Related Experiment Video
Updated: Aug 16, 2025

Construction and Systematical Symmetric Studies of a Series of Supramolecular Clusters with Binary or Ternary Ammonium Triphenylacetates
Published on: February 15, 2016
Bromhexine and its fumarate salt: Crystal structures, Hirshfeld surfaces and dissolution study
Ya-An Zhang1, Cui-Min Yan2, Bai-Wang Sun2
1School of Pharmaceutical and Chemical Engineering, Chengxian College, Southeast University, Nanjing 210088, PR China.
Bromhexine, an expectorant drug, was repurposed to improve its solubility and bioavailability using a multicomponent crystal strategy with fumaric acid. This new crystal form demonstrated enhanced thermal stability and water solubility compared to the original drug.
Area of Science:
- Pharmaceutical Sciences
- Drug Discovery
- Crystallography
Background:
- Bromhexine is an expectorant with potential as a TMPRSS2 inhibitor for COVID-19 treatment.
- Poor solubility of bromhexine limits its bioavailability and therapeutic efficacy.
- Multicomponent crystal engineering is a strategy to enhance drug properties.
Purpose of the Study:
- To develop a new bromhexine crystal form with improved physicochemical properties.
- To investigate the potential of a bromhexine-fumaric acid cocrystal.
- To enhance bromhexine's solubility, bioavailability, and thermal stability.
Main Methods:
- Slow evaporation technique was used to synthesize bromhexine and its fumarate salt crystal.
- X-ray single-crystal diffraction, Thermogravimetric Analysis (TGA), and FT-IR spectroscopy were employed for characterization.
- Hirshfeld surface analysis was performed to study intermolecular interactions.
Main Results:
- A new bromhexine crystal and its fumarate salt crystal were successfully obtained.
- The multicomponent crystal exhibited improved thermal stability compared to bromhexine.
- Enhanced water solubility was observed for the bromhexine-fumaric acid cocrystal.
Conclusions:
- Multicomponent crystal formation is an effective strategy to improve bromhexine's poor solubility and bioavailability.
- The bromhexine-fumaric acid cocrystal offers enhanced physicochemical properties for potential therapeutic applications.
- Further research into bromhexine cocrystals could lead to improved drug delivery and efficacy.
Related Concept Videos
Halogenation of Alkenes
Consider the bromination of cyclopentene. Molecular bromine is polarized in the proximity of the π electrons of cyclopentene. An electrophilic bromine atom adds across the double bond, forming a cyclic bromonium ion intermediate.
Formation of Halohydrin from Alkenes
Electrophilic Aromatic Substitution: Fluorination and Iodination of Benzene
Electrophilic Aromatic Substitution: Chlorination and Bromination of Benzene
Factors Affecting Dissolution: Polymorphism, Amorphism and Pseudopolymorphism
Some polymorphic crystals possess lower aqueous solubility than their amorphous counterparts, leading to incomplete absorption. For instance, the oral suspension of Chloramphenicol, which...
VSEPR Theory and the Effect of Lone Pairs

