Inhibition assay method and device for detection of antibiotics

A self-contained test apparatus for microbial culture, growth inhibition, and detection of at least one antibiotic in a test sample, whereby the at least one antibiotic includes a first antibiotic from a first structural class and an antibiotic from another structural class or a second antibiotic from the first structural class, said test apparatus comprising:

• a) a vial at a one end of the test apparatus, the vial containing a microbial culture and a microbial receptor, the culture comprising a microbial species susceptible to the at least one antibiotic, the culture comprising:
• (i) agar, (ii) spores, (iii) nutrients, and a (iv) pH indicator, and the receptor characterized by its sensitivity to the first antibiotic from the first structural class and having been extracted from a bacteria with sensitivity to the first structural class,
• b) a test apparatus body, the body attached to both the vial and a cap, the body having a space in the center to receive a sampler, the sampler attached to the cap and configured to obtain the sample and to transfer into the vial the sample to be tested for antibiotics;
• c) a container, the container located within the vial and above the culture, the container comprising:
• (i) a cylinder having a one open end and another opposite open end,
• (ii) a membrane seal over the open ends to form a sealed compartment that is puncturable by the sampler, and
• (iii) an extraction reagent sealed within the sealed compartment, and
• wherein the sampler is used to obtain the sample and add the sample to the extraction reagent and to the culture, wherein the receptor selectively reduces test sensitivity to the first antibiotic of the first structural class without substantially reducing test sensitivity to the antibiotic from the another structural class or the second antibiotic from the first structural class to indicate the presence in the sample of the at least one antibiotic.