Development of a Novel Aptamer for the Detection of Staphylococcal Enterotoxin Type C

Staphylococcal enterotoxin C (SEC) is a significant cause of food poisoning and is also implicated in conditions like toxic shock syndrome and atopic dermatitis. As SEC is heat-resistant and survives pasteurization, rapid and sensitive detection methods are essential for food safety monitoring. This study aimed to isolate high-affinity single-stranded DNA (ssDNA) aptamers specific to SEC as a novel diagnostic tool. Aptamers were selected using the Systematic Evolution of Ligands by Exponential Enrichment (SELEX) process, followed by evaluation via Enzyme-Linked Apta-Sorbent Assay (ELASA) and Surface Plasmon Resonance (SPR). From the candidate pool, Aptamer 2 demonstrated high specificity for SEC with a dissociation constant (KD) of 3.1 × 10⁻⁸ M. The limit of detection (LOD) for SEC using this aptamer was 0.34 nM. Our findings indicate that the selected aptamer can be effectively incorporated into an ELASA-based detection system, a repeatable, sensitive, and specific method for measuring SEC in real samples.