DNA is often used as a tracer in both environmental fluid flow characterization and in material tracking to avoid counterfeiting and ensure transparency in product value chains. The main drawback of DNA as a tracer is its limited stability, making quantitative analysis difficult. Here, we study length‐dependent DNA decay at elevated temperatures and under sunlight by quantitative PCR and show that the stability of randomly generated DNA sequences is inversely proportional to the sequence length. By quantifying the remaining DNA length distribution, we present a method to determine the extent of decay and to account for it. We propose a correction factor based on the ratio of measured concentrations of two different length sequences. Multiplying the measured DNA concentration by this length‐dependent correction factor enables precise DNA tracer quantification, even if DNA molecules have undergone more than 100‐fold degradation. © 2018 American Institute of Chemical Engineers AIChE J, 65: 40–48, 2019

中文翻译：

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长度依赖性DNA降解动力学模型：DNA示踪剂浓度测量中的衰减补偿

在环境流体流动表征和材料跟踪中，DNA经常被用作示踪剂，以避免伪造并确保产品价值链的透明度。DNA作为示踪剂的主要缺点是其有限的稳定性，使定量分析变得困难。在这里，我们通过定量PCR研究了高温和日光下依赖于长度的DNA衰变，并表明随机生成的DNA序列的稳定性与序列长度成反比。通过量化剩余的DNA长度分布，我们提出了一种确定衰变程度并加以考虑的方法。我们基于两个不同长度序列的实测浓度之比提出校正因子。即使将DNA分子降解了100倍以上，也可以将测得的DNA浓度乘以该长度相关的校正因子，从而进行精确的DNA示踪剂定量。©2018美国化学工程师学会AIChE J，65：40–48，2019