Continuous dissolution rate determination as a function of the pH of the medium

Area of Science:

• Pharmaceutical Sciences
• Drug Delivery Systems
• Physical Pharmacy

Background:

• Dissolution testing is crucial for evaluating drug release from dosage forms.
• Modifying dissolution media properties, such as pH, can provide deeper insights into drug release mechanisms.
• Accurate simulation of physiological conditions during dissolution studies is essential for predicting in vivo performance.

Purpose of the Study:

• To develop and validate a method for dynamically altering the pH of dissolution media.
• To assess the dissolution rates of various timed-release formulations across different pH values.
• To establish a versatile tool for pharmaceutical formulation development and quality control.

Main Methods:

• A novel method utilizing compressed, fully soluble alkaline powders was employed to adjust medium pH.
• Dissolution rates of commercial and experimental timed-release tablets/capsules were measured.
• Studies were conducted at physiologically relevant pH values (1.1, 2.4, and 7.4).

Main Results:

• The developed method successfully enabled pH variation during dissolution rate studies.
• Dissolution profiles of timed-release dosage forms were characterized at distinct pH levels.
• The system demonstrated applicability for simulating varied physiological conditions.

Conclusions:

• The pH-varying dissolution system is a valuable tool for correlating in vitro release with in vivo bioavailability.
• This method can effectively differentiate between alternative drug formulations during development.
• It serves as a robust quality control procedure for sustained-release dosage forms.