A liquid chromatography method for quantifying caffeine dissolution from pharmaceutical formulations into colloidal,...

Area of Science:

• Analytical Chemistry
• Pharmaceutical Sciences

Background:

• Colloidal fat emulsions are increasingly used as biorelevant dissolution media.
• Accurate quantification of drugs in these complex media is essential for in vitro dissolution testing.

Purpose of the Study:

• To develop and validate a simple, rapid, and high-throughput high-performance liquid-chromatography (HPLC) method for caffeine quantification.
• To assess the method's applicability in biorelevant dissolution media, including Intralipid and various milk types.

Main Methods:

• HPLC analysis using a mobile phase of 0.1 M sodium acetate (pH 4.0) and acetonitrile (89.5:10.5, v/v) at 1 ml/min.
• Caffeine extraction via protein precipitation with 12% trichloroacetic acid followed by centrifugation.
• Validation of the method for recovery, limit of detection, linearity, precision, and accuracy.

Main Results:

• The method achieved rapid elution of caffeine and internal standard within 8 minutes.
• Caffeine recovery ranged from 75.4% to 100.6%, with good linearity up to 125 µg/ml.
• The method demonstrated high precision (<11.5% RSD) and accuracy (93.4-109.3%) in various fat emulsions.

Conclusions:

• The validated HPLC method is suitable for high-throughput quantification of caffeine in fat emulsions.
• The method can be effectively applied to in vitro dissolution tests comparing drug release kinetics from different formulations (e.g., extended-release vs. immediate-release).
• This analytical approach supports the use of fat emulsions as biorelevant dissolution media.