Measurement of Sulfated-Glycosaminoglycans

Sulfated-glycosaminoglycan (s-GAG) release from cartilage explants into the culture supernatant was measured at 72 hours after the addition of IL-1α, using the 1,9-dimethylmethylene blue (DMMB) assay.⁴⁵ Where appropriate, s-GAG released into the culture supernatant was calculated by subtracting the s-GAG measured in basal media containing CS at the appropriate concentration. This calculation allowed for the subtraction of s-GAG in the CS added to the basal medium prior to incubation with the cartilage explant. The effect of treatments on the release of s-GAG was expressed as micrograms (µg) GAG per milligram (mg) wet weight of cartilage explant.