title: Mathematical Models for Controlled Drug Release Through pH-Responsive Polymeric Hydrogels.
abstract: Hydrogels consisting of weakly charged acidic/basic groups are ideal candidates for carriers in oral delivery, as they swell in response to pH changes in the gastrointestinal tract, resulting in drug entrapment at low pH conditions of the stomach and drug release at high pH conditions of the intestine. We have developed 1-dimensional mathematical models to study the drug release behavior through pH-responsive hydrogels. Models are developed for 3 different cases that vary in the level of rigor, which together can be applied to predict both in vitro (drug release from carrier) and in vivo (drug concentration in the plasma) behavior of hydrogel-drug formulations. A detailed study of the effect of hydrogel and drug characteristics and physiological conditions is performed to gain a fundamental insight into the drug release behavior, which may be useful in the design of pH-responsive drug carriers. Finally, we describe a successful application of these models to predict both in vitro and in vivo behavior of docetaxel-loaded micelle in a pH-responsive hydrogel, as reported in a recent experimental study.
authors.affiliation: Department of Chemical Engineering, IIT Roorkee, Uttarakhand 247667, India.
authors.forename: Ramya D
authors.initials: RD
authors.lastname: Manga
authors.affiliation: Department of Chemical Engineering, IIT Roorkee, Uttarakhand 247667, India. Electronic address: pkjchfch@iitr.ac.in.
authors.forename: Prateek K
authors.initials: PK
authors.lastname: Jha
mesh_terms: D000970:Antineoplastic Agents / Q000008:administration & dosage* / Q000737:chemistry / Q000493:pharmacokinetics; D003692:Delayed-Action Preparations / Q000737:chemistry*; D000077143:Docetaxel; D065546:Drug Liberation; D041981:Gastrointestinal Tract / Q000378:metabolism; D006801:Humans; D020100:Hydrogels / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D008823:Micelles; D008954:Models, Biological; D008956:Models, Chemical; D011108:Polymers / Q000737:chemistry*; D043823:Taxoids / Q000008:administration & dosage* / Q000737:chemistry / Q000493:pharmacokinetics
chemical_list: D000970:Antineoplastic Agents; D003692:Delayed-Action Preparations; D020100:Hydrogels; D008823:Micelles; D011108:Polymers; D043823:Taxoids; D000077143:Docetaxel
keywords: controlled release; diffusion; gastrointestinal; hydrogels; mathematical model; oral drug delivery; pharmacokinetics; polyelectrolytes; polymeric drug carrier; thermodynamics