Dissolution enhancement of tadalafil by liquisolid technique.
This study aimed to enhance the dissolution of tadalafil, a poorly water-soluble drug by applying liquisolid technique. The effects of two critical formulation variables, namely drug concentration (17.5% and 35%, w/w) and excipients ratio (10, 15 and 20) on dissolution rates were investigated. Pre-compression tests, including particle size distribution, flowability determination, Fourier transform infrared (FT-IR), differential scanning calorimetry (DSC), X-ray diffractometry (XRD) and scanning electron microscopy (SEM), were carried out to investigate the mechanism of dissolution enhancement. Tadalafil liquisolid tablets were prepared and their quality control tests, dissolution study, contact angle measurement, Raman mapping, and storage stability test were performed. The results suggested that all the liquisolid tablets exhibited significantly higher dissolution rates than the conventional tablets and pure tadalafil. FT-IR spectrum reflected no drug-excipient interactions. DSC and XRD studies indicated reduction in crystallinity of tadalafil, which was further confirmed by SEM and Raman mapping outcomes. The contact angle measurement demonstrated obvious increase in wetting property. Taken together, the reduction of particle size and crystallinity, and the improvement of wettability were the main mechanisms for the enhanced dissolution rate. No significant changes were observed in drug crystallinity and dissolution behavior after storage based on XRD, SEM and dissolution results.
a School of Pharmacy, Shenyang Pharmaceutical University , Shenyang , China.
Mei
M
Lu
a School of Pharmacy, Shenyang Pharmaceutical University , Shenyang , China.
Haonan
H
Xing
b Department of Basic Pharmaceutical Sciences , School of Pharmacy, Husson University , Bangor , ME , USA.
Tianzhi
T
Yang
a School of Pharmacy, Shenyang Pharmaceutical University , Shenyang , China.
Jiankun
J
Yu
a School of Pharmacy, Shenyang Pharmaceutical University , Shenyang , China.
Zhen
Z
Yang
a School of Pharmacy, Shenyang Pharmaceutical University , Shenyang , China.
Yanping
Y
Sun
a School of Pharmacy, Shenyang Pharmaceutical University , Shenyang , China.
Pingtian
P
Ding
D002152:Calorimetry, Differential Scanning; D004339:Drug Compounding / Q000379:methods; D004355:Drug Stability; D005079:Excipients / Q000737:chemistry*; D010316:Particle Size; D058986:Phosphodiesterase 5 Inhibitors / Q000737:chemistry*; D012995:Solubility; D017550:Spectroscopy, Fourier Transform Infrared; D013607:Tablets; D000068581:Tadalafil / Q000737:chemistry*; D014665:Vasodilator Agents / Q000737:chemistry*; D014867:Water / Q000737:chemistry; D014961:X-Ray Diffraction
D005079:Excipients; D058986:Phosphodiesterase 5 Inhibitors; D013607:Tablets; D014665:Vasodilator Agents; D014867:Water; D000068581:Tadalafil
Dissolution enhancement mechanism; liquisolid tablets; poorly water-soluble drug; tadalafil