title: [High-performance liquid chromatography for determining celecoxib concentration in hamster tongue tissue after oral local application].
abstract: OBJECTIVE
  To establish a high-performance liquid chromatography (HPLC)-based method for determining celecoxib concentration in the tongue tissue of hamsters.
  
  
  METHODS
  Celecoxib mixed with the matrix (final concentration of 6%) was smeared on the surface of the tongue mucosa of hamsters, and the concentration and absorption rate of celecoxib in the tongue tissue were determined by HPLC at 5, 10, 15, 30, 60, 90, 120 min after the application.
  
  
  RESULTS
  In this system, the retention time of celecoxib was 4.4 min. Celecoxib concentration showed a good linear range within 25-800 microg/L (R2=0.9991, n=6), with the detection limit for celecoxib of 10 g/L (S/N=3). The extraction recoveries and method recoveries for celecoxib were 83.75%-90.01% and 91.98%-99.07%, respectively. The inter-day RSDs were 2.15%, 3.16% and 3.67%, and intra-day RSDs were 3.40%, 4.56% and 4.42%, respectively. The concentration of celecoxib in hamster tongue tissue within the first 120 min ranged from 0.685-/+0.019 microg/g to 3.168-/+0.143 g/g, reaching the peak level at 15 min.
  
  
  CONCLUSIONS
  Celecoxib can be rapidly absorbed through the tongue mucosa to reach a high concentration in the tongue tissue, indicating the possibility of oral COX-2 inhibitors to prevent oral cancer and precancerous lesions.
authors.affiliation: Department of Stomatology, Nanfang Hospital, College of Traditional Chinese Medicine, Southern Medical University, Guangzhou 510515, China. xufang101010 @mail.163.com
authors.forename: Fang
authors.initials: F
authors.lastname: Xu
authors.forename: Wei-zhong
authors.initials: WZ
authors.lastname: Li
authors.forename: Jian-xin
authors.initials: JX
authors.lastname: Diao
mesh_terms: D000818:Animals; D000068579:Celecoxib; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D006224:Cricetinae; D011720:Pyrazoles / Q000032:analysis* / Q000493:pharmacokinetics*; D013449:Sulfonamides / Q000032:analysis* / Q000493:pharmacokinetics*; D014059:Tongue / Q000378:metabolism*
chemical_list: D011720:Pyrazoles; D013449:Sulfonamides; D000068579:Celecoxib