Identification of Unique Fragmentation Patterns of Fentanyl Analog Protomers Using Structures for Lossless Ion...

Area of Science:

• Forensic Chemistry
• Analytical Chemistry
• Mass Spectrometry

Background:

• The opioid crisis is exacerbated by novel fentanyl analogs and precursors that evade conventional detection methods relying on reference compound libraries.
• The absence of reference standards for new fentanyl variants hinders accurate identification and forensic analysis.

Purpose of the Study:

• To develop a reference-free analytical approach for identifying fentanyl and its analogs.
• To investigate the gas-phase structures and fragmentation patterns of fentanyls using advanced spectrometry techniques.

Main Methods:

• Utilized a combination of electrospray ionization (ESI), high-resolution ion mobility (IM) spectrometry, high-resolution mass spectrometry (MS), and higher-energy collision-induced dissociation (MS/MS).
• Analyzed a mixture containing nine fentanyls and a structurally similar compound (W-15).
• Examined the influence of water concentration in ESI solution on ion mobility distributions and MS/MS fragmentation.

Main Results:

• All analyzed fentanyls exhibited two distinct ion mobility distributions, yielding unique MS/MS fragmentation patterns.
• Fragmentation revealed that specific fragments predominantly originated from one of two distinct gas-phase structures (protomers) for each fentanyl.
• Increased water concentration in ESI solution shifted the relative intensities of these gas-phase structures, supporting their existence.

Conclusions:

• The distinct IM and MS/MS properties of fentanyls allow for their identification without the need for reference libraries.
• This reference-free method can differentiate fentanyls from other compounds, providing a valuable tool for law enforcement and first responders.
• The findings contribute to combating the emergence of new and potentially dangerous fentanyl variants.