OBJECTIVE: To study the preparation of Huperzine-A double-layer sustained release tablets and their in vitro release characteristics.METHODS: With HPMC K4M as matrix and lactose as diluting agent for the sustained release layer,and with starch-calcium carbonate as diluting agent and sodium carboxymethyl starch as disintegrating agent for the fast release layer to prepare the double-layer tablets by compression,with the release rate of the compressed tablets determined by HPLC.RESULTS: The fast release layer of the prepared Huperzine-A double-layer tablets disintegrated within 1～2 min and appeared as fine powder,meeting the requirement;the release curve of the sustained release layer of the tablets was in line with Higuchi equation and maintained a sustained release of 12 hours.CONCLUSION: The prepared Huperzine-A double-layer tables achieved the goal of both immediate release and sustained release.

To study on the four natures (cold, hot, warm, and cool) of Chinese materia medica (CMM) is a central and knotty issue in the field of traditional Chinese medicine (TCM) and no substantial progress has been made so far, which is an obstacle in the course for the modernization of TCM. By application of apoptosis for researching the four natures of CMM, the relationship between the biological efficiency and apoptosis has been explained in a qualitative and quantitative way. A pattern recognition system for the four natures of CMM has been set up in a molecular level. That is a breakthrough to measure the four natures of CMM. Based on the abundant literatures at home and abroad, and the study done as well, the original thinking and fresh viewpoint on the orientation and development for the four natures of CMM have been put forward and then the explanation and prospective analysis on them have been carried out.