Disposable MoS₂-Arrayed MALDI MS Chip for High-Throughput and Rapid Quantification of Sulfonamides in Multiple Real...

Area of Science:

• Analytical Chemistry
• Mass Spectrometry
• Materials Science

Background:

• Sulfonamides (SAs) are widely used antibiotics, and their residues in food pose significant health risks.
• Accurate and efficient detection methods are crucial for monitoring SA contamination in foodstuffs.
• Existing methods for SA analysis can be time-consuming and labor-intensive.

Purpose of the Study:

• To develop a novel disposable matrix-assisted laser desorption/ionization mass spectrometry (MALDI MS) chip for sulfonamide quantitation.
• To integrate immunoaffinity enrichment with the developed MALDI MS chip for enhanced sensitivity and specificity.
• To establish a high-throughput, rapid, and simultaneous method for detecting multiple sulfonamides in real food samples.

Main Methods:

• Fabrication of a disposable MALDI MS chip using molybdenum disulfide (MoS2) arrays on an indium tin oxide (ITO) glass slide.
• Development of an immunoaffinity enrichment technique using antibody-conjugated magnetic beads for targeted SA extraction.
• Quantitative analysis of sulfonamides using an internal standard (IS) pre-deposited on the MoS2 array, enabling analysis of 96 samples in 10 minutes.

Main Results:

• The MoS2-arrayed MALDI MS chip demonstrated comparable laser desorption/ionization (LDI) efficiency to commercial steel plates, serving as a viable disposable substrate.
• The developed method achieved a linear range of 0.5-10 ng/mL (R² > 0.990) for five sulfonamides.
• Successful quantification of sulfonamides in spiked pork, egg, and milk samples with good recoveries and repeatability, and detection in real foodstuffs.

Conclusions:

• The disposable MoS2-arrayed MALDI MS chip combined with immunoaffinity enrichment offers a high-throughput, rapid, and sensitive platform for sulfonamide analysis.
• This method simplifies experimental procedures and reduces analysis time, making it suitable for routine monitoring of antibiotic residues.
• The developed approach presents a promising tool for ensuring food safety by effectively detecting sulfonamide contamination.