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Covert thermal barcodes based on phase change nanoparticles

NCJ Number
Scientific Reports Volume: 4 Dated: 2014 Pages: 5170
B. Duong; H. Liu; L. Ma; M. Su
Date Published
1 page

Since there is an unmet need to develop covert barcodes that can be used to track-trace objects and authenticate documents. This article describes a new nanoparticle-based covert barcode system, in which a selected panel of solid-to-liquid phase change nanoparticles with discrete and sharp melting peaks is added in a variety of objects such as explosive derivative, drug, polymer and ink. 


This method has high labeling capacity owing to the small sizes of nanoparticles, sharp melting peaks, and large scan range of thermal analysis. The thermal barcode can enhance forensic investigation by its technical readiness, structural covertness, and robustness. (publisher abstract modified)