TLC plate micro-extractor versus TLC-MS Interface: A comparative study on the extraction of non-steroidal anti-inflammatory drugs from milk as a model of a complex matrix.

This study evaluates a new approach for isolating analytes from thin-layer chromatography (TLC) plates, called the TLC plate micro-extraction (TLC-μE) technique, with a focus on non-steroidal anti-inflammatory drugs (NSAIDs). The performance of the TLC-μE device was compared to the commercially available TLC-MS Interface, with both approaches optimised for extraction conditions. Results demonstrate that TLC-μE offers superior extraction efficiency, reduces the risk of cross-contamination, and lowers operational costs. It aligns with green chemistry principles by requiring minimal solvent consumption and operates without electricity or a gas supply, making it suitable for use outside a standard laboratory setting. For methanolic samples, the peak areas for NSAIDs extracted using TLC-μE were more than double those obtained with the TLC-MS Interface under similar conditions. The application of the TLC-μE device for samples with complex matrices was performed by extracting drugs from fortified milk samples. HPLC analysis of the extracts obtained confirmed that TLC-μE demonstrated an average recovery increase of approximately 32.5 % compared to the TLC-MS Interface. These findings suggest that TLC-μE is a promising alternative for integrating TLC with instrumental analysis techniques. Future research will focus on expanding its applicability to a broader range of analytes and matrices.