Detection of Handwriting Forgery Made with Erasable Pens Using Desorption Electrospray Mass Spectrometry Imaging

Area of Science:

• Forensic Science
• Analytical Chemistry
• Mass Spectrometry

Background:

• Handwritten documents are vulnerable to fraud, including adulteration and forgery.
• Traditional methods for detecting document fraud can be time-consuming and may not always be conclusive.

Purpose of the Study:

• To investigate the application of Desorption Electrospray Ionization with Imaging (DESI-MSI) for detecting fraudulent alterations in handwritten documents.
• To evaluate DESI-MSI as a rapid and effective tool for forensic document analysis.

Main Methods:

• Simulated a fraud scenario involving the chemical erasure and replacement of original entries on white office paper.
• Utilized a DESI-MSI ion source coupled to a Q-Extractive mass spectrometer for direct analysis.
• Generated chemical images by mapping ion intensities to visualize the fraud process.

Main Results:

• DESI-MSI successfully identified and mapped the areas affected by the erasure and replacement process.
• Distinct ion intensity patterns revealed the sequence of fraudulent activities.
• The technique provided irrefutable chemical evidence of the document's adulteration.

Conclusions:

• DESI-MSI is a powerful and versatile technique for detecting fraud in handwritten documents, particularly those altered using chemical erasure methods.
• It offers a simple, fast, and reliable alternative to conventional forensic document examination techniques.
• The imaging capability of DESI-MSI provides clear, visual evidence crucial for forensic investigations.