title: Nicotine-magnesium aluminum silicate microparticle surface modified with chitosan for mucosal delivery.
abstract: Magnesium aluminum silicate (MAS), a negatively charged clay, and nicotine (NCT), a basic drug, can interact electrostatically to form microparticles. Chitosan (CS) was used for the surface modification of the microparticles, and a lyophilization method was used to preserve the original particle morphology. The microparticles were characterized in terms of their physicochemical properties, NCT content, mucoadhesive properties, and release and permeation across porcine esophageal mucosa. The results showed that the microparticles formed via electrostatic interaction between MAS and protonated NCT had an irregular shape and that their NCT content increased with increasing NCT ratios in the microparticle preparation solution. High molecular weight CS (800 kDa) adsorbed to the microparticle surface and induced a positive surface charge. CS molecules intercalated into the MAS silicate layers and decreased the crystallinity of the microparticles, leading to an increase in the release rate and diffusion coefficient of NCT from the microparticles. Moreover, the microparticle surface modified with CS was found to have higher NCT permeation fluxes and mucoadhesive properties, which indicated the significant role of CS for NCT mucosal delivery. However, the enhancement of NCT permeation and of mucoadhesive properties depended on the molecular weight and concentration of CS. These findings suggest that NCT-MAS microparticle surface modified with CS represents a promising mucosal delivery system for NCT.
authors.affiliation: Faculty of Pharmaceutical Sciences, Khon Kaen University, Khon Kaen 40002, Thailand.
authors.forename: Watchara
authors.initials: W
authors.lastname: Kanjanakawinkul
authors.forename: Thomas
authors.initials: T
authors.lastname: Rades
authors.forename: Satit
authors.initials: S
authors.lastname: Puttipipatkhachorn
authors.forename: Thaned
authors.initials: T
authors.lastname: Pongjanyakul
mesh_terms: D000268:Adhesiveness / Q000187:drug effects; D058956:Administration, Mucosal; D017607:Aluminum Compounds / Q000737:chemistry*; D000818:Animals; D002152:Calorimetry, Differential Scanning; D048271:Chitosan / Q000737:chemistry*; D016503:Drug Delivery Systems; D006863:Hydrogen-Ion Concentration; D066298:In Vitro Techniques; D017616:Magnesium Compounds / Q000737:chemistry*; D008863:Microspheres; D009538:Nicotine / Q000008:administration & dosage* / Q000494:pharmacology*; D010316:Particle Size; D010539:Permeability / Q000187:drug effects; D017640:Silicates / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared; D055672:Static Electricity; D013499:Surface Properties; D034421:Sus scrofa; D014961:X-Ray Diffraction
chemical_list: D017607:Aluminum Compounds; D017616:Magnesium Compounds; D017640:Silicates; D009538:Nicotine; C033065:aluminum magnesium silicate; D048271:Chitosan
keywords: Chitosan; Magnesium aluminum silicate; Microparticles; Mucosal delivery; Nicotine