Sample Preparation for MALDI-TOF Mass Spectrometry of Model Prebiotic Reactions in Simulated Ocean World Environments

TL;DR

This paper explores methods to prepare salty ocean world samples for mass spectrometry to study prebiotic chemistry.

Contribution

The study introduces optimized sample preparation techniques for analyzing saline prebiotic reactions using MALDI-TOF MS.

Findings

C18 ZipTips paired with DHB matrix worked best for MALDI-TOF MS analysis.

On-plate desalting with CHCA matrix also proved effective for saline solutions.

The methods enable low-volume sample preparation for prebiotic studies.

Abstract

The prebiotic potential of ocean worlds such as Europa
and Enceladus,
while not well constrained, is vital in the search for potential life
elsewhere. To better understand this potential, laboratory studies
provide experimental insight into the chemical environment(s) of ocean
worlds and any constraints to hold prebiotically relevant systems.
However, simulated ocean world solutions present a technical challenge
for analytical techniques such as mass spectrometry (MS), as the high
saline content required for simulating ocean world environments results
in ion suppression and reduced sensitivity. Here, we compare three
sample preparation techniques, C4 ZipTips, C18 ZipTips, and on-plate
washing, for matrix-assisted laser desorption/ionization –
time-of-flight (MALDI-TOF) MS of saline solutions similar to environments
expected in ocean worlds. We determined that using C18 ZipTips was
optimal when paired with 2,5-dihydroxybenzoic acid (DHB) matrix, whereas
on-plate desalting was optimal when paired with α-cyano-4-hydroxycinnamic
acid (CHCA) matrix. The methodology described here presents simple,
low-volume sample preparation strategies for MALDI-TOF MS of model
prebiotic reactions in saline solutions.

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