title: Preparation and evaluation of solid dispersion for nitrendipine-carbopol and nitrendipine-HPMCP systems using a twin screw extruder.
abstract: In the present study, we prepared solid dispersions of the poorly water-soluble drug nitrendipine (NIT) using the twin screw extruder method with high-molecular-weight substances, hydroxypropylmethylcellulosephthalate (HPMCP) and Carbopol (CAR), as carriers. Powder X-ray diffraction (PXRD) and differential scanning calorimetry (DSC) evaluation showed that solid dispersions can be formed when NIT-HPMCP and NIT-CAR mixtures are treated with the twin screw extruder method. Fourier Transformation IR Spectroscopy (FT-IR) obtained with NIT-HPMCP and NIT-CAR solid dispersions indicated the presence of hydrogen bonding between the drug and the carriers. NIT-CAR solid dispersions were found to give somewhat higher dissolution than crystalline NIT and physical mixtures, while the dissolution of NIT-HPMCP solid dispersions was markedly decreased compared with the crystalline NIT and physical mixtures. These findings indicated that CAR has a greater ability to improve the dissolution of NIT than HPMCP when a twin screw extruder was employed to prepare the solid dispersions. The twin screw extruder method can be used as a simple and effective method for the preparation of solid dispersions to improve the dissolution properties of poorly water-soluble drugs when choosing proper polymers as carriers.
authors.affiliation: Department of Pharmaceutics, Shenyang Pharmaceutical University, PR China.
authors.forename: Liang
authors.initials: L
authors.lastname: Wang
authors.forename: Fu De
authors.initials: FD
authors.lastname: Cui
authors.forename: Tomokazu
authors.initials: T
authors.lastname: Hayase
authors.forename: Hisakazu
authors.initials: H
authors.lastname: Sunada
mesh_terms: D000180:Acrylic Resins; D002152:Calorimetry, Differential Scanning; D002626:Chemistry, Pharmaceutical; D003460:Crystallization; D004337:Drug Carriers / Q000737:chemistry*; D006860:Hydrogen Bonding; D008747:Methylcellulose / Q000031:analogs & derivatives* / Q000737:chemistry; D015394:Molecular Structure; D008970:Molecular Weight; D009568:Nitrendipine / Q000737:chemistry*; D011145:Polyvinyls / Q000737:chemistry*; D012995:Solubility; D017550:Spectroscopy, Fourier Transform Infrared; D013678:Technology, Pharmaceutical / Q000295:instrumentation / Q000379:methods*; D014961:X-Ray Diffraction
chemical_list: D000180:Acrylic Resins; D004337:Drug Carriers; D011145:Polyvinyls; C006912:carboxypolymethylene; D008747:Methylcellulose; C053309:hydroxypropyl methylcellulose phthalate; D009568:Nitrendipine