AD	Alzheimer’s disease
Cys	cysteine
CV	coefficient of variation
CVD	cardiovascular disease
DM	diabetes mellitus
EI	electron ionization
FA	formaldehyde
GC	gas chromatography
Hcy	homocysteine
HPLC	high performance liquid chromatography
HTL	homocysteine thiolactone
IBCF	isobutyl chloroformate
LOQ	limit of quantification
MeOH	methanol
MS	mass spectrometry
PB	phosphate buffer
R	correlation coefficient
RT	room temperature
SD	standard deviation
SIM	selected ion monitoring mode
TCA	1,3-thiazinane-4-carboxylic acid
TCA-IBCF	isobutyl derivative of 1,3-thiazinane-4-carboxylic acid
Tris-HCl	tris(hydroxymethyl)aminomethane-hydrochloride acid buffer