Derivatization-Enabled Detection of Formalin From Preserved Tissues Using Coated Blade Spray Mass Spectrometry

Area of Science:

• Natural History Collections
• Analytical Chemistry
• Molecular Biology

Background:

• Formalin-fixed specimens are valuable but formaldehyde poses genomic and safety challenges.
• Formaldehyde causes DNA damage and crosslinking, hindering molecular analyses.
• Existing detection methods are often invasive or slow.

Purpose of the Study:

• To develop a rapid, minimally invasive method for formaldehyde detection in preserved specimens.
• To assess the utility of coated blade spray mass spectrometry (CBS-MS) for this purpose.
• To characterize preservation chemistry in fluid-stored natural history samples.

Main Methods:

• Developed a coated blade spray mass spectrometry (CBS-MS) workflow.
• Utilized on-blade derivatization with 2,4-dinitrophenylhydrazine (2,4-DNPH).
• Employed a 3D-printed multiblade holder for sequential analysis of 12 specimens.

Main Results:

• Successfully detected formaldehyde in formalin-fixed mammal specimens.
• Identified formaldehyde in archival fruit bat specimens previously recorded as alcohol-preserved.
• Observed variations in signal intensity and visual evidence of paraformaldehyde.

Conclusions:

• The CBS-MS approach provides an efficient and minimally invasive strategy for formaldehyde detection.
• This method aids in characterizing preservation chemistry in fluid-stored natural history collections.
• The findings support improved handling and molecular analysis of historical specimens.