paperbagdude

Hi. My grandfather suffering from chronic respiratory issues has been gifted a lung exerciser/mucus loosening tool by my aunt. According to the user manual, the tool should be disassembled and suspended in a 20% solution of isopropanol every night to kill bacteria incubated over the day, but since the use of isopropanol can be expensive over time, I'm looking for a cheaper alternative. The tool is primarily made of polycarbonate in terms of chemical resistance to the potential solution. I have thought of a hypertonic solution of 5% sodium chloride or and unspecified concentration of diluted acetic acid, but I'm unsure of how effective these are in terms of proper overnight disinfection. I'd like to hear your thoughts and suggestions on this. Also, I don't want to loose my merit as a lab tech to my grandfather, so please provide some documentation or proof of how effective the solution actually is :-)