Principle
The Etest is basically an agar diffusion method.
The Etest utilises a rectangular strip that has been impregnated with the drug to be studied. A lawn of bacteria is spread and grown on an agar plate, and the Etest strip is laid on top; the drug diffuses out into the agar, producing an exponential gradient of the drug to be tested. There is an exponential scale printed on the strip. After 24 hours of incubation, an elliptical zone of inhibition is produced and the point at which the ellipse meets the strip gives a reading for the minimum inhibitory concentration (MIC) of the drug.
Read more about this topic: Epsilometer Test
Famous quotes containing the word principle:
“I often wish for the end of the wretched remnant of my life; and that wish is a rational one; but then the innate principle of self-preservation, wisely implanted in our natures, for obvious purposes, opposes that wish, and makes us endeavour to spin out our thread as long as we can, however decayed and rotten it may be.”
—Philip Dormer Stanhope, 4th Earl Chesterfield (1694–1773)
“Help thyself: then everyone will help thee too. Principle of Christian charity.”
—Friedrich Nietzsche (1844–1900)
“Why does philosophy use concepts and why does faith use symbols if both try to express the same ultimate? The answer, of course, is that the relation to the ultimate is not the same in each case. The philosophical relation is in principle a detached description of the basic structure in which the ultimate manifests itself. The relation of faith is in principle an involved expression of concern about the meaning of the ultimate for the faithful.”
—Paul Tillich (1886–1965)