A model of dissolution-controlled, diffusional drug release from non-swellable polymeric microspheres

Preparation and Evaluation of Sustained Release Matrix Tablets of Tramadol Hydrochloride Using Glyceryl Palmitostearate

“…To determine the mechanism of drug release from the formulations, the data were subjected to zero-order (Eq 1), first order (Eq 2) and Highuchi (Eq 3) release kinetics [19,20] M t = M 0 + k 0 t ….………………………… (1)…”

Numerical simulation of controlled nifedipine release from chitosan microgels

“…(9), the shape function N n (x) and M m (x) for the functions f(x) and g x (x), respectively, are defined as (12) in which ⌬L n is defined as the cloud length of the nth point, B(u) and˜B(u) are the linearly independent basis-function vectors which are given by…”

“…However, the drug release process is usually modeled with the classical Fick's diffusion equation integrating with appropriate boundary conditions or with the simplified expressions developed by Higuchi and Higuchi. [12][13][14][15] A mathematical theory with simultaneous consideration of drug dissolution and diffusion in the continuous matrices of microgels was put forward by Grassi et al 16 and fitted well to the experimentally measured temazeoan and medroxyprogesterone acetate release data. Recently, Hombreiro-Perez et al 2 pointed out that an adequate description of nifedipine release from microgels must consider drug dissolution, drug diffusion in the continuous matrices of microgels, and the limited solubility of nifedipine in the release medium.…”

“…(1) corresponds to the potential ratelimiting drug dissolution process. 12 It is observed that, when the drug loading concentration C 0 is smaller than the drug saturation concentration C s , eq. (1) is reduced to the classic Fick's diffusion equation.…”

Once Daily, High-Dose Mesalazine Controlled-Release Tablet for Colonic Delivery: Optimization of Formulation Variables Using Box–Behnken Design

“…The mean in vitro drug release data were fitted to different kinetic models, namely zero-order kinetics (19), first order (20), Higuchi (21), and Korsmeyer-Peppas (22) using regression analysis to evaluate the kinetics of drug release from the prepared matrices. The model which shows the highest value of coefficient of determination (R 2 ) was selected as the best model that describes the kinetics of drug release.…”