In order to evaluate the effect of chaotropic agents on
proteoglycan and non-collagenous proteins, chicken xiphoid
cartilage was treated with guanidine-HCl and MgCl2 in
different concentrations (1M to 5M), and different periods of
time (12, 24, 48 and 72hr). The maximum yield of uronic acid
was obtained with 3M MgCl2 (73.3%). Concentrations of 4M and
5M of MgCl2 showed that much less uronic acid was removed,
55.3% and 38.1% respectively. Extraction with 3M MgCl2 and 3M
guanidine-HCl resulted better efficiency when performed for 48
hr. Analysis by SDS-PAGE of the extracts obtained with
guanidine-HCl and MgCl2 in different concentrations pointed
out that most components are equally removed with the two
solvents, showing that the extraction with MgCl2 is an
alternative assay to remove non-collagenous proteins from
extracellular matrix.