To evaluate the reproducibility of enz-PADs for the creatinine assay, 20 pieces of enz-PADs fabricated on the same day were used to perform assays with 5 mg dL1 and 20 mg dL1 of creatinine. The results showed that within-day precisions with coefficients of variation (CVs) of 8.82% and 6.86% were obtained for assays of 5 mg dL1 (n¼10) and 20 mg dL1 (n¼10) of creatinine, respectively. Between day precisions at 11.57% and 9.39% coefficients of variation (CVs) were obtained when evaluated with 5 mg dL1 and 20 mg dL1 of creatinine standard on three consecutive days (n¼30), respectively