Effect of preparation conditions on morphology, drug content and release profiles of poly(hydroxybutyrate) microparticles containing piroxicam

Abstract

No presente estudo foram preparadas micropartículas de poli(hidroxibutirato) contendo piroxicam pela técnica de emulsão-evaporação do solvente. A influência de alguns parâmetros do processo sobre a eficiência de encapsulação do fármaco foi avaliada por meio de um planejamento fatorial do tipo 2 3 . A eficiência de encapsulação do piroxicam variou de 5,5 a 89,8%. Micropartículas ocas e irregulares, contendo cristais de fármaco na superfície, foram obtidas quando se utilizou 5 mL de clorofórmio como fase interna da emulsão. Com o ensaio de liberação in vitro evidenciouse que, após 8 h, todo o fármaco havia sido liberado para o meio. Micropartículas esféricas com superfície externa rugosa e porosa foram obtidas quando se utilizou 20 mL de diclorometano como fase interna e adicionou-se isopropanol à fase externa da emulsão. Essas microesferas foram capazes de controlar a liberação do piroxicam durante 50 h. Os resultados obtidos demonstraram que é possível obter micropartículas com características específicas pela otimização das condições empregadas no processo de encapsulação.In this study, poly(hydroxybutyrate) microparticles containing piroxicam were prepared by the oil-in-water emulsion-solvent evaporation method. The effects of some process conditions on drug content were determined using a 2 3 factorial design. The piroxicam loading efficiency varied from 5.5 to 89.8 %. Hollow and irregular microparticles with drug crystals on their surfaces were obtained when 5 mL of chloroform was used as the internal phase. In the release study, all of the piroxicam was released to the dissolution medium (phosphate buffer pH 7.4) after 8 h. Small spherical microspheres with a rough and porous polymeric matrix were obtained when 20 mL of dichloromethane was used as the internal phase and isopropanol was added to the external aqueous phase. These microspheres controlled the piroxicam release for approximately 50 h. The results demonstrated that it is possible to obtain microparticles with specific characteristics by the optimization of the process conditions.

Microparticles prepared from biodegradable polyhydroxyalkanoates as matrix for encapsulation of cytostatic drug

“…The study of DOX release kinetics as dependent upon the drug content of the matrix of microparticles showed that drug release rate became almost 1.5 times faster as DOX content of the matrix of microparticles was increased from 1 to 10 %. The results obtained in this study compare well with the data on the release kinetics of gentamicin from P3HB/ 3HV microparticles [36]; tramadol, piroxicam, and ibuprofen from P3HB microparticles [8,10,11].…”

“…At the present time, PHAs are used to prepare microparticles loaded with analgesics [8] and anti-inflammatory drugs; their release kinetics has been studied quite well [9][10][11][12]. PHA microparticles, films, and 3D matrices are promising carriers for antibiotics, enabling the sustained release of the drug [13][14][15][16].…”

Caboxymetylcellulose/Gelatin Blends Loaded with Piroxicam: Preparation, Characterization and Evaluation of in Vitro Release Profile

“…Prepared microparticles of cellulose acetate butyrate and poly (3-hydroxibutyrate) (PHB) containing piroxicam, in which all formulations studied had around 50% of the total amount of the non encapsulated drug added with the drug content in the microparticles being practically the same, around 15 mg. Prepared piroxicam microparticles using PHB as matrix, and confirmed that the EE% varied from 5.5 to 89.8% [20]. The best encapsulation indices were recorded by preparing polycarbonate microparticles which, under the conditions described in the method, attained an EE% of 95% for the piroxicam.…”

Biodegradable Nanoparticles Obtained From Zein as a Drug Delivery System for Terpinen-4-Ol

“…13,14,10 Because of their high biocompatibility and ability to form nanospheres through coacervation, zeins are natural raw materials with potential uses in tissue engineering, drug delivery systems, and biomedicine. 1,15 Biodegradable NPs have received considerable attention because of their potential usefulness in the development of strategies for the topical delivery of oils and therapeutic drugs, [16][17][18] particularly when drug penetration into the dermis is desirable. 19 Most delivery systems with properties suitable for controlled release are microscale beads or gels.…”