Investigation of nicotine release behaviour of tobacco chewing gum in oral cavity by a novel simulated oral dissolution device
For studying the nicotine release behaviours of smokeless tobacco products in the oral cavity, a controllable and reliable method was established and a novel simulated oral dissolution device was designed. Taking the in vivo nicotine dissolution amount of a commercially available tobacco chewing gum (containing 2 mg nicotine per pill) as a reference, the dissolution parameters, including chewing frequency, chewing force and saliva amount, of the simulated device were determined. Then the in vitro nicotine release behaviors of tobacco chewing gums were investigated. The fitting results of in vivo and in vitro dissolution curves indicated that the device simulated the in vivo nicotine dissolution rules of tobacco chewing gums relatively well. The nicotine dissolution rates of several typical tobacco chewing gums with different formula designs and manufacture technologies were compared. The results showed that: (1) The tendency of nicotine dissolution rates of three kinds of chewing gums was first fast and then slow; (2) The nicotine dissolution rates of three kinds of chewing gums reached about 80 % within 15 min; (3) The coating of chewing gum obviously postponed the in vitro dissolution of nicotine at initial chewing stage; (4) The in vitro nicotine dissolution rate of nicotine tartrate salt was much lower than that of ultrafine tobacco powder in previous 8 min, and the former was lower than the latter in the whole chewing process; the slow-release effect of nicotine tartrate salt was obvious. This simulated dissolution method provides a technical support for the manufacture and quality control of tobacco chewing gum.