Microfluidic paper-based analytical aptasensor for fluorometric β-lactoglobulin determination

• DOI: 10.1016/j.microc.2024.110121
• Publication Date: 2024-02-10T02:47:41Z
• Authors: Inmaculada Ortiz-...; Andrey Ipatov; Elisa Barreiro-Docío; Alfonso Salinas-C...; Ignacio de Orbe-Payá; Luis Fermín Capit...; Marta Prado
• Keywords: Aptamer

Herein, we present a new luminescent-based analytical method for sensitive fluorometric determination of milk allergen, β-lactoglobulin (β-LG), in food products based on portable, low-cost, and easy-to-use microfluidic paper-based device (µPAD). For this purpose, the developed µPAD consisted β-LG specific aptamer immobilized cellulose disk, fluorescent Carbon Quantum Dots (CQDs) bioconjugated with its complementary oligonucleotide (DNA), which worked as label hybridization DNA (CQDs-DNA). In sample β-LG, preferentially binds to protein leads release CQDs-DNA. After washing µPAD, where is immobilized, detection achieved by fluorescence intensity decrease. An estimation concentration can be calculated thanks changes, that, photo taken using either digital camera or smartphone. The showed an excellent response range 1.8 500 ng/mL limit up 0.6 camera. Furthermore, was successfully applied samples such skimmed milk, crispy rice, cookies chocolate.