The broth dilution method involves subjecting the isolate to a series of concentrations of antimicrobial agents........the disks, creating a gradient of antibiotic concentration in the agar such that the highest concentration is .......................In addition there is a simple method for the rapid determination of antibiotic blood levels. With this method results are readily obtainable within 4 to 6 hr. The reported procedure is based upon determination of the highest of the patient's serum capable of inhibiting inhibiting dextrose fermentation by a standardized inoculum of a staphylococcus strain or of an Escherichia coli strain as compared to previously determined end-point elicited by prepared, set concentrations o different antibiotics dissolved in normal human serum For more information consult aem.asm.org Applied Microbiology Vol. 18, No. 4 pp. 601 - 603.

thank you sylvester for your help. it really help me a lots

Antibiotic susceptibility test (Kirby–Bauer test) can be performed in comparison with standard antibiotic of choice. The inhibition zone diameter can give an idea about the appx concentration of the antibiotic drug.

In serum with lambda max. after made standad curve for serum and antibiotic in vitro .

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