Aerosol containers half-life

Example 19.3 Figure 19.2 shows the size distribution of a sneeze as given by Lidwell (1967) (10s droplets per sneeze). Assuming each of the droplets contains one or more viable microorganisms with a virus survival half-life of 2 min, determine the viable aerosol concentration as a function of time, using Eq. 19.1. 

Recombinant a,-PI produced in yeast has also been clinically evaluated. This material is essentially identical to a -PI purified from human serum with respect to its protein sequence and its ability to inhibit neutrophil elastase however, it contains no carbohydrates. As such, one would suspect that the elimination rate following intravenous administration would be similar to that described for desialylated a -PI as described above [225]. In monkeys r-a,-PI disappeared from circulation with a half-life of 69 3 min. compared to a half-life of 2.4 0.2 days for a,-PI isolated from human serum [230], Rapid elimination following parenteral administration does not, however, preclude aerosol administration of the recombinant material. Aerosol administration of yeast-produced r-a,-PI, in doses ranging from 10 to 200 mg, resulted in a dose-dependent elevation of both antigenic recombinant a,-PI and EIC of BALF from apPI deficient individuals. Four hours after administration of a 200 mg dose of recombinant aj-PI, EIC was increased 40-fold over pre-treatment levels. Twenty-four hours post-dose, levels had declined to a 5-fold elevation relative to base-line levels. Modest increases of serum a,-PI levels were observed 24 h post-inhalation of the 200 mg dose [231], In this study, no adverse clinical reactions or evidence of sensitization to recombinant a,-PI were reported. 

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