Disclosed are antimicrobial releasing agents, methods of preparing the antimicrobial releasing agents, and entrained polymers containing antimicrobial releasing agents. The antimicrobial releasing agent is prepared with an acidified hydrophilic material with a pH below 3.5 as a carrier, an active compound, and a trigger. The entrained polymer of the invention releases an antimicrobial agent in gas form, such as ClO2, optionally over a range of concentration from 150 ppm to 1800 ppm per gram of the entrained polymer under certain tested conditions.