Development of a rapid on-field blood detection method using cerium oxide nanozymes

Abstract

Identification of body fluids is essential to any criminal investigation. Blood is the most commonly found evidence at crime scenes amongst body fluids, including semen, vaginal fluid, saliva and others. Preliminary and confirmatory tests are often used in traditional blood screening procedures. The catalytic interaction between a chemical, hydrogen peroxide and heme, which is present in blood, is the basis for the primary testing for blood. However, studies indicate that the screening tests often produce many false positives and the peroxide used in screening tests is hazardous to the DNA. Therefore, the present study posits a new safe, specific, sensitive and cost-effective screening method for blood detection utilising synthesised Cerium oxide nanoparticles (CeO2 nanozymes) to mitigate the toxic effect of H2O2. Findings of this study revealed that newly developed method for blood detection not only proves to be sensitive (up to the dilution factor of 1:1000 for 15 days) but also specific and did not show false positive for red colour stains. Further, this newly lab-based developed method was successfully translated into on-site/on-field paper-based detection system. This approach will provide rapid, sensitive, and cost-effective method to the forensic investigation which may enhance the pace of investigation procedure with minimize the chances of error.