Differential Use of Alcian Blue and Toluidine Blue Dyes for the Quantification and Isolation of Anionic Glycoconjugates from Cell Cultures: Application to Proteoglycans and a High-Molecular-Weight Glycoprotein Synthesized by Articular Chondrocytes

Heterogeneous nanostructural and nanoelastic properties of pericellular and interterritorial matrices of chondrocytes by atomic force microscopy

“…The PCM was labeled darker blue relative to both the chondrocyte and the ITM (cf., Fig. 1A), similar to Terry et al (2000). Fig.…”

“…1A), providing a convenient method for separating these microscale structures in situ without enzymatic digestion or mechanical isolation. Toluidine blue has affinity for electronegatives such as those found in proteoglycan-rich connective tissue and nucleic acid rich cell nuclei (Terry et al, 2000), as evidenced in Fig. 1A.…”

“…Under live view in real time, the PCM was characterized and readily identified by a darker ring surrounding individual chondrocytes located in the longitudinal surface of the growth plate sample (cf., Fig. 1A) stained positively to toluidine blue (Terry et al, 2000). Nanoindentation was applied separately in the pericellular matrix (PCM) and interterritorial matrix (ITM) of randomly selected chondrocytes in the lower reserve zone or upper proliferating zone of the growth plate ( Fig.…”

ZHOUPI controls embryonic cuticle formation via a signalling pathway involving the subtilisin protease ABNORMAL LEAF-SHAPE1 and the receptor kinases GASSHO1 and GASSHO2

“…Washing to remove excess external Toluidine Blue has little effect on internalized stain. Internalized stain can, however, be solubilized in 80% ethanol and quantified spectroscopically (Terry et al, 2000). This method proved robust, and allowed us to measure Toluidine Blue uptake relative to cotyledon volume (approximated by Abs 430, an absorbance peak for Chlorophyll A, see supplementary material Fig.…”

Fact versus artifact: Avoiding erroneous estimates of sulfated glycosaminoglycan content using the dimethylmethylene blue colorimetric assay for tissue-engineered constructs

“…The DMMB assay has largely replaced the uronic acid carbazole assay (Bitter and Muir, 1962), which is less sensitive to GAG content and may be inaccurate in the presence of glucose or salts (Frazier et al , 2008; Mort and Roughley, 2007). Assays based on binding of other cationic dyes such as Alcian blue (Whiteman, 1973) or toluidine blue (Terry et al , 2000) see some use, but DMMB has been reported to be more sensitive and reliable (Chandrasekhar et al , 1987; de Jong et al , 1994). GAG analyses via high performance liquid chromatography (Hjerpe et al , 1979) or capillary electrophoresis (Hjerpe et al , 1979) are highly sensitive and specific (Frazier et al , 2008) and can reveal detailed sulfation patterns, but these more specialized methods are not amenable to routine analysis of large numbers of samples.…”