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Nanobiosensor Arrays for On-Site Multiplexed Detection of Protein Markers to Identify Forensically Relevant Body Fluids

NCJ Number
310603
Date Published
2025
Length
38 pages
Abstract

The overarching goal of this project was to develop and validate a multiplexed, paper-based chemiresistive biosensorsystem for the rapid, selective, and on-site identification of multiple body fluids in crime scenes. Existing methods for body fluid identification are often time-consuming, costly, and confined to laboratory settings. This work addresses those limitations by introducing a low-cost, portable sensing platform capable of detecting protein biomarkers associated with blood, semen, saliva, urine, and sweat.

The system is built around a single-walled carbon nanotube (SWNT)-based bio-ink, which integrates the transducer (SWNT) and biorecognition element (antibody) for label-free electrical detection of biomarkers or analytes. The sensor response is recorded as a change in electrical resistance upon target binding (antigen-antibody reaction), allowing quantitative identification in minutes. The project progressed through four structured aims: developing lateral flow paper-based nanobiosensors for individual detection of each body fluid (Aim 1); demonstrating multiplexed detection using purified antigens (Aim 2); validating performance with artificial media and real biological samples (Aim 3); and exploring wireless integration for future field deployment (Aim 4).

The platform demonstrated high sensitivity, specificity, and reproducibility, with minimal cross-reactivity across a range of test conditions. Its paper-based construction and use of water-based inks make it cost-effective, environmental-friendly, and well-suited for point-of-use forensic applications. Overall, the project represents a significant advancement towards accessible, on-site forensic body fluid identification with potential applications in broader point-of-care diagnostics and environmental monitoring.

(Author abstract provided.)

Date Published: January 1, 2025