Naked-eye detection of antibiotic resistance gene sul1 based on aggregation of magnetic nanoparticles and DNA amplification products

The continued spread of antimicrobial resistance is a global problem. In fact, the WHO has declared one top 10 public health threats facing humanity. Molecular methods offer faster means characterizing resistant strains than phenotypic drug susceptibility testing. We have developed molecular detection method that generates visible aggregates from DNA amplified products and functionalized magnetic nanoparticles. amplification procedure take less 2 h. this study we also investigated factors behind aggregation confirmed size padlock probe relevant parameter for efficiency. compared 92 69 nt long found latter to perform over 4 times better probe. This effect was related higher quantity produced by shorter Consequently, affects in positive way, thanks it, assay sensitivity achieved. Finally, using our method, could detect as little 1 amol antibiotic-resistance gene sul1 sample containing multiresistance plasmid. were able quantify amount plasmid through absorbance spectroscopy AC susceptometry. presented results form foundation future development an ultrasensitive cheap approach be used point care settings.