HPTLC-MALDI TOF MS Imaging Analysis of Phospholipids

Scanning densitometry and mass spectrometry for HPTLC analysis of lipids: The last 10 years

“…The magnitude of the emission can be modulated by the choice of the fluorophore, its concentration and the chromatographic parameters. [11] Lipids do not form adducts with primuline [60] which is compatible with MS for characterization, either in MAL-DI, [61,62] DESI, [56,57] or ESI and APCI through an elution-based HPTLC-MS interface. [12] Reversibility of staining was also mentioned.…”

“…A TLC-plate adapter and software were introduced in 2007 by Bruker Daltonics [61] for directly accomplishing qualitative structural characterization and screening of lipids on the plate. [21,23,51,58,59,62,65,71,75,78,84,117,[126][127][128][129][130][131][132] In a similar way that MS imaging allows the recording of spatially resolved mass spectra from slices of biological tissues, MALDI has also been used to monitor the distribution of selected lipids on the HPTLC plate. For this, peak intensities, in dependence of the position, were converted into gray or a color scale.…”

“…The plates were usually sprayed or dipped with a relatively large amount of organic matrix which is usually overlaid through multiple deposition steps. The most popular matrix was DHB, [58,59,62,71,[74][75][76][77]94,117] which allows detection of virtually all lipids from apolar to polar species, although it is not very sensitive and is a poor matrix for negative ionization. [138] Other employed matrices in HPTLC-MALDI were: 9-aminoacridine [18,19,21,22,42,127] which is the matrix of choice for detecting PE in the negative ionization mode; α-cyano-4-hydroxycinnamic acid CHCA; [51,77] 1,4,6-trihydroxyacetophenone monohydrate (THAP); [77] or glycerol.…”

“…Short-time screening on main PL classes and mapping of individual PL species by MALDI in biological materials were reported. [62] Likewise, PG, PC PE PI, LPE and SM were analyzed in an airborne strain of Pseudomonas fluorescens from air in dust clouds. [75] The resulting profiling of bacterial lipidome showed the unexpected presence of PC.…”