Formula optimization of theophylline controlled-release tablet based on artificial neural networks
Introduction
In the design of pharmaceutical formulations, it is important to optimize pharmaceutical responses relating to its effectiveness, safety and usefulness to patients. A computer optimization technique, based on a response surface method (RSM), has often been used for selecting pharmaceutical formulations [1], [2]. The optimization procedure based on RSM includes statistical experimental designs, multiple regression analysis and mathematical optimization algorithms for seeking the best formulation under a set of constrained equations. Since theoretical relationships between response variables and causal factors are not clear, multiple regression analysis can be applied to the prediction of response variables on the basis of a second-order polynomial equation. The prediction of pharmaceutical responses based on the second-order polynomial equation, however, is often limited to low levels, resulting in the poor estimation of optimal formulations. To overcome the shortcomings in RSM, we developed a multi-objective simultaneous optimization technique in which an artificial neural network (ANN) was incorporated [3], [4], [5]. ANN is a learning system based on a computational technique which can simulate the neurological processing ability of the human brain [6], and could be applied to quantifying a non-linear relationship between causal factors and pharmaceutical responses by means of iterative training of data obtained from a designed experiment.
The aim of the present study was to apply the simultaneous optimization method incorporating ANN to the development of a theophylline tablet, which has an optimized release behavior. Plasma concentrations of theophylline were predicted on the basis of pharmacokinetic analysis to obtain desirable release profiles of theophylline from the tablets. Controse, the mixture of hydroxypropylmethylcellulose (HPMC) and lactose, was employed as a gel-forming material while cornstarch was used as a disintegrant.
Section snippets
ANN architecture
Theoretical details of the hierarchical ANN have been given elsewhere. Briefly, the general structure of ANN has one input layer, one or more hidden layers and one output layer. Each layer has some units corresponding to neurons. The units in neighboring layers are fully interconnected with links corresponding to synapses. The strengths of connections between two units are called ‘weights’. ANN learns an approximate non-linear relationship by a training procedure, which involves varying weight
Materials and methods
Theophylline was purchased from Sigma–Aldrich (Tokyo, Japan). Controse 80/20 was generously supplied by Freund (Tokyo, Japan). Controse 80/20 is a powder mixture of HPMC and lactose in the weight ratio of 80 to 20, passing through mesh No. 45 in JIS gauge. Cornstarch, JP grade, was purchased from Kosakai (Tokyo, Japan).
Release behaviors of theophylline
Release behaviors of theophylline from the tablets in Table 1 are shown in Fig. 2. The fast release rate of theophylline during the initial stage and consecutive slow release in the following stage were observed. The tablets containing large amounts of cornstarch were partly disintegrated during the initial stage and then a hydrogel was gradually formed on the surface of the tablets. However, the initial disintegration was hardly observed in the tablets containing small amounts of cornstarch.
Acknowledgements
This work was supported by the Uehara Memorial Foundation.
References (18)
- et al.
Multi-objective simultaneous optimization based on artificial neural network in sustained release formulations
J. Control. Rel.
(1997) - et al.
Multi-objective simultaneous optimization based on artificial neural network in a ketoprofen hydrogel formula containing O-ethylmenthol as a percutaneous absorption enhancer
Int. J. Pharm.
(1997) - et al.
Simultaneous optimization for several characteristics concerning percutaneous absorption and skin damage of ketoprofen hydrogels containing d-limonene
Int. J. Pharm.
(1991) - et al.
Response Surface, Design and Analysis
(1987) - et al.
Pharmaceutical Experimental Design
(1999) - et al.
Artificial neural network as a novel method to optimize pharmaceutical formulations
Pharm. Res.
(1999) - et al.
Artificial neural networks: Implications for pharmaceutical sciences
Drug Dev. Ind. Pharm.
(1995) - et al.
Explorations in Parallel Distributed Processing
(1988) Introduction to backpropagation neural network computation
Pharm. Res.
(1993)
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