ABSTRACT
The purpose of this study is to investigate the effects of formulation on the swelling behavior of choline fenofibrate hydrogel matrix tablets and reveal the relation between swelling property and release profile using dynamic image analysis. The volume swelling ratio (SR) and height/width (k) could evaluate the swelling behavior of matrix tablets well. The mount of hydroxypropyl methylcellulose (HPMC) and the ratio between K15M and K4M affected the volume swelling ratio, while PVP didn't. The three factors all impacted k, which was an indicator of the strength of the gel formed by HPMC. The accumulative release ratio and SR, the rate of swelling and the rate of release were compared. The proper model equations were established for the results with an excellent correlation. The results prove that there is a strong relevance between the swelling behavior and release property. This study provides a guideline in the study design for hydrogel matrix tablets.
ABSTRACT
To investigate theological properties of common hydrophilic gel excipients such as Carbopol based on viscosity, the viscosity was determined by rotation method and falling-ball method. Linear regression was made between ln(eta) and concentration, the slope of which was used to explore the relation between viscosity and concentration of different excipients. The viscosity flow active energy (E(eta)) was calculated according to Arrhenius equation and was used to investigate the relation between viscosity and temperature of different excipients. The results showed that viscosities measured by two methods were consistent. Concentration of guargum (GG) and hydroxypropylmethyl cellulose (HPMC) solution had a great influence on the viscosity, k > 5; while concentration of polyvinylpyrrolidone-K30 (PVP-K30) and polyethylene glycol 6000 (PEG6000) exerted a less effect on viscosity, k < 0.2; viscosity flow active energy of different excipients were close, which ranged from 30 to 40 kJ x mol(-1). Therefore, theological properties study could provide the basis for application of excipients and establish a foundation for the research of relation between excipients structure, property and function.