Specificity, sensitivity, and operability of RSID™-urine for forensic identification of urine: comparison with ELISA for Tamm-Horsfall protein.

In this study, the specificity, sensitivity, and operability of RSID™-Urine, a new immunochromatographic test for urine identification, was evaluated and compared with ELISA detection of Tamm-Horsfall protein (THP). Urine was successfully identified among other body fluids using RSID™-Urine and ELISA detection of THP. The detection limit of RSID™-Urine equated to 0.5 μL of urine; although the sensitivity of RSID™-Urine may be lower than that of ELISA detection of THP, it is thought to be sufficient for application to casework samples. However, results from RSID™-Urine must be interpreted with caution when the sample may have been contaminated with blood or vaginal fluid, because this might inhibit urine detection. The RSID™-Urine assay can be performed in just 15 min by dropping the extracted sample onto the test cassette. Therefore, RSID™-Urine should be an effective tool for the forensic identification of urine, in addition to ELISA detection of THP.