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Updated: Nov 1, 2025

Anionic Polymerization of an Amphiphilic Copolymer for Preparation of Block Copolymer Micelles Stabilized by π-π Stacking Interactions
Published on: October 10, 2016
The effect of some acrylic polymers on dissolution of celecoxib solid dispersion formulations
Maryam Maghsoodi1, Ali Nokhodchi2, Hadi Pourasghari Azar1
1Faculty of Pharmacy and Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.
Objective:
The purpose of the present study was firstly to identify the effectiveness of Eudragit® polymers (Eudragit® RL, RS, L100-55, L100, S100 and E100) in inhibition of celecoxib precipitation from buffer solutions (pH = 6.8). Furthermore, the influence of Eudragit® polymers on non-sink dissolution behavior of celecoxib from solid dispersions was investigated.
Methods:
Solid dispersions were prepared by the rotary evaporation method. In vitro dissolution studies, FT-IR and differential scanning calorimetry were employed to characterize the formulations.
Results:
The results revealed that Eudragit® E100, L100 and S100 inhibited precipitation of celecoxib efficiently. It is understood that crystallization during the dissolution of solid dispersions could happen through crystallization from solid matrix following contact with the dissolution medium or from the supersaturated solution produced following dissolution. The supersaturated drug concentrations attained from the dissolution of Eudragit®-celecoxib solid dispersions were almost similar, suggesting that crystallization from solid matrix did not occur readily. However, only solid dispersions containing efficient crystallization inhibitor polymers were able to maintain the supersaturated solution up to the end of the dissolution run.
Conclusion:
Results revealed that the principal mechanism of attaining supersaturated solution of celecoxib from solid dispersions was related to crystallization inhibition from solution not from solid matrix.
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