Fast Quantitative Analysis of Aminoglycoside Antibiotic Residues in Meat, Eggs and Milk and Identity Confirmation with MRM Spectrum Mode

Significance of the topic

Residues of aminoglycoside antibiotics in meat, eggs, and milk pose health risks due to their oto- and nephrotoxicity and high tissue affinity. Regulatory bodies enforce maximum residue limits (MRLs) to safeguard consumers, requiring sensitive, rapid analytical methods for routine screening and confirmation of these highly polar compounds.

Study objectives and overview

This study aimed to establish a fast, quantitative workflow for detecting multiple aminoglycosides in various animal-derived foods, using hydrophilic interaction liquid chromatography coupled to triple quadrupole mass spectrometry (HILIC-LC-MS/MS). A secondary acquisition mode employing multiple reaction monitoring (MRM) spectrum ensures unambiguous identity confirmation without changing chemistry.

Methodology and instrumentation

Sample Preparation

• Grind 5 g of meat (beef, pork, chicken breast, chicken liver) or milk.
• Add ribostamycin as internal standard.
• Perform two extractions with acidic buffer.
• Purify extracts via weak-cation exchange and dilute fivefold.
• Inject 5 µL into the LC-MS/MS system.

Chromatography and Detection

• HILIC gradient of acetonitrile and ammonium formate buffer, 4.5 min cycle.
• Quantitative acquisition: two MRM transitions per analyte.
• Confirmation mode: extended gradient, 15 MRM transitions, MRM spectrum creation.

Instrumentation

• Nexera X2 UHPLC system.
• LCMS-8060 triple quadrupole mass spectrometer.
• LabSolutions Insight v.3.1 with Screening option for data processing.

Results and discussion

Calibration ranges were set between 10 % and 150 % of the applicable MRL or default 10 µg/kg for non-regulated analytes, using seven concentration levels with 85–115 % accuracy. Recoveries across meat and milk ranged from 70 % to 120 %, and repeatability (%RSD) stayed below 20 %. The MRM spectrum library search yielded high identification confidence—for example, dihydrostreptomycin scored 95 against streptomycin’s 51 in a spiked milk sample.

Benefits and practical applications

The developed method package delivers rapid, sensitive quantitation without ion-pairing reagents or matrix-matched calibrations. It is applicable to diverse food matrices and integrates both fast MRM quantitation and detailed spectrum-based confirmation in a single workflow, enhancing laboratory throughput and regulatory compliance.

Future trends and possibilities

Advances may include expanded compound libraries for broader veterinary drug screening, integration with high-resolution mass spectrometry for greater selectivity, on-site or inline screening platforms, and fully automated batch processing with real-time library matching to accelerate decision making in QA/QC environments.

Conclusion

Shimadzu’s HILIC-LC-MS/MS Method Package provides a robust, accurate, and efficient approach for simultaneous quantitation and confirmation of aminoglycoside residues in food matrices, supporting regulatory monitoring and ensuring consumer safety.