Kirby-Bauer test

Grendahl and Sung [96] tested a simple, reliable, and inexpensive assay method for the quantitation of serum levels of miconazole and other imidazole drugs. This assay, which is similar to Kirby-Bauer test, was sensitive to 0.2 pg of drug/mL and linear from <0.2 to 10 pg/mL. Concentration of inoculum and agar depth in test plates was not as critical as the type of medium, amount of inoculum or type of drug used. 

The testing procedure involving colonized bacteria Pseudomonas aureus in the protocol was too challenging for the water-based dressing and resulted in unacceptable mortality of rats. In follow-up tests, FD C dyes were observed to penetrate the thickness of the dressing to the tissue, which means that the barrier was permeable to bacteria. Chlorhexidine added to the aqueous and polymer phase of the emulsion produced acceptable results in Kirby-Bauer tests, but not inoculation tests with bacteria on excised rats. 

The barrier dressings formed over agar plates and porcine tissue were successful. No Kirby-Bauer tests have been performed on excised rats to date. The dressing forms a water-impermeable barrier, is impermeable of FD C dyes, and materials with these properties are impermeable to dyes (see Figs. 2.11 and 2.12). 

Note 1 Kirby-Bauer Test - acceptable zone diameter (of inhibition) is greater than the control disk of 6 mm... 

The antibacterial activity of PPy-NTs Ag-NPs nanocomposites with different Ag-NPs concentrations investigated by Kirby-Bauer test have been presented in the Fig. 16. It has been observed that the antibacterial activity increases with the increase in Ag-NPs concentrations in the nanocomposites. Nanocomposites with 6 wt% of Ag-NPs exhibit zone of 18 and 21 mm against E. coli and S. aureus, respectively and increases up to 23 mm for 15 wt% of Ag-NPs against both the microorganisms (Table 6). In contrast, the antibacterial activity of pristine PPy-NTs... 

Fig. 16 Photograph images of the zone of inhibitions of PPy-NTs Ag-NPs nanocomposites with (a) 6 wt%, (b) 9 wt%, (c) 12 wt% and (d) 15 wt% of Ag-NPs by Kirby-Bauer test against i . coli and ii S. aureus bacteria...

Kirby-Bauer Plate Test (Disk Sensitivity Method)... 

The Kirby-Bauer technique (Black 2002) was used to test for antimicrobial activity... 

It is important to point out that although the caprylic acid/oleic acid emulsion demonstrated small, but measurable, antimicrobial activity in the liquid phase (Baker Suspension Test), and the Kirby-Bauer Plate test showed marginal antimicrobial... 

Antimicrobial testing was performed using the Kirby-Bauer Disk assay as described by Hendrix (1) and results summarized in Table 3. 

Once an organism has grown on culture, sensitivity testing can be performed to determine which antibiotics are the most effective.The most commonly used method, the Kirby-Bauer diffusion disc system, usually takes 48 hours to perform. Unfortunately, it can be inaccurate because of the lower concentrations of antibiotic on the test discs compared with levels that can be achieved in the cornea through topical application. In addition, some topical ocular preparations are not available on discs for sensitivity testing. 

Kirby-Bauer Disk-Diffusion Method and Modified Kirby-Bauer Susceptibility Test (a. 15)... 

MICs) of a drug for comparison with anticipated blood or tissue levels. The two most common methods of susceptibility testing are disk dilfusion (Kirby-Bauer) and broth dilution. For some bacteria (eg, gonococci, enterococci, H influenzae), a direct test for beta-lac-tamase can be substituted, since susceptibility patterns are identical for all strains except for the production of beta-lactamase. 

The agar diffusion method (Kirby—Bauer) is also sometimes used for the evaluation of antibacterial activity of textiles. This is a relatively quick and easily executed semiquantitative method to determine antibacterial activity of diffusible antimicrobial agents on treated textile material. The bacteria are grown in nutrient broth medium and after appropriate dilution (e.g., lOOx) from the culture, test organisms are swabbed over the surface of agar plates. Ten-millimetre-diameter disks of the test fabric and control fabric are then gently pressed onto the surface of the plate. The plates are then incubated at 37 °C for 18—24 h. The antibacterial activity of the fabrics is demonstrated by the diameter of the zone of inhibition in comparison to the control textile sample. 

NOTE 1 SECTION 35 is to be used to record disc sensitivities for clinical applications (eg., the methods of Bauer et. al., 1966, commonly referred to as Kirby-Bauer or Bauer-Kirby Methods). Other tests of antimicrobial sensitivity or resistance should be coded under SECTION 19/40.]... 

The ZOI test, also widely known as the Kirby-Bauer disk diffusion test, is a fast in vitro but semiquantitative test [169], The original purpose of this test was to replace the MIC test for small molecule antibiotic efficacy [169], Soon, this method was adopted and modified to evaluate antimicrobial efficacy of silver and polymeric devices with eluting antimicrobial agents [170], Conunonly used eluting antimicrobial agents are zinc salt/particles [171-173], silver salt/particles [173-177], and chlorhexi-dine [178,179], These antimicrobial agents can be compounded/blended into polyurethanes or coated/adsorbed on polyurethanes. 

Boyle VJ, Fancher ME, Ross RW. Rapid, modified Kirby-Bauer susceptibUity test with single, high-concentration antimicrobial disks. Antimicrob Agents Chemother 1973 3 418-24. 

The library of silver-NHC compounds has been greatly expanded due to the contributions of Tacke and coworkers (13a-21) [13-17] and Roland et al. (22a-25b) [18]. Compounds 13a-21 (Figure 6.1), all bearing the acetate ligand, were evaluated for their antimicrobial efficacy against S. aureus and . coli using a qualitative Kirby-Bauer disk-diffusion method. The imidazolium salt precursors, silver acetate, and the vehicle (dimethylsulfoxide) served as controls. The results of the tests were mixed, with a number of compounds having a weak... 

The following photos demonstrate the Kirby-Bauer bacterial resistance test as well as the ASTM E-1428-96 pink staining organism test. 

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