A metal tip with a large surface area

The objective of this patent is to achieve a new class of drug detected and released needle with large surface to absorbs and release the indicator or drug. The approach is to explore the tungsten and aluminum novel sub-micron or nano needle. This approach is expect to provide both tiny needle but large needle surface area to significantly boost the achievable the sensitively of drug detected and released. New electrochemical processes including electro-polished, electro-etched, and anodization are introduced to assistance a tiny needle and nanotube film under ambient conditions, thereby enabling low-cost and mass production of the needle.