Evaluation of Coating Properties of Enteric-Coated Tablets Using Terahertz Pulsed Imaging

Abstract

We demonstrated the utility of TPI to identify structural defects within ECTs with poor acid resistance. TPI-derived parameters can aid in formulation development and quality control of ECTs.

Evaluation of critical process parameters for inter-tablet coating uniformity of active-coated GITS using Terahertz Pulsed Imaging

“…The assumption we make is that the refractive index (and in turn the coating density) is constant within a single batch of tablets, which we believe to be a fair assumption to make based on the results presented in the paper by Russe et al and May et al [26,27] as well as the study of Niwa et al which shows that subtle changes in moisture levels within a coating layer have no significant effect on the TPI results [28].…”

Review of Terahertz Pulsed Imaging for Pharmaceutical Film Coating Analysis

“…This work has been extended to detecting cracks between layers in bilayer tablets [30] where the adhesion integrity can be quantified based on the TII, which in turn can be correlated to layer separation tendency. TPI can also reveal structural defects in enteric coatings where the combination of coating thickness, coating uniformity, TEFPS and TII information can infer on the physiochemical properties of the coating and acid resistance [31]. The results of which were successfully validated against scanning electron microscopy (SEM), XµCT, acid uptake tests and loss on drying (LOD) test, a measure of water content in sample tablets.…”

Regulating the pH of bicarbonate solutions without purging gases: Application to dissolution testing of enteric coated tablets, pellets and microparticles

“…Unlike the spherical shape of the multiparticulate cores, tablets are not geometrically spherical, resulting in variations in coating uniformity on different areas of the tablet. The coating at the edges of the tablet surface was observed to be thinner than that at the center of the tablet surface, contributing to faster polymer dissolution in these areas and tablet disintegration (Niwa et al, 2014). These differences in the tablet and multiparticulate formulations make direct comparison of their dissolution behaviour a challenge; however, the marked acceleration of drug release from the microparticle formulation in comparison to pellets and tablets demonstrated its potential in improving in vivo performance of enteric coated products.…”