In vitro production of viable bacteriophage in carbon dioxide and argon laser plumes

Both CO2 and argon laser ablation of an agar substrate containing high titres of bacteriophage phi X174 create plumes which disperse viable phage particles. Irradiances at the beam impact site ranged from 73 to 215 W/cm2 for the CO2 laser and from 40 to 227 W/cm2 for the argon laser. To increase the absorption of argon laser radiation, oxidized hemoglobin was added to the target material. Plume-borne viable phage were observed to be associated with particles large enough to settle out from the plume within 100 mm of the beam impact site. The ratio of the number of dispersed viable phage to the number of viable phage potentially dispersible by a single, 1-second laser exposure was on the order of 10(-6) to 10(-5).