A new method for the preparation of pure acamprosate calcium with a micron particle size

Document Type : Research Paper


Department of Chemical Technologies, Iranian Research Organization for Science and Technology, Tehran, Iran


Considering that preparing microparticle drugs enhances their solubility and bioactivity, it is the pharmaceutics’ interest to have more information about the drug’s particle size; hence, it is essential to study a drug’s particle size and morphology. So far, no work has been done on the particle size of acamprosate calcium. In this work, micronized acamprosate calcium was first prepared, then its water solubility was investigated. To this aim, acamprosate calcium was synthesized from 1,3-propane sultone through two-step reactions. The resulting powder was then micronized using Triton-X-100 using the in situ micronization method. The resulting micronized particles were found to be highly pure (99.7 %). The micronized acamprosate calcium's particle size was less than 10 µm. Kinetic solubility studies showed that micronized acamprosate calcium's water solubility had improved compared to bulk particles of acamprosate calcium.

Graphical Abstract

A new method for the preparation of pure acamprosate calcium with a micron particle size


  • A micron-sized acamprosate calcium sample was synthesized by using Triton-X-100.
  • The product has an acceptable purity and is in accordance with international U.S. pharmacopeia.
  • The kinetic solubility of acamprosate calcium was improved by size reduction. 


Main Subjects

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Volume 8, Issue 1
May 2022
Pages 17-23
  • Receive Date: 25 June 2022
  • Revise Date: 01 September 2022
  • Accept Date: 14 October 2022
  • First Publish Date: 14 October 2022