In this study, we introduce a simple three-step workflow for a universally applicable RI system, to be used in GC×GC analysis of ignitable liquid residue (ILR) for arson investigations. The proposed RI system applies a combination of two well-established GC RI systems: non-isothermal Kovats (K) index in the first dimension and Lee (L) index in the second dimension. The proposed KLI RI system showed very good correlations when compared with predicted values and existing RI systems (r² = 0.97 in first dimension, r² = 0.99 in second dimension) and was valid for a wide range of analyte concentrations and operational settings (coefficient of variance (CV) < 1% in first dimension, < 10% in second dimension). Using the KLI RI, an ILR classification contour map was created to assist with the identification of ILR types within ASTM E1618. The contour map was successfully applied to neat fuels and a fire scene sample, highlighting the application to wildfire investigation. Standardizing the RI process and establishing acceptable error margins allows the exploration and comparison of comprehensive data generated from GC×GC analysis of ILRs regardless of location, time, or system, further enhancing comprehensive and tenable chemometric analyses of samples. Overall, the KLI workflow was inexpensive, quick to apply, and user-friendly with its simple 3-step design.

在这项研究中，我们为通用的RI系统介绍了一个简单的三步工作流程，该流程将用于可燃液体残留物（ILR）的GC×GC分析，以进行纵火调查。拟议的RI系统应用了两个公认的GC RI系统的组合：第一维的非等温Kovats（K）指数和第二维的Lee（L）指数。与预测值和现有RI系统相比，拟议的KLI RI系统显示出非常好的相关性（ 第一维度r ² = 0.97，r ² =在第二维上为0.99），并且适用于各种分析物浓度和操作设置（在第一维上变异系数（CV）<1％，在第二维上<10％）。使用KLI RI，创建了ILR分类等高线图，以帮助在ASTM E1618中识别ILR类型。等高线图已成功应用于纯净燃料和火场样本，突显了其在野火调查中的应用。通过对RI过程进行标准化并建立可接受的误差范围，可以探索和比较从ILR的GC×GC分析生成的综合数据，而无需考虑位置，时间或系统，从而进一步增强了样品的综合化学分析。总体而言，KLI工作流程价格低廉，易于应用，并且其简单的三步式设计易于使用。