A Novel TLC-IA Approach for Forensic Differentiation of Fountain Pen Inks Using RGB Profiling | Chapter 9 | Science and Technology: Developments and Applications Vol. 10

Forensic science uses scientific methods or expertise to investigate criminal activities or analyse evidence that may be presented in a court of law. This article intends to present a novel and rapid technique for distinguishing inks on disputed papers. Ten blue fountain pen inks of two different types(bottle and refill) in differentbrands were acquired from the local market to create the collection and to beanalysed in the study. The separation of ink components was conducted using thin-layer chromatography (TLC). TLC investigations were conducted with Merck (Darmstadt, Germany) 20 cm x 20 cm silica gel 60 TLC plates without fluorescent indicators. The data was acquired by developing specialised image analysis software to assess thin-layer chromatograms (TLC-IA). This study marks Turkey’s inaugural application of TLC-IA to analyse fountain pen inks, employing RGB profiles for ink differentiation. This work represents the inaugural investigation into fountain pen inks, employing TLC-IA with RGB analysis for ink differentiation. The ink spot was removed from the document with methanol and isolated by thin-layer chromatography utilising a plastic sheet coated with silica gel 60, devoid of fluorescent indicator, employing a mobile phase composed of ethyl acetate, ethanol, and water in a ratio of 70:35:30 (v/v/v). A novel software was developed to differentiate fountain pen inks based following the development of the chromatogram, the chromatograms were digitised using a standard office scanner, and the intensity profiles of RGB attributes along the development line of each sample were generated and analysed with bespoke software. The RGB profiles of fountain pen inks from different manufacturers exhibited markedly varied patterns in most instances. Normalising RGB profiles facilitates a uniform comparison of colour values among various ink samples. Standardising RGB values to a range of 0–1 enhances the distinction among ink formulations.. In this analysis, darker colours on the heatmap represented higher similarity values between the samples. The study revealed that b 06, b 07, and b 08 were highly like one another across all visual methods—similarity matrix, normalised RGB profiles, and 3D scatter plots—while b 10 exhibited consistently low similarity to other samples, particularly b 04 and b 05. In conclusion, the importance of thin-layer chromatography (TLC) with RGB detection in forensic science lies in its ability to efficiently separate and visually analyse complex mixtures, such as inks or drugs, providing valuable evidence in investigations.

 

This pioneering work in Turkey facilitates the forensic utilisation of TLC-IA for ink

analysis, notably focussing on fountain pen inks for the first time.

 

 

Author (s) Details

Ozlem Simsek
Chemical Engineering Department, Faculty of Engineering and Natural Sciences, Uskudar University, Istanbul, Turkey and Graduate School of Addiction and Forensic Sciences, Uskudar University, Istanbul, Turkey.

 

S. Selim Seker
Electrical-Electronics Engineering Department, Faculty of Engineering and Natural Sciences, Uskudar University, Istanbul, Turkey and Electrical and Electronics Engineering Department, Bogazici University, Istanbul, Turkey.

 

Please see the book here:- https://doi.org/10.9734/bpi/stda/v10/5132