Fingerprints have been used to identify suspects involved in criminal activity since the early 20th century and are now even used as a 'password' to access computers, mobile devices and buildings. The identification of fingermarks (the sweat-based material left behind when a fingertip comes in contact with a surface) has traditionally involved pattern-matching and establishing whether the ridge detail (the lines that make up the pattern) of a fingermark found at a crime scene matches to a suspect. Significant advances in analytical chemistry techniques over the last two decades has meant that our understanding of the chemistry of these fingermarks and what we can find out from them has increased dramatically. Here are some examples of the research in this area and how it could help with the investigation of a crime.

 Thinking Digital talk by Prof. Simona Francese (University of Sheffield) - "Fingerprints and lasers...your secrets in a touch":
Your Secrets In A Touch - Simona Francese (Links to an external site.)

Here are some articles about extracting information from someone's fingermark:

 Did the suspect pick up cocaine on their fingertips from handling a contaminated object (e.g. a banknote) or did they take cocaine?:
https://www.newscientist.com/article/2232622-a-fingerprint-can-show-if-someone-has-taken-cocaine-or-just-touched-it/ (Links to an external site.)

 Fingermarks could be used to check whether someone is taking their medication as required or not:
https://www.eurekalert.org/pub_releases/2019-11/uos-ftc110819.php