Printed barcode lacks distributability as each barcode associated with sample cannot be divided when multiple copies of the same barcode are needed for forensic analysis. This article reports a metamorphic barcode with desired distributability to label objects (liquids or solids) in a covert and high-fidelity manner using polymer microdots containing a panel of phase change nanoparticles (low melting point metal or alloy). The microdots can be made with photolithography at large quantity or serial laser fabrication and have unique serialization numbers based on the melting characteristics of nanoparticles. The microdots can be distributed evenly in liquid or attached on various location of an object and decoded with differential scanning calorimeter. Incorporation of magnetic nanoparticles allows facile collection of polymer microdots with a magnet. The microdots are non-toxic and stable over one year without losing coding information and have higher large labeling capacity than other covert barcode systems.

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基于光刻定义的微点结合相变材料纳米粒子的变形条码

印刷条码缺乏可分发性，因为当法医分析需要同一条码的多个副本时，无法分割与样本相关的每个条码。本文报告了一种具有所需分布性的变质条形码，使用包含一组相变纳米粒子（低熔点金属或合金）的聚合物微点以隐蔽和高保真方式标记物体（液体或固体）。微点可以用光刻法大量制造或连续激光制造，并根据纳米粒子的熔化特性具有唯一的序列号。微点可以均匀分布在液体中或附着在物体的不同位置，并用差示扫描量热仪进行解码。磁性纳米粒子的结合允许使用磁铁轻松收集聚合物微点。微点无毒且稳定超过一年，不会丢失编码信息，并且比其他隐蔽条码系统具有更高的大标签容量。