Researches On Pellets Of Celecoxib

Celecoxib is a selective inhibitor of COX-2,which possesses strong specificity.Meanwhile the efficacy of drugs has been further improved.Celecoxib possesses broad market prospect,which has the ability of treating arthritis and rheumatic arthritis.However,celecoxib has low solubility and nonuniform release during application.Due to drug dissolution is an important part for vivo absorption,therefore,celecoxib also has low bioacailability and unstable absorbing ability.Hence,we designed a new agent in order to improve the bioavailability of celecoxib in vivo.Pellet,which has less influence in intestinal transport and digestive absorption,is characterized by good absorption,higher bioavailability and distinguished abosorption kinetics,therefore,the pellet represented by the multiple-unit drug delivery system,is the main content,has become one of hot spot of research in sustained-controlled preparation by its unique superiority.In this paper,the prescription of quick release and sunstained-controlled release pellets,preparation method and technology were confirmed.In the end,it was determined that celecoxib immediate-release pellets and sustained-release pellets using the HPMC and acrylic resin for coating respectively.The optimum condition of celecoxib immediate-release pellets and sustained-release pellets were determined that 1% lauryl sodium sulfate HCl/H2 O mixed solustion(p H 1.2)with 50 r.m.p.By investigating the concentration of surface active agent,the p H of dissolution and the quick release and the strring rate had influence on sunstained-controlled release pellets.The Higuchi equation was accoed by sustained release pellets of mechanism of releasing,and it belongs to dual-acting mechanism diffusing and eroding,especially the former.In addition,a preliminary research of the stability of celecoxib quick release and sustained-controlled release pellet was conducted.The results showed that celecoxib quick release and sunstained-controlled release pellets were stable in strong illumination,high temperature and humidity.The result of accelerating test was showed that the sample was not evident change in 6 months.By the preliminary research of celecoxib immediate-release and has beendetermined that the pharmacokietic parameters of celecoxib immediate-release pellets:t1/2=6h;Tmax=3h;Cmax=0.7mg/L(100mg/kg),1.4mg/L(200mg/kg),2.8mg/L(400mg/kg),sunstained-controlled release pellet:t1/2=4h;Tmax=8h;Cmax=1.4mg/L(100mg/kg),2.8mg/L(200mg/kg),5.6mg/L(400mg/kg).