Search Our Scientific Publications & Authors

Eur J Pharm Biopharm 2022 Aug 3. Epub 2022 Aug 3.

School of Pharmacy, Nanjing University of Chinese Medicine, Nanjing 210023, PR China; Jiangsu Provincial TCM Engineering Technology Research Center of High Efficient Drug Delivery System (DDS), Nanjing 210023, PR China. Electronic address:

Co-amorphous strategy has been extensively investigated to improve the dissolution of hydrophobic drugs. Here, epigallocatechin-3-gallate (EGCG) was exploited as a co-former in co-amorphous systems based on its unique structure including phenyl rings, phenolic hydroxyl groups and the galloyl moiety. Two model BCS class II drugs, simvastatin (SIM) and nifedipine (NIF), were selected to be co-amorphized with EGCG. Read More

Int J Pharm 2022 Mar 15;615:121471. Epub 2022 Jan 15.

Department of Pharmaceutics and Drug Delivery, School of Pharmacy, The University of Mississippi, University, MS 38677, USA; Pii Center for Pharmaceutical Technology, The University of Mississippi, University, MS 38677, USA. Electronic address:

Nucleation inhibition and maintenance of drug supersaturation over a prolonged period are desirable for improving oral absorption of amorphous solid dispersions. The present study investigates the impact of binary and ternary amorphous solid dispersions on the supersaturation kinetics of nifedipine using the polymers hydroxypropylmethylcellulose acetate succinate (HPMCAS) LG, and HG, Eudragit® RSPO, Eudragit® FS100, Kollidon® VA64 and Plasdone™ K-29/32. The amorphous solubility, nucleation induction time, and particle size analysis of nifedipine in a supersaturated solution were performed with and without the presence of polymers, alone or in combination. Read More

Mol Pharm 2022 02 3;19(2):472-483. Epub 2022 Jan 3.

Department of Pharmaceutics, College of Pharmacy, University of Minnesota, Minneapolis, Minnesota 55455, United States.

Four model compounds, nifedipine, indomethacin, felodipine, and ketoconazole, all with nearly identical glass transition temperatures, were chosen to study the effects of thermodynamics and molecular mobility on their crystallization propensities. The time and temperature dependence of the crystallization induction time of each compound was determined by differential scanning calorimetry (DSC) and enabled the generation of their time-temperature-transformation (TTT) diagrams. The relaxation times (τ) were measured by dielectric spectroscopy, and the Gibbs free energy (Δ) and entropy (Δ) difference between the crystalline and amorphous states were obtained by DSC. Read More

Pharm Res 2021 Dec 20;38(12):2119-2127. Epub 2021 Dec 20.

Molecular Pharmaceutics Lab., College of Pharmaceutical Sciences, Ritsumeikan University, 1-1-1, Noji-higashi, Kusatsu, Shiga, 525-8577, Japan.

Purpose: The intestinal fluid pH is maintained by the bicarbonate buffer system that shows unique properties regarding drug dissolution. Nevertheless, current compendial dissolution tests use phosphate buffers. The purpose of the present study was to investigate the effect of bicarbonate and phosphate buffers on the dissolution profiles of amorphous solid dispersions (ASD) composed of ionizable polymers. Read More

Polymers (Basel) 2021 Aug 31;13(17). Epub 2021 Aug 31.

Faculty of Pharmaceutical Sciences, Burapha University, Chonburi 20131, Thailand.

Ternary solid solutions composed of nifedipine (NDP), amino methacrylate copolymer (AMCP), and polysorbate (PS) 20, 60, or 65 were prepared using a solvent evaporation method. The dissolution profiles of NDP were used to study the effect of the addition of polysorbate based on hydrophilic properties. A solid solution of NDP and AMCP was recently developed; however, the dissolution of NDP was <70%. Read More