量随时间的变化情况．荧光显微像显示，量子点能够堆积在皮肤的表皮层中和真皮层的毛囊和腺体中，电感耦合等离子体质谱(inductively coupled plasma-mass spectrometry，ICP-MS)结果表明，透皮吸收的量子点能够沉积在器官中，并且肝和肾中沉积的量子点代谢缓慢，涂抹量子点5天之后，肾脏中残存的镉离子浓度仍超过14 ng/g．这些结果表明，量子点能够被小鼠透皮吸收，而且对肝和肾产生严重影响．

Transdermal Delivery Through in vivo Mouse Skin and Metabolic Path of Quantum Dots

Skin is the largest organ of the body and is a potential route of exposure to sunscreens and cosmetics containing nanoparticles, but the permeability of the skin to these nanoparticles is unknown. In this paper, we studied the transdermal delivery capacity through mouse skin of water-soluble CdSeS quantum dots (QDs) and the deposition of these QDs in the body. QD solution was coated on the dorsal hairless skin of male ICR mice. Fluorescence microscope was used to observe the deposition of QDs in mouse skin and heart, liver, spleen, lung and kidney. Inductively coupled plasma-mass spectrometry (ICP-MS) was used to measure the ¹¹¹Cd concentration to indicate the concentration of QDs in plasma and organs. The fluorescence images show that QDs can penetrate into the dermal layer and deposit in the organs through blood circulation. ICP-MS result indicates that QDs deposit seriously in liver and kidney, and they are difficult to clear. ¹¹¹Cd concentration is still more than 14 ng/g in kidney after 5 days. These results suggest that QDs has in vivo transdermal delivery capacity through mouse skin and is harmful to the liver and kidney.