PH-independent sustained release matrix tablet containing doxazosin mesylate: Effect of citric acid

Kwang Ho Cha, Thanh Huyen Tran, Min Soo Kim, Jeong Soo Kim, Hee Jun Park, Junsung Park, Wonkyung Cho, Sung Joo Hwang

Research output: Contribution to journalArticlepeer-review

8 Citations (Scopus)


The aim of this study was to develop a pH-independent sustained release matrix tablets of doxazosin mesylate. The matrix tablets were prepared by direct compression technique using polyethylene oxide, sodium alginate and citric acid as a pH modifier. Formulations were evaluated for an in vitro drug release study, erosion study, and the microenvironmental pH was studied using the pH indicator methyl red. For formulations without citric acid, the extent and rate of drug release in simulated gastric fluid were much higher than those in simulated intestinal fluid. By adding the citric acid, the drug release rate in simulated intestinal fluid was increased, and microenvironmental pH values within the tablets were maintained at low pH during drug release. Furthermore, drug release from the matrix tablet containing 20% w/w citric acid was comparable to that from a commercial product, Cardura® XL, and a pHindependent release could be achieved. Therefore, the incorporation of citric acid as a pH modifier to Polyethylen oxide-sodium alginate matrix tablets effectively produced pHindependent doxazocin mesylate release profiles.

Original languageEnglish
Pages (from-to)2003-2009
Number of pages7
JournalArchives of pharmacal research
Issue number12
Publication statusPublished - 2010 Dec

Bibliographical note

Funding Information:
This study was supported by a grant of the Korean Health Technology R&D Project, Ministry for Health, Welfare & Family Affairs, Republic of Korea (A092018), and Priority Research Centers Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology (2009-0093815).

All Science Journal Classification (ASJC) codes

  • Molecular Medicine
  • Drug Discovery
  • Organic Chemistry


Dive into the research topics of 'PH-independent sustained release matrix tablet containing doxazosin mesylate: Effect of citric acid'. Together they form a unique fingerprint.

Cite this