Ultrafast Analysis of Food Preservatives Using an Entry-Level Agilent 1290 Infinity II LC

Significance of the topic

The rapid and reliable detection of food preservatives is critical for quality control, regulatory compliance, and consumer safety. Ultrahigh-performance liquid chromatography (UHPLC) accelerates routine analyses by using small-particle columns under high pressure, enabling baseline separation in under one minute. Entry-level configurations that retain performance while reducing cost and footprint can democratize access to high-throughput methods in food testing laboratories.

Objectives and study overview

This study aimed to develop an ultrafast chromatographic method for seven common food preservatives, optimize it on an Agilent 1290 Infinity LC system, and then transfer it to an entry-level Agilent 1290 Infinity II LC configuration. Performance metrics—including run time, resolution, repeatability, linearity, limits of detection (LOD), and limits of quantification (LOQ)—were compared between the two systems.

Methodology and instrumentation

Chromatographic separation was carried out using a ZORBAX Eclipse Plus C18 RRHD column (2.1 × 50 mm, 1.8 µm) at 60 °C. The mobile phase consisted of water with 20 mM ammonium formate (pH 4.4) (A) and acetonitrile (B) at a flow rate of 1.9 mL/min. A rapid gradient increased from 8 % B to 60 % B in 0.1 min, held for 0.4 min, then to 98 % B at 0.6 min. Detection was performed at 254 nm.

Used instrumentation in entry-level Agilent 1290 Infinity II LC:

• Flexible Pump (G7104A)
• Vialsampler with integrated cooler and column compartment (G7129B Option 100 and Option 063)
• Variable Wavelength Detector with 10 mm flow cell (G7114B Option 018)

Method development and initial evaluation were performed on an Agilent 1290 Infinity LC equipped with quaternary pump (G4204A), autosampler (G4226A), column thermostat (G1330B), thermostatted column compartment (G1316C), and VWD (G1314E). Software: Agilent OpenLAB CDS ChemStation C.01.07 SR1.

Main results and discussion

Both systems achieved baseline separation of benzoic acid, sorbic acid, methyl-, ethyl-, propyl-, butylparaben, and butylated hydroxyanisole in under 0.6 min. On the Infinity LC, retention time (RT) RSDs were below 0.09 % and peak area RSDs under 0.18 %. Transfer to the Infinity II LC yielded similar or improved precision (RT RSDs < 0.07 %, area RSDs < 0.18 %) and slightly higher resolution (minimum Rs = 1.9). Calibration curves (1.56–200 ng/µL for most analytes; 0.04–5 ng/µL for sorbic acid) showed correlation coefficients ≥ 0.999 on both systems. LODs were below 0.5 ng and LOQs below 1.7 ng for all except butylated hydroxyanisole (LOQ ≈ 17 ng).

Benefits and practical applications

• High throughput: complete analysis in 0.6 min accelerates large sample batches.
• Excellent precision and sensitivity: RSDs below 0.2 % and sub-ng LODs enable trace-level quantification.
• Cost-effective entry-level configuration: compact design and lower investment while matching high-end performance.
• Flexibility: modular Infinity II components can be upgraded to add advanced features (e.g., dual-needle injection, spectral detectors).

Future trends and opportunities

Continued miniaturization and integration of UHPLC systems will further reduce solvent consumption and footprint. Automation of sample preparation and data processing will enhance lab productivity. Expansion to multi-analyte assays, coupling with mass spectrometry, and machine-learning–driven method optimization promise even broader applications in food safety, environmental monitoring, and pharmaceutical quality control.

Conclusion

An entry-level Agilent 1290 Infinity II LC configuration delivers ultrafast, high-precision analysis of seven food preservatives comparable to a high-end 1290 Infinity LC system. This demonstrates that cost-sensitive laboratories can adopt UHPLC technology without sacrificing performance, with straightforward upgrade paths for future needs.

Reference

1. The LC Handbook, Agilent Technologies Primer, publication number 5990-7595EN, 2016.
2. Agilent 1290 Infinity with ISET, Agilent Technologies User Manual, publication number G4220-90313, 2014.