Improved Steroids Detection and Evidence for Their Regiospecific Decompositions Using Anion Attachment Mass...

Area of Science:

• Analytical Chemistry
• Forensic Science
• Mass Spectrometry

Background:

• Nonpolar anabolic steroids are challenging to detect using conventional mass spectrometry techniques due to their low polarity.
• Existing methods like electrospray ionization (ESI) and atmospheric pressure photoionization (APPI) often yield weak signals for these compounds.

Purpose of the Study:

• To investigate the use of anion addition as an ionization enhancement strategy for nonpolar anabolic steroids.
• To evaluate the effectiveness of fluoride anion attachment mass spectrometry (FA-MS) in improving detection limits and selectivity.

Main Methods:

• Samples of nonpolar anabolic steroids were analyzed using fluoride anion attachment mass spectrometry.
• Comparison of detection limits and spectral data with traditional ESI(+)/(-) and APPI(+) methods.
• Collision-induced decomposition (CID) studies were performed on fluoride adducts of specific steroids.

Main Results:

• FA-MS achieved significantly lower instrumental limits of detection (e.g., 10 ng/mL for fluoxymesterone-M) compared to ESI and APPI.
• CID spectra of fluoride adducts demonstrated regiospecific decomposition pathways, indicating selective attachment to hydroxyl groups.
• This selectivity offers potential for improved accuracy in selected reaction monitoring (SRM) experiments.

Conclusions:

• Fluoride anion attachment is a valuable technique for enhancing the detection of nonpolar anabolic steroids in mass spectrometry.
• The observed regiospecificity in CID fragmentation provides a basis for more selective and accurate quantification in doping control.
• FA-MS represents a promising advancement for forensic and analytical applications involving challenging steroid analytes.