RESUMO
The poorly water soluble antidiabetic drug gliclazide was selected to study the effect of excipients on dissolution rate enhancement. Ordered mixtures of micronized gliclazide with lactose, mannitol, sorbitol, maltitol and sodium chloride were prepared by manual shaking of glass vials containing the drug and excipient(s). Different water soluble excipients, addition of surfactant and superdisintegrant, drug concentration and carrier particle size influenced the dissolution rate of the drug. Dissolution rate studies of the prepared ordered mixtures revealed an increase in drug dissolution with all water soluble excipients. The order of dissolution rate improvement for gliclazide was mannitol > lactose > maltitol > sorbitol > sodium chloride. Composite granules of the particle size range 355-710 µm were superior in increasing the drug dissolution rate from ordered mixtures. Reducing the carrier particle size decreased the dissolution rate of the drug as well as the increase in drug concentration. Kinetic modeling of drug release data fitted best the Hixson-Crowell model, which indicates that all the ordered mixture formulations followed the cube root law fairly well.
Assuntos
Composição de Medicamentos/métodos , Sistemas de Liberação de Medicamentos , Gliclazida/química , Hipoglicemiantes/química , Diabetes Mellitus Tipo 2/tratamento farmacológico , Portadores de Fármacos/química , Excipientes/química , Gliclazida/uso terapêutico , Humanos , Hipoglicemiantes/uso terapêutico , Lactose/química , Maltose/análogos & derivados , Maltose/química , Modelos Teóricos , Tamanho da Partícula , Farmacocinética , Dodecilsulfato de Sódio/química , Solubilidade , Amido/análogos & derivados , Amido/química , Álcoois Açúcares/química , Tensoativos/química , Suspensões/química , ÁguaRESUMO
Modification of the surface properties of particles, which is usually achieved by coating, is desirable to maintain and enhance the utility of these particles. Saving of time, energy, number of additives, process steps and consequently, the cost of the coating process leads to development of dry coating processes using mechanical methods which exclude any liquid solvent or binder solution and are environmentally safe, and cost-effective. Mechanofusion, hybridization, magnetic assisted impaction coating, theta-composer, rotating fluidized bed coating, pressure swing granulation and high shear mixing have been extensively patented and reported in the scientific literature. These mechanical methods have found multidisciplinary applications in drug development and drug delivery. Various devices available for the dry coating process, their principle, method of working, benefits and limitations along with various applications relevant to the pharmaceutical field are discussed in the current article.
