Hydrophobic weak acid polymers as controlled release carriers.
Poly(carboxyalkyl methacrylates) were studied as a cationic-drug delivery system, at pH 6.8 and 8.0. Different polymer/drug complexes were used to prepare compressed tablets. By kinetics experiments, we have found that drug release is dependent on both the hydrophobicity of the whole complex and the pH of the environment. Furthermore, a mechanism of dissociation/erosion clearly describes the drug release from a complex formed by a polymer soluble at target pH; otherwise, a mechanism of dissolution/diffusion is depicted. Additionally, we have observed that hydrophilic fillers increase the drug release rate. Since our results using different polymer/drug complexes exhibit pH-sensitive drug release, we propose that the poly(carboxyalkyl methacrylates) have potential as a colon-specific drug-delivery system.
Facultad de Ciencias Químicas e Ingeniería, Universidad Autónoma de Baja California, Calzada Universidad 14418, Parque Industrial Internacional, Tijuana, México. jmcornejo@uabc.mx
Jose M
JM
Cornejo-Bravo
Yareli
Y
Partida-Soria
Aracely
A
Serrano-Medina
Karla
K
Espinoza-Dueñas
Marco A
MA
Ramos
Angel
A
Licea-Claverie
D002412:Cations / Q000737:chemistry; D003692:Delayed-Action Preparations / Q000737:chemistry*; D004573:Electrolytes / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D057927:Hydrophobic and Hydrophilic Interactions; D007700:Kinetics; D004364:Pharmaceutical Preparations / Q000008:administration & dosage*; D011109:Polymethacrylic Acids / Q000737:chemistry*; D012995:Solubility
D002412:Cations; D003692:Delayed-Action Preparations; D004573:Electrolytes; D004364:Pharmaceutical Preparations; D011109:Polymethacrylic Acids