26 May Electromembrane Extraction and LC-MS/MS Analysis of Tetracyclines in Complex Samples

I would like to thank Anne Oldeide Hay and Frederik André Hansen from the Department of Pharmacy, University of Oslo, for sharing their paper “Electromembrane extraction of tetracyclines in foods and human plasma prior to LC-MS/MS analysis: Impact of sample matrix on extraction performance,” posted in the Advances in Sample Preparation open-access journal.
I found the application particularly interesting and insightful in highlighting the advantages of using electromembrane extraction (EME).

Here are some key insights highlighted directly from the paper:

Tetracycline antibiotics are widely used in agriculture and medicine, meaning trace residues can end up in food and biological samples. Detecting them isn’t easy—milk, eggs, honey, and blood are all chemically “messy,” and traditional lab methods can be slow, wasteful, and complicated.

This paper shows how electromembrane extraction (EME) offers a simpler and greener way to prepare samples before LC-MS/MS analysis.

What makes this approach different (and easier):

• One simple step instead of many:Traditional methods often require multiple clean-up steps. EME combines extraction and clean-up into a single step eliminating centrifugation, evaporation, and reconstitution.
• Much less chemical waste: Uses tiny amounts of solvent compared to common techniques that rely on large volumes of organic chemicals.
• Highly selective clean-up = better data: proteins, lipids, and salts remain behind—improving LC-MS/MS robustness and reducing ion suppression.
• Works across very different samples: The method was successfully applied to milk, egg white, honey, and human plasma.
• Designed with sustainability in mind: The method was formally evaluated using a green chemistry tool (AGREEprep score: 0.64) and scoring well for low waste and efficiency. Outperforming many conventional approaches

What the researchers showed:

Tetracyclines could be measured accurately and reliably in all tested samples
The method detected very low levels, well below regulatory limits for food safety
Matrix-specific optimization is essential (milk vs. honey vs. plasma) pH and extraction time varied by matrix, while voltage was largely matrix-independent
Tetracyclines extract far more efficiently as positively charged species, this is a key lesson for future method development
Why this matters
Compared to commonly used sample preparation methods SPE, LLE, PP, and even MIP-based approaches, EME is simpler, cleaner, and more environmentally friendly—without sacrificing performance. That makes it especially attractive for routine food safety testing and bioanalysis.

If you work in food safety, bioanalysis, or LC-MS/MS method development, this paper is worth reading.

Please also refer to the following for more information on Electromembrane Extraction (EME), as well as the application database https://how-to-eme.com/.