“Green” and Ultrafast Method for Determination of Soft Drink Ingredients on the Acclaim C18 RSLC Column

Significance of the topic

Soft drinks are consumed worldwide, making routine quality control of sweeteners and preservatives essential to safeguard public health and maintain product consistency. High-throughput methods that minimize toxic solvents and analytical time support more sustainable and cost-effective testing.

Objectives and study overview

This study aimed to develop an ultrafast, environmentally friendly liquid chromatography method to separate and quantify seven common soft drink additives. Key goals included replacing acetonitrile with ethanol, reducing analysis time to under 2 minutes, and maintaining reliable detection of all target compounds.

Methodology and instrumentation

The approach employs a sub-2 µm C18 column heated to 50 °C to lower mobile phase viscosity and maintain manageable backpressure. A binary gradient between 10 mM ammonium acetate buffer (pH 5) and 50% ethanol containing 10 mM ammonium acetate achieves separation in 1.4 minutes. Detection is performed by UV absorbance at 230 nm, switching to 214 nm to suppress interference near acesulfame-K. Samples are simply sonicated to remove dissolved CO2 before injection.

Used instrumentation

• LC system: UltiMate 3000
• Column: Acclaim RSLC C18, 2.2 µm, 3.0 × 50 mm
• Detector: UV with wavelength switching (230 nm to 214 nm)

Main results and discussion

Under optimized conditions, seven additives (acesulfame-K, sodium saccharin, aspartylphenylalanine, benzoic acid, caffeine, potassium sorbate, and aspartame) were baseline-separated within 1.4 min, yielding a throughput of about 20 samples per hour. Replacing acetonitrile with ethanol plus heating the column effectively reduced solvent toxicity and backpressure while preserving chromatographic performance. Wavelength switching further improved selectivity by minimizing spectral overlap.

Benefits and practical applications

• High sample throughput meets the demands of busy quality control laboratories.
• Green solvent choice and reduced analysis time lower environmental impact and operational costs.
• Minimal sample preparation streamlines routine soft drink additive assays.

Future trends and opportunities

Further developments may include coupling this rapid method with mass spectrometry for enhanced sensitivity and confirmation, automating sample handling for continuous monitoring, exploring alternative bio-based solvents, and extending the protocol to other beverage and food matrices.

Conclusion

The presented green and ultrafast LC method provides a robust, high-throughput solution for quantifying key soft drink additives, aligning analytical efficiency with sustainability objectives.

Reference

Dionex Corporation. Green and Ultrafast Method for Determination of Soft Drink Ingredients on the Acclaim C18 RSLC Column. Application Note, 2009.