Use of bicarbonate buffer systems for dissolution characterization of enteric-coated proton pump inhibitor tablets

Abstract

Use of multiple dissolution media during in vitro testing, including high concentration bicarbonate buffer, would contribute to the efficient design of enteric-coated drug formulations.

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

“…Similar to previous reports, drug release rates from all three enteric coated dosage forms were rapid in phosphate buffers with no significant differences between the dissolution profiles (Amaral Silva et al, 2019;Merchant et al, 2014b;Shibata et al, 2016). In bicarbonate buffers, a significant drug release lag time was noted for enteric coated tablets and pellets, which was again in agreement with published studies (Amaral Silva et al, 2019;Merchant et al, 2014b;Shibata et al, 2016).…”

“…Similar to previous reports, drug release rates from all three enteric coated dosage forms were rapid in phosphate buffers with no significant differences between the dissolution profiles (Amaral Silva et al, 2019;Merchant et al, 2014b;Shibata et al, 2016). In bicarbonate buffers, a significant drug release lag time was noted for enteric coated tablets and pellets, which was again in agreement with published studies (Amaral Silva et al, 2019;Merchant et al, 2014b;Shibata et al, 2016). It was well documented that the dissolution of enteric polymers containing carboxylic groups was dependent on the composition of the dissolution media including the buffer species, molarity and ionic strength (Amaral Silva et al, 2019;Boni et al, 2007;Karkossa and Klein, 2017;Ozturk et al, 1988;Spitael and Kinget, 1977).…”

“…the pHysio-stat ® , pHysio-grad ® and the Auto pH system TM ) have been made available to provide a practical solution to regulate and stabilise the pH bicarbonate buffers and to simulate the pH gradients in the human intestinal lumen (Garbacz et al, 2014;Merchant et al, 2014b). Purging gases using these devices have been utilised by recent studies applying bicarbonate buffer-based dissolution methods (Jede et al, 2019;Karkossa and Klein, 2017;Shibata et al, 2016).…”

Assessing the influence of media composition and ionic strength on drug release from commercial immediate-release and enteric-coated aspirin tablets

“…As Blank CarbSIF does not contain phosphate ions, but a significantly higher bicarbonate concentration than the bicarbonate‐based buffer systems, 15 m m vs 10 m m , respectively, the bicarbonate concentration of Blank CarbSIF seems to be a major determinant for in‐vitro drug release of the EC aspirin formulations in an environment simulating average pH and ionic composition of small intestinal fluid. Shibata et al . reported similar observations from a study investigating the dissolution behaviour of proton pump inhibitor formulations bearing coatings made of different enteric polymers.…”

A Novel Multilayer Natural Coating for Fed-State Gastric Protection

“…Fumaric acid is an acid that is poorly soluble in water (~0.6% w/v) with a pKa of 3.03 [32]. On the other hand, citric acid is a highly water-soluble tri-carboxylic acid (59.2 g/100 mL) [33] with three pKa values of 3.1, 4.8, and 6.4 [34]. The aim of incorporating organic acids (with low pKa values) into the OC was to prevent excessive alginate ionisation at elevated gastric pH values (see Section 3.3 c).…”