Aptamer-based fluorometric assay for direct identification of methicillin-resistant Staphylococcus aureus from clinical samples

Accurate and rapid identification of methicillin-resistant Staphylococcus aureus (MRSA) is of important clinical significance. In this study, a novel aptamer-based fluorometric assay was developed for detection of MRSA in clinical samples by coupling with immunomagnetic separation . The S. aureus cells in clinical specimens were enriched by magnetic separation. Following lysis by staphylococcal lysin , the PBP2a proteins were released from S. aureus cells and detected by the aptamer-based fluorometric assay. Without lengthy period of bacteria cultivation in the traditional susceptibility testing, this test has an overall testing time of only 2 h with the detection limit of 2.63 × 10 3 and 1.38 × 10 3  CFU/mL in PBS and spiked nasal swab, respectively. Since it is simple, rapid and sensitive, this method could be used for the detection of MRSA in various clinical samples.