Determination of phenolic compounds in insulin preparations includes
extraction with ethyl acetate (phases ratio organic to aqueous is 1:5 with one batch
or 1:10 with two batches) in acidic medium (PH =1.5-2), and then quantification
by GC or UV spectrophotometric techniques. This study leads to ensure that the
preservatives concentrations are effected by different conditions in the store of
insulin preparations. The concentration of methyl paraben was (0.808)mgml after
expiry date by (150-170) days . When the insulin preparations stored at freezing
point for (9-10) days, the concentration of methyl paraben reduced to
(0.37)mgml, and to (0)mgml , after (16-18)days at freezing point . Uv-Vis
method was proposed and applied for drawing calibration curve at 272 nm. for mcresol
which is used as preservative in insulin preparations. While methyl paraben
was determined by GC technique.