Formulation and in-vitro and in-vivo evaluation of a mucoadhesive gel containing freeze dried black raspberries: implications for oral cancer chemoprevention. Pharm Res 2007 Apr;24(4):728-37
Date
03/21/2007Pubmed ID
17372698Pubmed Central ID
PMC2391087DOI
10.1007/s11095-006-9192-1Scopus ID
2-s2.0-33947190100 (requires institutional sign-in at Scopus site) 67 CitationsAbstract
PURPOSE: The purpose of these studies was to formulate mucoadhesive gels containing freeze dried black raspberries (FBR) and to determine optimum parameters for a subset of FBR bioactive compounds including anthocyanin stability, absorption and penetration in-vitro and in-vivo.
MATERIALS AND METHODS: Berry gels were prepared having FBR at 5% and 10% w/w and final pHs ranging from 3.5 to 7.5. A HPLC assay was developed to quantify and determine the stability of the anthocyanins in the gels. A single time-point study was performed to determine anthocyanin uptake when the gels were applied to oral mucosa. Penetration of anthocyanins into human oral tissue explants was determined as a function of gel pH and FBR content. A HPLC-mass spectroscopy assay was utilized to quantify the anthocyanin levels in human oral tissue explants, saliva, and blood.
RESULTS: The stability of anthocyanins in the gel was directly related to gel pH and storage temperature. Maximum stability of anthocyanins was found at lower pH (pH 3.5) and storage temperature (4 degrees C). Anthocyanins contained in mucoadhesive berry gel formulations were readily absorbed into human oral mucosa tissue as evidenced by detectable blood levels within 5 min after gel application. There was a trend for greater penetration of anthocyanins into tissue explants for berry gels with a final pH of 6.5 versus pH 3.5.
CONCLUSIONS: Formulation and characterization of a novel gel formulation for local delivery of chemopreventive compounds to human oral mucosal tissues has been described. The results show anthocyanin stability was dependent upon gel pH and storage temperature and also demonstrate that the gel composition is well-suited for absorption and penetration into the target oral mucosal tissue site.
Author List
Mallery SR, Stoner GD, Larsen PE, Fields HW, Rodrigo KA, Schwartz SJ, Tian Q, Dai J, Mumper RJMESH terms used to index this publication - Major topics in bold
AdhesivenessAnthocyanins
Anticarcinogenic Agents
Chemistry, Pharmaceutical
Chromatography, High Pressure Liquid
Drug Stability
Freeze Drying
Fruit
Gels
Humans
Hydrogen-Ion Concentration
Mass Spectrometry
Mouth Mucosa
Mouth Neoplasms
Mucins
Plant Extracts
Reproducibility of Results
Rosaceae
Saliva
Technology, Pharmaceutical
Temperature
Tissue Culture Techniques
