[Magnet-supported chemiluminescent detection for amplified mecA gene of methicillin-resistant Staphylococcus aureus]

A method of chemiluminescent detection for mecA gene of methicillin-resistant S. aureus amplified by polymerase chain reaction, was developed. The senseprimer was biotinylated at 5'-end, and an oligonucleotide probe, complementary to the senseprimer, was labeled with acridinium ester at 5'-end. Template DNA was obtained from colonies of S. aureus cultured on blood agar. Polymerase chain reaction product was hybridized with the probe and was separated using streptavidin-coated magnetic microparticles in magnetic field. The pellet was washed by decantations, and was measured for chemiluminescence in an automatic luminescence reader. For reference, drug sensitivity and presence of mecA gene were tested by dilution method and electrophoresis of polymerase chain reaction product, respectively, for each colony studied. Results showed that methicillin-resistant S. aureus (n = 44) and methicillin-susceptible S. aureus (n = 19) can be successfully differentiated by chemiluminescence measurement. This method is specific, rapid, and suitable for handling a large number of samples.