Integration of Bi2Te3 nanosheets with laser desorption/ionization mass spectrometry for sensitive glucose detection in soft drinks

Abstract

Accurate and sensitive detection of small biomolecules like saccharides in foods and beverages remains challenging due to the difficulty of their ionization and the interferences of the fragments derived from conventional organic matrices in laser desorption/ionization mass spectrometry (LDI-MS). Here, we present a methodology based on a Bi₂Te₃ nanomatrix for LDI-MS, enabling the rapid, specific, and sensitive detection of saccharides such as glucose, ¹³C-glucose, trehalose, maltotetraose, and maltohexaose. The Bi₂Te₃ nanomatrix demonstrated efficient analytical performance compared to traditional organic matrices (CHCA and DHB) by reducing spectral interferences and enhancing detection specificity and sensitivity. A strong linear response (R² = 0.9925) for glucose quantification was achieved, with a low limit of detection (LOD) of 0.25 μg mL⁻¹ (1.39 pmol). This method was validated through glucose quantification in three commercial soft drinks: one sugar-labeled (soft drink-1) and two sugar-free (soft drinks 2 and 3). The glucose concentrations were 11.11%, 0.01%, and undetectable, respectively, with corresponding recovery rates of 107.52%, 73.04%, and 79.66%. This study provides insights for developing advanced LDI nanomatrices, designed for the specific and sensitive detection of small biomolecules in food and beverage products.