This part II study is conducted to quantify the concentration of sterol glycoside (SG) present in the
pump filter residue. The extraction involved an efficient clean-up method to remove fatty acid methyl esters (FAME) followed by quantification of SG using gas chromatography – flame ionization detector (GC-FID). Peak confirmation for sterol glycoside is performed on gas chromatography - mass spectrophotometer (GC-MS). The analytical method is validated based on its calibration linearity, method detection limit (MDL) and sample recovery study.