A: Record the IRabsorption spectrum,using a gas cell.The spectrum so obtained exhibits maxima only at the same wavelengths as that of a similar preparation of USP Perflubron RS.

B: The retention time of the major peak in the chromatogram of the test specimen,obtained as directed in the Assay,corresponds to that of USP Perflubron RS,similarly chromatographed.

Chromatographic system (see Chromatography á621ñ)—The gas chromatograph is equipped with a split injection port with a split ratio,range of 1:45to 1:100,a flame-ionization detector,and a 0.25-mm ×60-m column coated with a 1-µm film of phase G2.Hydrogen is used as the carrier gas.The chromatograph is programmed to maintain the column temperature at 35for 7minutes,then to increase the temperature at a rate of 20per minute to 185,and held at this temperature for 4.5minutes.The injection port is maintained between 200and 220and the detector at a temperature above 200.

Procedure— Inject a volume (about 0.2µL)of Perflubron into the chromatograph,record the chromatogram,and measure the areas of the peak responses.Calculate the percentage of each individual impurity in the portion of Perflubron taken by the formula: in which riis the peak response of the individual impurity,and rsis the sum of the responses of all the peaks:not more than 0.20%of any individual impurity is found.

Chromatographic system— Proceed as directed in the test for Chromatographic purity.

Procedure— Inject about 0.2µLof Perflubron into the chromatograph,record the chromatograms,and measure the areas of the peak responses.Calculate the percentage of C8BrF17in the portion of Perflubron taken by the formula: in which rUis the peak response for perflubron obtained from the test specimen,and rsis the sum of the responses of all of the peaks.