圆珠笔油墨字迹色痕的高效液相色谱分析方法

Analysis of Ballpoint Pen Inks′ Handwriting for the Forensic Differentiation with High Performance Liquid Chromatography

采用正交实验设计法从多种流动相体系中优选出了圆珠笔油墨字迹色痕的高效液相色谱分析条件。在此条件下分析了 10 5种市售的不同生产厂家和牌号蓝色圆珠笔油墨的字迹色痕 ,并依据有色成分的差异将这些同色油墨分成了 6大类 ,考察了纸张的影响因素及在该条件下分析结果的重现性和精密度 。

105 kinds of blue ballpoint pen ink handwriting were analyzed by high performance liquid chromatography. All these kinds of color ballpoint pen ink from different manufacturers were classified into six different categories according to disparities of their dyeing components. The crystal violet (C.I. 42555) is the chief dyestuff of all ballpoint pen inks. In this paper the orthogonal array method was used to select the optimum chromatographic condition. A Waters C-18 column (150 mm x 4.6 mm i.d., 5 mum) with a mobile phase of acetonitrile/1.25% acetic acid (60:40, V/V) were used at a flow rate of 1.0 mL/min. The optimum extraction solvent was acetonitrile/water(3:2, V/V) and the detection wavelength was 580 nm. The relative standard deviations were 2.0% (n = 5). This method provides useful information for the determination of the age of ballpoint pen ink handwriting.