{"title":"Dissolution profiles of high-dose salt-form drugs in bicarbonate buffer and phosphate buffer.","authors":"Yuki Tarumi, Kiyohiko Sugano","doi":"10.1016/j.xphs.2024.10.025","DOIUrl":null,"url":null,"abstract":"<p><p>The purpose of the present study was to compare the dissolution profiles of high-dose salt-form drugs in bicarbonate buffer (BCB) and phosphate buffer (PPB) focusing on the pH changes in the bulk phase. The pH titration curves of BCB and PPB (pH 6.5, buffer capacity (β) = 4.4 mmol/L/pH unit) were first theoretically calculated and experimentally validated. For dissolution tests, six drug salts with an acid counterion, one drug salt with a weak base counterion, and one free acid drug were employed (125 to 800 mg clinical dose). The dose/fluid volume ratio (Dose/FV) was aligned with the clinical condition. In the pH titration study, the pH value decreased below pH 6.0 by adding HCl > 2.8 mmol/L (BCB) or > 1.6 mmol/L (PPB) and increased above pH 7.0 by adding NaOH > 2.0 mmol/L (BCB) or > 2.4 mmol/L (PPB). In the dissolution test, even though the initial pH and β values were the same, the pH value at 4 h was lower in PPB than in BCB in all cases. For the drug salts with an acid counterion, the area under the dissolution curve was 1.2 to 2.6-fold lower in BCB than in PPB. A marked precipitation process was observed in BCB, but less pronounced or absent in PPB. The results of this study suggest the use of BCB and a clinically equivalent Dose/FV may be valuable in predicting the oral absorption of high-dose drug salts.</p>","PeriodicalId":16741,"journal":{"name":"Journal of pharmaceutical sciences","volume":null,"pages":null},"PeriodicalIF":3.7000,"publicationDate":"2024-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of pharmaceutical sciences","FirstCategoryId":"3","ListUrlMain":"https://doi.org/10.1016/j.xphs.2024.10.025","RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"CHEMISTRY, MEDICINAL","Score":null,"Total":0}
引用次数: 0
Abstract
The purpose of the present study was to compare the dissolution profiles of high-dose salt-form drugs in bicarbonate buffer (BCB) and phosphate buffer (PPB) focusing on the pH changes in the bulk phase. The pH titration curves of BCB and PPB (pH 6.5, buffer capacity (β) = 4.4 mmol/L/pH unit) were first theoretically calculated and experimentally validated. For dissolution tests, six drug salts with an acid counterion, one drug salt with a weak base counterion, and one free acid drug were employed (125 to 800 mg clinical dose). The dose/fluid volume ratio (Dose/FV) was aligned with the clinical condition. In the pH titration study, the pH value decreased below pH 6.0 by adding HCl > 2.8 mmol/L (BCB) or > 1.6 mmol/L (PPB) and increased above pH 7.0 by adding NaOH > 2.0 mmol/L (BCB) or > 2.4 mmol/L (PPB). In the dissolution test, even though the initial pH and β values were the same, the pH value at 4 h was lower in PPB than in BCB in all cases. For the drug salts with an acid counterion, the area under the dissolution curve was 1.2 to 2.6-fold lower in BCB than in PPB. A marked precipitation process was observed in BCB, but less pronounced or absent in PPB. The results of this study suggest the use of BCB and a clinically equivalent Dose/FV may be valuable in predicting the oral absorption of high-dose drug salts.
期刊介绍:
The Journal of Pharmaceutical Sciences will publish original research papers, original research notes, invited topical reviews (including Minireviews), and editorial commentary and news. The area of focus shall be concepts in basic pharmaceutical science and such topics as chemical processing of pharmaceuticals, including crystallization, lyophilization, chemical stability of drugs, pharmacokinetics, biopharmaceutics, pharmacodynamics, pro-drug developments, metabolic disposition of bioactive agents, dosage form design, protein-peptide chemistry and biotechnology specifically as these relate to pharmaceutical technology, and targeted drug delivery.