Related Experiment Video
Updated: Nov 24, 2025

Self-Nanoemulsification of Healthy Oils to Enhance the Solubility of Lipophilic Drugs
Published on: July 27, 2022
Natural Plus Synthetic Hydrotropic Solubilization using Response Surface Methodology to Optimize the Solid Dispersion
Arun Saharawat1, Deepali1, Nidhi Nainwal1
1School of Pharmaceutical Sciences and Technology, Sardar Bhagwan Singh University, Balawala, Dehradun, Uttarakhand 248001,India.
Background:
Solubility/dissolution is said to be the key factor that influences the oral bioavailability of drug and is also the rate limiting step in formulation development.
Objective:
Hydrochlorothiazide (HCZ) is a BCS Class IV drug with low solubility and low permeability. The present work aimed to increase the solubility of hydrochlorothiazide using blends of natural and synthetic hydrotropes.
Methods:
Two hydrotropes one from natural (piperazine) and other from the synthetic origin (sodium benzoate) were selected for the formulation of solid dispersion (SD) of HCZ. Preliminary trial batches were prepared by considering the safe dose of both the selected hydrotropes i.e. sodium benzoate (SB) and piperazine (PP). A 32 full factorial design was opted for preparing the optimized solid dispersion of hydrochlorothiazide.
Results:
The quadratic models were found to be best fitted for the studied responses, which were percent solubility and in-vitro drug release. The results showed increased solubility and in-vitro drug release of HCZ solid dispersions as a function of increasing levels of both hydrotropes.
Conclusion:
In this work, it was concluded that the use of natural hydrotropes along with synthetic hydrotropes gave an effective and safe approach for the solubility enhancement of the HCZ.
Related Concept Videos
Bioavailability Enhancement: Drug Solubility Enhancement
Factors Affecting Dissolution: Particle Size and Effective Surface Area
Factors Influencing Drug Absorption: Pharmaceutical Parameters
Solubility
A solution is a homogeneous mixture composed of a solvent, the major component, and a solute, the minor component. The physical state of a solution—solid, liquid, or gas—is typically the same as that of the solvent. Solute concentrations are often described with qualitative terms such as dilute (of relatively low concentration) and concentrated (of relatively high concentration).
In a solution, the solute particles (molecules,...
In Vitro Drug Dissolution: Alternative Methods
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...

