RESUMEN
The properties of dry-coated paracetamol particles(fast-dissolving model drug)with carnauba wax particles as the coating agent(dissolution retardant)were investigated.Raman mapping technique was used to non-destructively examine the thickness and homogeneity of coated particles.The results showed that the wax existed in two forms on the surface of the paracetamol particles,forming a porous coating layer:i)whole wax particles on the surface of paracetamol and glued together with other wax surface particles,and ii)deformed wax particles spread on the surface.Regardless of the final particle size fraction(between 100 and 800 μm),the coating thickness had high variability,with average thickness of 5.9±4.2 μm.The ability of carnauba wax to decrease the dissolution rate of paracetamol was confirmed by dissolution of powder and tablet formulations.The dissolution was slower for larger coated particles.Tableting further reduced the dissolution rate,clearly indicating the impact of subsequent formulation processes on the final quality of the product.
RESUMEN
OBJECTIVE: To establish a rapid and nondestructive method to determine coating thickness of the total saponin of Radix Bupleuri enteric coated tablets by near infrared spectroscopy (NIRS) analytical technique. METHODS: Spectral pretreating methods, wavenumber selection and factors of NIRS were discussed in detail. Different modeling methods were compared and the methodology of model was investigated. RESULTS: Partial least squares regression (PLSR) was used for building the quantitative calibration model. Correlation coefficients(r), root-mean-squares error of cross-validation (RMSECV), and root mean square error of prediction (RMSEP) obtained by PLSR model were 0.9915, 3.6 and 3.24 μm respectively. CONCLUSION: Predicted results show that the established method is rapid, nondestructive, and reliable, which can be applied to the online monitor of Chinese medicine tablets coating process.