title: Multilayer encapsulated mesoporous silica nanospheres as an oral sustained drug delivery system for the poorly water-soluble drug felodipine.
abstract: We used a combination of mesoporous silica nanospheres (MSN) and layer-by-layer (LBL) self-assembly technology to establish a new oral sustained drug delivery system for the poorly water-soluble drug felodipine. Firstly, the model drug was loaded into MSN, and then the loaded MSN were repeatedly encapsulated by chitosan (CHI) and acacia (ACA) via LBL self-assembly method. The structural features of the samples were studied using scanning electron microscopy (SEM), transmission electron microscopy (TEM) and nitrogen adsorption. The encapsulating process was monitored by zeta-potential and surface tension measurements. The physical state of the drug in the samples was characterized by differential scanning calorimetry (DSC) and X-ray diffractometry (XRD). The influence of the multilayer with different number of layers on the drug release rate was studied using thermal gravimetric analysis (TGA) and surface tension measurement. The swelling effect and the structure changes of the multilayer were investigated to explore the relationship between the drug release behavior and the state of the multilayer under different pH conditions. The stability and mucosa adhesive ability of the prepared nanoparticles were also explored. After multilayer coating, the drug release rate was effectively controlled. The differences in drug release behavior under different pH conditions could be attributed to the different states of the multilayer. And the nanoparticles possessed good stability and strong mucosa adhesive ability. We believe that this combination offers a simple strategy for regulating the release rate of poorly water-soluble drugs and extends the pharmaceutical applications of inorganic materials and polymers.
authors.affiliation: Department of Pharmaceutics, Shenyang Pharmaceutical University, P.O. Box 32, Liaoning Province, Shenyang 110016, PR China.
authors.forename: Liang
authors.initials: L
authors.lastname: Hu
authors.affiliation: English Teaching Department, School of Basic Courses, Shenyang Pharmaceutical University, Wenhua Road 103, Shenyang 110016, PR China.
authors.forename: Hongrui
authors.initials: H
authors.lastname: Sun
authors.affiliation: Department of Pharmaceutics, Shenyang Pharmaceutical University, P.O. Box 32, Liaoning Province, Shenyang 110016, PR China.
authors.forename: Qinfu
authors.initials: Q
authors.lastname: Zhao
authors.affiliation: Department of Pharmaceutics, Shenyang Pharmaceutical University, P.O. Box 32, Liaoning Province, Shenyang 110016, PR China.
authors.forename: Ning
authors.initials: N
authors.lastname: Han
authors.affiliation: Department of Pharmaceutics, Shenyang Pharmaceutical University, P.O. Box 32, Liaoning Province, Shenyang 110016, PR China.
authors.forename: Ling
authors.initials: L
authors.lastname: Bai
authors.affiliation: Department of Pharmaceutics, Shenyang Pharmaceutical University, P.O. Box 32, Liaoning Province, Shenyang 110016, PR China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Department of Pharmaceutics, Shenyang Pharmaceutical University, P.O. Box 32, Liaoning Province, Shenyang 110016, PR China.
authors.forename: Tongying
authors.initials: T
authors.lastname: Jiang
authors.affiliation: Department of Pharmaceutics, Shenyang Pharmaceutical University, P.O. Box 32, Liaoning Province, Shenyang 110016, PR China. Electronic address: silingwang@syphu.edu.cn.
authors.forename: Siling
authors.initials: S
authors.lastname: Wang
mesh_terms: D000284:Administration, Oral; D000327:Adsorption; D002152:Calorimetry, Differential Scanning / Q000379:methods; D048271:Chitosan / Q000737:chemistry; D004337:Drug Carriers / Q000737:chemistry; D016503:Drug Delivery Systems / Q000379:methods; D015736:Felodipine / Q000737:chemistry*; D008855:Microscopy, Electron, Scanning / Q000379:methods; D046529:Microscopy, Electron, Transmission / Q000379:methods; D054118:Nanospheres / Q000737:chemistry*; D016062:Porosity; D012822:Silicon Dioxide / Q000737:chemistry*; D012995:Solubility; D013818:Thermogravimetry / Q000379:methods; D014867:Water / Q000737:chemistry*
chemical_list: D004337:Drug Carriers; D014867:Water; D012822:Silicon Dioxide; D048271:Chitosan; D015736:Felodipine
keywords: Felodipine; Layer-by-layer; Mesoporous silica nanospheres; Poorly water-soluble drug; Sustained release