Smoke a nanotube?

Nanotubes for instant nicotine deliveryChemPort.Ru based on the materials of the Royal Society of Chemistry: Nicotine hit at the flick of a switch with new nanotube patch
Researchers from the USA have demonstrated that a membrane with carbon nanotubes embedded in it can be used to instantly deliver a small portion of nicotine into the body.

This distinguishes the new dosing system in a favorable light from methods based on continuous diffusion through the skin of the drug from the nicotine patch used by people trying to quit smoking.

The inventors of the new system suggest that their proposed approach will allow nicotine to be delivered to the body at the very moment when it is most needed by a person trying to get rid of an addiction. Thus, an approach based on one-time mini-injections will not require the quitter to change his usual behavior, psychologically facilitating withdrawal from addiction.

Researchers from the Bruce Hinds group from the University of Kentucky (Lexinton) introduced multi-walled carbon nanotubes into a composite material, after which they turned the composite into ultrathin membranes using microtomination. Then, using electrochemical methods, diazonium derivatives were grafted to the ends of carbon nanotubes, the decomposition of which led to the formation of a homogeneous layer of polybenzoic acid. This layer, in turn, was introduced into reaction with dye molecules containing negatively charged sulfonate groups. In such a functionalized form, the membrane can behave like an electrode.

The researchers then placed a nicotine reservoir on the surface of the membrane, which contained a second electrode. Hince notes that the application of a negative charge to the lower surface of the membrane and a positive charge to a solution containing nicotine, the movement of positively charged ions to the nanotubes was observed. The movement of cations led to the fact that neutral molecules were also involved in this movement (this phenomenon is called "electroosmosis"). At a pH value of 8, 50% of nicotine exists in the form of a cation, which further facilitates the movement of the drug through the membrane.

Hinds notes that pumping nicotine requires not too powerful an energy source – no more than a battery for a watch. The inner walls of carbon nanotubes provide low "molecular friction" – nicotine molecules passing through carbon nanotubes experience virtually no resistance, which, according to the researchers, may be another reason for the high efficiency of the system.

Hinds states that laboratory studies have shown that a miniature system effectively delivers a dose of nicotine for a short period of time, while other systems that inject small doses of drugs currently on the market are cumbersome. The researchers suggest that the new system may be useful for people seeking to get rid of nicotine addiction. However, currently the system remains experimental, and its immediate commercialization is not planned.

Portal "Eternal youth" http://vechnayamolodost.ru21.06.2010