Table 2.

Strategies for steroid lipid analysis through MALDI MSI.

Study	Cholesterol analysis method	Matrix	Tissue	Instrument
Angelini R. et al.78	Enzyme-assisted derivatization for sterol analysis (EADSA) Conversion of 3β-hydroxy group in cholesterol (m/z 386.3543) to 3 β-oxo using cholesterol oxidase. Charge tagging with Girard-P (GP) hydrazine - cholesterol hydrazone (m/z 518.4105) .	CHCA	Mouse brain	MALDI TOF/TOF (UltraFlextreme, Bruker)
Barre FPY. et al.130	MALDI-2, a positionization strategy, was used to enable a second ionization event to increase the yield of ions. Dehydrated cholesterol (m/z 369.3521 [M + H − H2O]+)	DHB	Human cartilage and dog liver	Orbitrap elite MS coupled to an intermediate pressure MALDI/ESI interface
Dufresne M. et al.131	Silver cationized cholesterol [M+Ag]+ (m/z 493–495))	Matrix free	Mouse brain/kidney	MALDI TOF/TOF (UltraFlextreme, Bruker)
Tobias F. et al.72	Unesterified cholesterol (dehydrated ion, m/z 369.3, [M-H2O+H]+)	DHB	Mouse brain	MALDI TOF/TOF (ScieX)
Patti GJ. et al.132	Silver cationized cholesterol [M+Ag]+ (m/z 493) Nanostructure initiator mass spectrometry (NIMS) combined with Silver nitrate (AgNO3)	Matrix free	Mouse brain	MALDI TOF/TOF (Applied Biosystems)
Cobice DF. et al.133 2023	7-ketocholesterol. Charge tagging with Girard-T (GP) hydrazine precoated on ITO slide.	CHCA	Rat adrenal gland/mouse brain	MALDI-FTICR-MS (Bruker SolariX)
Muller L. et al.134	Silver nanoparticles implantation on tissue [M+Ag3]+. Silver adducts of cholesterol and cholesterol ester [M+Ag]+.	Matrix free	Rat brain	MALDI LTQ-XL-Orbitrap (Thermo Fisher Scientific)
Chaurand P. et al.135	Silver-assisted laser desorption ionization mass spectrometry imaging (AgLDI MSI) for cholesterol quantitation (m/z 493.26) [12CHO+107Ag]+	Matrix free	Mouse brain	MALDI TOF/TOF (UltraFlextreme, Bruker)