Glycosaminoglycans Assay Kit

PRODUCT SPECIFICATIONS

• DESCRIPTION: Assay kit to quantify GAGs
• FORMAT: 96-well ELISA plate with removeable strips
• ASSAY TYPE: Colorimetric assay
• ASSAY TIME: 5 minutes
• STANDARD RANGE: 50 µg/ml to 3.1 µg/ml
• NUMBER OF SAMPLES: Samples NOT containing extra proteins: up to 42 (duplicate) samples/plate Samples containing extra proteins: up to 21 (duplicate) samples/plate
• SAMPLE TYPES: Tissue homogenate
• RECOMMENDED SAMPLE DILUTIONS: Varies
• CHROMOGEN: N/A (read at 525 nm)
• STORAGE: -20°C for 12 months
• VALIDATION DATA: Intra-Assay (1.7-7.6%)/Inter-Assay (5.2-8%)/Spiking Test (106-117%)

INTRODUCTION

Glycosaminoglycans (GAGs) are negatively charged polysaccharides located in most connective tissues and extracellular matrices (ECM), as well as on the surfaces of many cell types. Consisting of repeating core disaccharide units, GAGs are categorized into four types: heparan/heparan sulfate, chondroitin/dermatan sulfate, keratin sulfate, and non-sulfated hyaluronan. Sulfated GAGs in the ECM exist as proteoglycans which typically consist of multiple glycosaminoglycan chains attached to a core protein (1). In a highly organized ECM, articular cartilage is composed of type II collagen, hyaluronan, link protein, and chondroitin sulfate-rich proteoglycans, which provide the osmotic resistance necessary for cartilage to resist compressive loads (2). In addition to type II collagen, GAGs are considered an autoantigen of rheumatoid arthritis (RA), as anti-GAGs antibodies associated with ECM degradation exist in the serum of RA patients (3). Although the role of proteoglycans in RA is still unknown, research shows that immunizing mice with proteoglycans consisting of GAGs can induce arthritis (4). Similarly, the loss of ECM is the first observable change in osteoarthritis (OA), therefore, determining GAGs levels may be a useful marker of disease progression. Furthermore, the successful use of artificial cartilage for the treatment of OA necessitates the analysis of type II collagen and GAGs content to ensure the cartilage quality (5). Chondrex, Inc. provides a sulfated GAGs Assay Kit (Cat # 6022) using cationic dye 1,9 dimethylmethylene blue (DMB) which binds to highly charged sulfated GAGs, not including hyaluronan (6). This kit utilizes an improved DMB solution, minimizing interference with negatively charged contaminants such as DNA and RNA and uses chondroitin sulfate as a standard for the analysis of ECM in cartilage. Moreover, to analyze collagen coexisting with GAGs in cartilage, Chondrex, Inc. provides a variety of type and species-specific collagen detection kits and total collagen detection kits.