Abstract: An anti-microbial sensitivity test and testing stratum is disclosed for evaluating the sensitivity of different anti-microbial agents relative to identifiable microbial contaminants. The test stratum comprises a polymer such as poly(2-hydroxyethylmethacrylate) referred to as PHEMA, an organic solvent, such as polyethylene glycol (PEG), a hydrogen binding plasticizer, such as dimethylsulfoxide (DMSO), an an anti-microbial agent such as silver sulfadiazine, mafenide, nystatin, nitrofurazone, silver nitrate, bacitracin, gentamicin, amphotericin B, cesium nitrate, or other anti-microbial agents. The test includes positioning testing stratum of the type described, each having a different anti-microbial agent therein, on a sterile plate or on an agar substrate and spaced in fixed relationship to one another. The testing stratum are self adhering and remain fixed on a sterile plate, or on an applicator, even when the sterile plate, is inverted.