When DNA is absent, incomplete, or difficult to interpret, what other evidence can help forensic investigators make meaningful connections?

In this episode of Concentrating on Chromatography, David Oliva speaks with Dr. Candice Bridge of the University of Central Florida and the National Center for Forensic Science about the emerging field of forensic lubricant analysis.

Dr. Bridge explains how chemical residues from sexual lubricants can support sexual-assault investigations by helping connect a victim, suspect, condom wrapper, or crime scene—especially when a usable DNA profile is unavailable. She discusses why DNA is not always the “silver bullet” people expect, why preserving limited evidence is essential, and how forensic laboratories prioritize the least destructive analysis first.

The conversation also explores the analytical chemistry behind lubricant evidence:

• The chemical differences among water-, silicone-, oil-, and natural/edible-based lubricants
• Why personal-care products such as lotions and oils can complicate forensic interpretation
• The limitations of conventional GC-MS for high-mass polymers such as PDMS and PEG
• How DART-TOF mass spectrometry enables rapid screening of complex forensic samples
• Why extraction from cotton swabs and other evidence substrates remains a critical challenge
• How solvent polarity affects recovery of lubricant components
• How likelihood ratios, population studies, and retail-market data could help assess the rarity and evidentiary value of a recovered lubricant residue
• Practical advice for undergraduate students considering careers in forensic science and analytical chemistry

Dr. Bridge also shares why she chose an underdeveloped research area, what it takes to build a new forensic discipline, and why students should pursue socially important scientific questions—even when funding and established protocols have not yet caught up.

Guest: Dr. Candice Bridge
Host: David Oliva
Podcast: Concentrating on Chromatography

Follow the podcast for conversations on chromatography, mass spectrometry, forensic science, sample preparation, laboratory technology, and careers in analytical chemistry.