Forensic chemistry is an important area of analytical chemistry. This field has been rapidly growing over the last several decades. Confirmation of the human origins of bloodstains is important in practical forensics. Current serological blood tests are destructive and often provide false positive results. Here, we report on the development of a nondestructive method that could potentially be applied at the scene for differentiation of human and animal blood using attenuated total reflection Fourier transform-infrared (ATR FT-IR) spectroscopy and statistical analysis. The following species were used to build statistical models for binary human–animal blood differentiation: cat, dog, rabbit, horse, cow, pig, opossum, and raccoon. Three other species (deer, elk, and ferret) were used for external validation. A partial least squares discriminant analysis (PLSDA) was used for classification purposes and showed excellent performance in internal cross-validation (CV). The method was externally validated first using blood samples from new donors of species used in the training data set, and second using donors of new species that were not used to construct the model. Both validations showed excellent results demonstrating potential of the developed approach for nondestructive, rapid, and statistically confident discrimination between human and animal blood for forensic purposes.

法医化学是分析化学的一个重要领域。在过去的几十年里，这个领域一直在迅速发展。确认血迹的人类来源在实际法医学中很重要。当前的血清学血液测试具有破坏性，并且经常提供假阳性结果。在这里，我们报告了一种非破坏性方法的开发，这种方法可能会在现场使用衰减全反射傅立叶变换红外 (ATR FT-IR) 光谱和统计分析来区分人类和动物血液。以下物种用于建立人-动物二元血液分化的统计模型：猫、狗、兔、马、牛、猪、负鼠和浣熊。其他三个物种（鹿、麋鹿和雪貂）用于外部验证。偏最小二乘判别分析 (PLSDA) 用于分类目的，并在内部交叉验证 (CV) 中表现出色。该方法首先使用训练数据集中使用的新物种供体的血液样本进行了外部验证，然后使用未用于构建模型的新物种供体进行了外部验证。两项验证均显示出出色的结果，证明了所开发方法在出于法医目的对人类和动物血液进行非破坏性、快速且统计可信的区分方面的潜力。其次使用未用于构建模型的新物种的供体。两项验证均显示出出色的结果，证明了所开发方法在出于法医目的对人类和动物血液进行非破坏性、快速且统计可信的区分方面的潜力。其次使用未用于构建模型的新物种的供体。两项验证均显示出出色的结果，证明了所开发方法在出于法医目的对人类和动物血液进行非破坏性、快速且统计可信的区分方面的潜力。