Considerable efforts have been devoted to the modification of carbon nanotubes (CNTs) because of their structure dependent mechanical and electronic properties. The length and functionality of the modified CNTs are very important characteristics for biomedical applications. Single-Walled Carbon Nanotubes can be succesfully cut with relatively homogeneous sizes using a planetary mill. Mechanochemistry involves the transformation of mechanical energy into the driving force for the chemical modification of solid structures, avoiding the use of strong acid conditions. The optimized conditions produce highly dispersible SWNTs that can be efficiently functionalized in a variety of synthetic ways.