title: Continuous preparation of polymer coated drug crystals by solid hollow fiber membrane-based cooling crystallization.
abstract: A facile way to continuously coat drug crystals with a polymer is needed in controlled drug release. Conventional polymer coating methods have disadvantages: high energy consumption, low productivity, batch processing. A novel method for continuous polymer coating of drug crystals based on solid hollow fiber cooling crystallization (SHFCC) is introduced here. The drug acting as the host particle and the polymer for coating are Griseofulvin (GF) and Eudragit RL100, respectively. The polymer's cloud point temperature in its acetone solution was determined by UV spectrophotometry. An acetone solution of the polymer containing the drug in solution as well as undissolved drug crystals in suspension were pumped through the tube side of the SHFCC device; a cold liquid was circulated in the shell side to rapidly cool down the feed solution-suspension in the hollow-fiber lumen. The polymer precipitated from the solution and coated the suspended crystals due to rapid temperature reduction and heterogeneous nucleation; crystals formed from the solution were also coated by the polymer. Characterizations by scanning electron microscopy, thermogravimetric analysis, laser diffraction spectroscopy, X-ray diffraction, Raman spectroscopy, and dissolution tests show that a uniformly coated, free-flowing drug/product can be obtained under appropriate operating conditions without losing the drug's pharmaceutical properties and controlled release characteristics.
authors.affiliation: Otto York Department of Chemical, Biological and Pharmaceutical Engineering, New Jersey Institute of Technology, University Heights, Newark, NJ 07102, USA. Electronic address: dc224@njit.edu.
authors.forename: Dengyue
authors.initials: D
authors.lastname: Chen
authors.affiliation: Otto York Department of Chemical, Biological and Pharmaceutical Engineering, New Jersey Institute of Technology, University Heights, Newark, NJ 07102, USA. Electronic address: ds64@njit.edu.
authors.forename: Dhananjay
authors.initials: D
authors.lastname: Singh
authors.affiliation: Otto York Department of Chemical, Biological and Pharmaceutical Engineering, New Jersey Institute of Technology, University Heights, Newark, NJ 07102, USA. Electronic address: sirkar@njit.edu.
authors.forename: Kamalesh K
authors.initials: KK
authors.lastname: Sirkar
authors.affiliation: School for Engineering of Matter, Transport and Energy, Arizona State University, Tempe, AZ 85287, USA. Electronic address: Robert.Pfeffer@asu.edu.
authors.forename: Robert
authors.initials: R
authors.lastname: Pfeffer
mesh_terms: D000180:Acrylic Resins / Q000737:chemistry*; D011232:Chemical Precipitation; D002626:Chemistry, Pharmaceutical / Q000379:methods; D003460:Crystallization; D003692:Delayed-Action Preparations; D005079:Excipients / Q000737:chemistry*; D006118:Griseofulvin / Q000008:administration & dosage* / Q000737:chemistry; D011108:Polymers / Q000737:chemistry*; D013696:Temperature; D014961:X-Ray Diffraction
chemical_list: D000180:Acrylic Resins; D003692:Delayed-Action Preparations; D005079:Excipients; D011108:Polymers; D006118:Griseofulvin; C050528:Eudragit RS
keywords: Drug crystals; Membrane-based cooling crystallization; Polymer coating; Solid hollow fiber