PURPOSE: Particle size of a drug is an important factor that affects thermodynamic solubility and oral absorption of drug molecules. Weight fraction of different particle sizes in a polydisperse powder together with Noyes Whitney parameters (diffusion coefficient, solubility, density of the drug, boundary layer thickness and dissolution volume) can be used to predict dissolution and absorption of drug molecules. Such a simulation can be a valuable tool in setting up guidance with regards to dependence of dissolution and absorption on particle size. MATERIALS AND METHODS: In this note a modified method is reported to predict dissolution of polydisperse drug powder. These use simplified equations developed from a set of differential equations described previously. The idea was to convert all the terms in one single equation which can then be solved by a Matlab program. CONCLUSION: Discrepancies not reported earlier have been discussed to get the same results as reported previously.
PURPOSE: Particle size of a drug is an important factor that affects thermodynamic solubility and oral absorption of drug molecules. Weight fraction of different particle sizes in a polydisperse powder together with Noyes Whitney parameters (diffusion coefficient, solubility, density of the drug, boundary layer thickness and dissolution volume) can be used to predict dissolution and absorption of drug molecules. Such a simulation can be a valuable tool in setting up guidance with regards to dependence of dissolution and absorption on particle size. MATERIALS AND METHODS: In this note a modified method is reported to predict dissolution of polydisperse drug powder. These use simplified equations developed from a set of differential equations described previously. The idea was to convert all the terms in one single equation which can then be solved by a Matlab program. CONCLUSION: Discrepancies not reported earlier have been discussed to get the same results as reported previously.