Benzalkonium in Nasal Spray Using Acclaim Surfactant Plus with Charged Aerosol Detection

Significance of the Topic

In pharmaceutical formulations such as nasal sprays, quantification of benzalkonium surfactants is essential due to their antimicrobial activity and impact on product safety.

Objectives and Study Overview

The primary goal was to efficiently separate and detect benzalkonium homologs in a commercial nasal spray using a surfactant-optimized UHPLC method coupled with charged aerosol detection.

Methodology and Instrumentation

• Column: Acclaim Surfactant Plus (3 µm, 3.0 × 150 mm)
• System: Dionex UltiMate 3000 RSLC
• Mobile phases: acetonitrile and 100 mM ammonium acetate (pH 5.2)
• Gradient: 25 %–80 % acetonitrile over 8–10 min, held to 20 min
• Flow rate: 0.6 mL/min; temperature: 30 °C; injection volume: 5 µL
• Detector: Corona ultra charged aerosol detector (gain=100 pA; filter=medium; nebulizer=20 °C)

Key Results and Discussion

The method delivered baseline resolution of major benzalkonium homologs with sharp, symmetrical peaks. Analysis time was under 20 min, demonstrating the column’s selectivity for cationic surfactants and stability under routine conditions.

Benefits and Practical Applications

• Rapid, reliable quantification for quality control of nasal sprays and other formulations
• Low column bleed and robust performance enable consistent routine analysis
• Single-run assessment of multiple homologs simplifies workflow in pharmaceutical laboratories

Future Trends and Opportunities

Advances may include higher sensitivity detectors, automation for high-throughput screening, and method transfer to other surfactant classes or dosage forms. Integration with mass spectrometry could further enhance specificity.

Conclusion

The optimized UHPLC–CAD approach on the Acclaim Surfactant Plus column provides a fast, reproducible platform for analyzing benzalkonium preservatives in nasal sprays, supporting regulatory compliance and product safety.