Development and evaluation of hydrophilic colloid matrix of famotidine tablets

Abstract

The objective of the present study was to develop a once-daily sustained-release (SR) matrix tablet of famotidine. Nine different formulations (F1-F9) were prepared by direct compression method using Avicel PH101 as filler/binder in the range of 41-27% in F1-F3, 18-22% in F4-F7, and 16-18% in F8-F9 and hydroxypropyl methylcellulose (4,000 cps) as hydrophilic matrix was used in F1-F3 from 19% to 30%, around 40% in F4-F7, and 42-45% in F8-F9. Talc and Aerosil were added in the ratio of 0.7-1.2%. The tablets were subjected to various physical parameters including weight variation test, hardness, thickness, diameter, friability, and in vitro release studies. Assay was also performed according to the USP 30 NF 25 procedure. The results of the physical parameters and assay were found to be within the acceptable range. In vitro dissolution results indicated that formulation F4-F7, having around 40% of rate control polymer, produced a SR pattern throughout 24 h. F1-F3 showed drug release at a faster rate, while F8-F9 released much slower, i.e., <80% in 24 h. Model-dependent and model-independent methods were used for data analysis and the best results were observed for F4 in zero order (r(2) = 0.984) and F6 in Korsmeyer and Higuchi (r(2) = 0.992 and 0.988). The parameter n indicated anomalous diffusion, while beta in Weibull showed a parabolic curve with higher initial slope. The f(2) similarity test was performed taking F4 as a reference formulation. Only the F5-F7 formulations were similar to the reference formulation F4. The mean dissolution time was around 10 h for the successful formulation.

Fig. 1

In vitro dissolution profile of famotidine SR formulations F1–F9

Fig. 2

Zero-order rate plot of famotidine SR formulations (F1–F9)

Fig. 3

First-order kinetics (semilogarithmic plot of time vs. percent drug remaining ) of F1–F9 famotidine SR formulations

Fig. 4

Higuchi kinetics (percent cumulative drug release vs. square root of time) of famotidine SR (F1–F9) formulations

Fig. 5

The model of Korsmeyer et al. (log time vs. log cumulative percent drug release) of famotidine F1–F9 SR formulations

Fig. 6

Hixson’s cube root plot (time vs. percent cube root remaining where is taken as the cube root of percent initial drug load and as the cube root of percent drug dissolved at time t) of famotidine SR (F1–F9) formulations

Fig. 7

Baker and Lonsdale model (where F is the fraction drug release) of F1–F9 famotidine SR formulations

Fig. 8

Weibull model (log T vs. log dissolved amount of drug plot where m is the solution at time t)