We report that an aqueous solution containing 1023 M adenosine triphosphate (ATP) and citrate-phosphate-dextrose-adenine (CPDA-1) can effectively replace transfusable human red blood cells in an in vitro Klun and Debboun bioassay system for evaluating chemicals for mosquito feeding-deterrent activity, using either Aedes aegypti or Anopheles stephensi. These species fed with similar avidity through collagen membrane covering aqueous 1023 M ATP plus CPDA-1 or red blood cells in CPDA-1 supplemented with ...